m-2-3 hangers and supports

SOUTHERN COMPANY SERVICES M-2-3 ENGINEERING STANDARDS AND GUIDELINES MECHANICAL PIPE HANGERS AND SUPPORTS

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Pipe Hangers and Supports

Index

1.0 INTRODUCTION

1.1. Purpose 1.2. Scope

2.0 DEFINITIONS 3.0 CODES AND STANDARDS 4.0 DESIGN CRITERIA AND GUIDELINES

4.1. Component Designation 4.2. Loads 4.3. Pipe Stress 4.4. Welds 4.5. Support Spacing 4.6. The Pipe Support Contractor and Support Details 4.7. Pipe Support Callout 4.8. Specialty Supports 4.9. Support Placement Tolerance

5.0 PIPE SUPPORT TYPES AND COMPONENTS – RIGID SUPPORTS

5.1. Rod Hangers and Components 5.1.1 Beam Attachments 5.1.2 Hanger Rods 5.1.3 Turnbuckles 5.1.4 Clamps 5.1.5 Welds 5.1.6 Trapeze Hangers


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5.1.7 Riser Clamps 5.1.8 Washer Plates

5.2. Pipe Shoe and Stanchion Supports 5.3. Guides 5.4. Limit Stops 5.5. Anchors 5.6. Welded Pipe Attachments

6.0 PIPE SUPPORT TYPES AND COMPONENTS – ENGINEERED SUPPORTS

6.1. Variable Spring Hangers 6.2. Constant Supports 6.3. Design of Supplemental Steel

7.0 REFERENCES

Appendices

Appendix A Standard Support Details Appendix B Supplemental Steel Appendix C FRP Standard Support Details Appendix D HDPE Standard Support Details Appendix E Pipe Support Guidelines; FRP & HDPE Pipe


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REVISION PAGE 1.0 REVISION 1 1.1 Index:

Added sub section 4.9 in section 4.0 Added Appendix C: FRP Standard Support Details Added Appendix D: HDPE Standard Support Details Added Appendix E: Pipe Support Guidelines; FRP and HDPE Pipe in section 7.0

1.2 Appendix A:

Added Rigid Base Support details RBS-10 through RBS-16 in section 2.0 Added Rod Hanger detail RHS-5 in section 3.0 Added Guide Base Support details GBS-12, GBS-13 and GBS-14 in section 4.0 Added Anchor Base Support details ABS-7, ABS-8 and ABS-9 in section 6.0

1.3 Appendix B:

Added detail 1D in section 2.0 Added detail 5G in section 6.0 Added details 7F, 7G, 7H, 7J, 7K and 7L in section 8.0 Added details 8H and 8J in section 9.0 Added detail 11B in section 12.0 Added detail 12B in section 13.0

1.4 Added Appendix C: FRP Standard Support Details 1.5 Added Appendix D: HDPE Standard Support Details 1.6 Added Appendix E: Pipe Support Guidelines; FRP & HDPE Pipe


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PIPE HANGERS AND SUPPORTS 1.0 INTRODUCTION 1.1 Purpose

This document provides a guideline for the design of pipe supports. The document is not intended to supersede project specific design criteria but to reflect current SCS practices.

1.2 Scope

This standard shall apply to pipe supports for piping systems ranging in size up to 24 inches, unless noted otherwise.

For the purposes of this standard, pipe supports have been divided into two main categories: • Rigid Pipe Supports – Application where rigid pipe hangers are acceptable.

Design Engineering shall be responsible for the location and selection of rigid pipe hangers. Generally, after the engineer has identified the type and location of rigid supports, the detailer shall use the guidelines in section 5.0, Pipe Support Types and Components – Rigid Supports, to provide detailed support design.

• Engineered Supports – Application where support flexibility must be designed into

the piping system by providing variable springs, constant supports and/or rigid hangers, or the support design is critical to the system.

Design Engineering shall be responsible for the design of engineered pipe hangers and supports. Design criteria and guidelines are given in section 6.0 of this standard. Engineered supports shall be specified after a thorough pipe stress analysis has been performed, unless noted otherwise. See Mechanical Standard M-2-2, Piping Stress Analysis.

NOTE

Piping systems containing engineered supports shall be designed as an engineered system of supports. Therefore, the engineer and detailer shall refer to section 5.0, Pipe Support Types and Components – Rigid Supports, of this standard, when rigid type supports are required as part of the engineered pipe support system.

2.0 DEFINITIONS

The following definitions are applicable to new generation, environmental, and retrofit projects.

2.1 Piping System Category – Indicates the piping system’s criticalness of service as defined

in Pipe Class Criteria found in appendix A of Piping Design Standard M-2-1. In general, there are the following three categories:


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2.1.1 Category 1/Critical Systems - These systems include main steam, hot and cold reheat, boiler feed-water pump suction, and discharge. The failure of any of these systems will result in the loss of generation capability and/or substantially impact the safety of plant personnel.

2.1.2 Category 2/Intermediate Systems - These systems include extraction steam, high pressure heater drains, or condensate systems. Failure of any of these systems has less impact on the loss of generation capability or personnel safety.

2.1.3 Category 3/Non-critical Systems - All other systems such as floor drains, cold water

systems, potable water, plant service water, vents, or circulating water. Failure of any of these systems has no impact on generation capability.

2.2 Design Load - This is the pipe load used in the design of the pipe support. It is the higher

of the load cases for the piping system.

2.3 Operating Load - This is the pipe load that acts on the support when the system is in service. This load is the algebraic sum of weight load and thermal load. Operating load is equal to hot load for spring hangers.

2.4 Hydrostatic Load - This is the pipe load acting on the support during hydrostatic testing of the piping system. Hydrostatic loads are often much higher than design loads for steam and gas piping systems.

2.5 Sustained Load - This is the sum of the weight of the pipe, contents, and pipe support attachment components plus the pressure acting on the system.


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2.6 Minimum Load - The support shall be designed for the minimum load if the design load is less than the minimum load. The table below (reprinted from MSS SP-58 Pipe Hangers and Supports – Materials and Fitting Industry) suggests the minimum design loads based upon the pipe size. This minimum load should be used in designing supplemental steel.

MINIMUM DESIGN LOADS

(From MSS SP-58 Pipe Hangers and Supports – Materials and Fitting Industry)

Nominal Pipe Size (in) Load (lb) 3/8 150 ½ 150 ¾ 150 1 150 1 ¼ 150 1 ½ 150 2 150 2 ½ 150 3 200 3 ½ 210 4 250 5 360 6 480 8 760 10 1120 12 1480 14 1710 16 2130 18 2580 20 3060 24 3060

2.7 Thermal Load - Stresses imposed on the piping system due to expansion or contraction

(or both) of the components due to a wide range of temperatures. 3.0 CODES AND STANDARDS

Pipe support design is governed by the codes and standards that apply to the piping system. The piping codes used in new generation, environmental, and retrofit projects have provisions for the design of pipe supports. The designer should be familiar with the support design portions of the applicable codes listed in section 7.0 References.


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4.0 DESIGN CRITERIA AND GUIDELINES 4.1 Component Designation

For the purpose of design standardization all support component designations shall be based on the Anvil International, Inc. Pipe Hangers Catalog numbering system.

4.2 Loads Supports shall be designed for the most severe conditions of coincident pressure, weight, temperature, and any fluid dynamic events. In addition, piping exposed to wind load, snow, ice, earthquake, or other natural phenomena shall be designed for such loading.

4.3 Pipe Stress

Critical piping systems, Piping Category 1, 2, or otherwise designated due to piping loads, shall be stress analyzed in accordance with Mechanical Standard M-2-2, Piping Stress Analysis. The pipe support engineer and designer shall base pipe support selection and design on results from the pipe stress analysis.

4.4 Welds Welding or bolting attachments to the building or pipe rack structural steel shall be done in accordance with the latest edition of the AISC Manual of Steel Construction – Allowable Stress Design. Maximum allowable shear stress in welds shall be limited to 80 percent of the maximum allowable stress of the weaker of the base metals being joined. Maximum allowable tension and bending stresses in welds shall be limited to the maximum allowable stress of the weaker of the base metals being joined.

4.5 Support Spacing Horizontal piping shall be supported such that excessive sag, bending, or shear stress is minimized. Special consideration will be given where components such as flanges and valves impose concentrated loads. Vertical piping shall be supported with riser clamps. See section 5.1.7 Riser Clamps for spacing of vertical restraints. Supports for piping 3 inches or larger shall be designed and detailed individually. Supports for piping 2 1/2 inches and smaller shall be designated as field-designed and located (except for Category 1 and 2 systems), unless noted otherwise. Field-designed pipe supports shall consider all critical movement, load, and operational conditions. Design criteria and guidelines for rigid-type pipe hangers given in section 5.0 Pipe Support Types and Components – Rigid Supports shall be followed. Where stress analysis calculations are not performed, pipe support spacing for standard and heavier weight pipe shall be in accordance with table 121.5 of ASME B31.1 code. Suggested pipe support spacing chart is reprinted in table 4.5. This chart shall not be used where components, such as flanges and valves, impose concentrated loads.


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Table 4.5 SUGGESTED PIPE SUPPORT SPACING

Suggested Maximum Span (carbon steel pipe only)

Nominal Pipe Size (NPS) Water Service (ft) Steam, Gas, or Air Service (ft)

1 7 9 2 10 13 3 12 15 4 14 17 6 17 21 8 19 24 12 23 30 16 27 35 20 30 39 24 32 42

NOTES:

1. The above data is based on ANSI B31.1 – Power Piping Code. 2. The maximum spacing for pipe supports, shown above, applies only for horizontal straight runs of standard

weight and heavier pipe when the operating temperature does not exceed 750˚ F. 3. The above table does not apply where span calculations are made or where there are concentrated loads

between supports such as flanges, valves, and specialties. 4. The spacing shown above is based on a maximum combined bending and shear stress of 2800 psi and

insulated pipe filled with water or the equivalent weight of pipe or steam, gas or air service. The pitch of the line is such that sag of 0.1 inch between supports is permissible.

4.6 The Pipe Support Contractor and Support Details

Manufacturers Standardization Society specification MSS SP-77 Guidelines for Pipe Support Contractual Relationships shall be used as the basis for establishing responsibilities for pipe support details. Contractual relationships shall be arranged to track the following in order of governing precedence: 1. Project specific contract documents 2. This standard M-2-3 Pipe Hangers and Supports 3. MSS SP-77 Guidelines for Pipe Support Contractual Relationships

Pipe support details shall be developed with information provided by Design Engineering drawings and stress analysis results, if applicable. Pipe support details shall be developed by an SCS-approved pipe support contractor. The contractor shall be responsible for pipe support details, development of the bill of materials, fabrication, and delivery of pipe support assemblies. As dictated by the project and where job requirements permit, Design Engineering may develop pipe support details, or typical details may be used in lieu of individual drawings. The following information is required by the pipe support contractor and provided by Design Engineering:


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• Location of pipe support assembly with respect to the piping system along with the support type and supplementary steel type, if required, shall be shown on the piping isometric and/or orthographic drawings. Support load required for the contractor to size supplementary steel. In some instances, support steel size may be shown in lieu of load.

• Detailed structural steel and concrete drawings. • For spring hangers, hot and cold loads, hot and cold positions, and hydro load shall be

noted. • For constant supports, design load, calculated travel (up or down), and total travel

shall be noted. The pipe support contractor shall provide the following: • Complete pipe support assembly drawings including details of supplemental steel,

when applicable. When loads are submitted in lieu of steel size, the contractor is responsible for sizing the appropriate steel. Consideration must be given to appropriate bearing surface as well as load capacity. Design, fabrication and erection of structural steel shall be in accordance with the AISC manual of steel construction, latest edition.

• Complete bill of materials. • Weld sizes. Special field welding procedures shall be noted when required. • Supply of pipe support assemblies.

All documents provided by the pipe support contractor shall contain the plant, unit, line number, and pipe support callout matching the purchaser’s documents. The pipe support contractor’s design documents are subject to review and approval by Design Engineering prior to release for fabrication. Existing support steel shall be utilized, when possible. Complex supplemental steel arrangements should be avoided if possible.

4.7 Pipe Support Callout

Pipe supports shall be tagged on the piping isometric and/or orthographic drawings. Each pipe support shall have an identification number, Sx, where x identifies the bill of materials item number. Each pipe support shall have a pipe support detail callout which shall contain the support type (Appendix A), a unique identifier, and supplemental steel type (Appendix B). A short description shall be included in the bill of materials along with the calculated load, if applicable. The pipe support identifier shall be unique for a particular line number.


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Both tags shall have a box surrounding the number. Example: S9

GBS-5-01/1A

S9 - bill of materials item number GBS-5 - pipe support type 01 - unique pipe support identifier 1A - supplemental steel type

When specifying that existing structural steel will be used and supplemental steel will not be necessary, no designation will follow the pipe support unique identifier (for example GBS-5-01).

4.8 Special Supports

When necessary, project-specific supports shall be noted in the following manner: S10

SP-02/1A

S10 - bill of materials item number SP - support type (SP denotes special or project-specific) 02 - unique pipe support identifier 1A - supplemental steel type

4.9 Support Placement Tolerance Support installation location shall be within ± 1’-0” from that designated on the pipe support drawing, piping isometric, or orthographic. 5.0 PIPE SUPPORT TYPES AND COMPONENTS – RIGID SUPPORTS 5.1 Rod Hangers and Components

The rod hanger is the most common type of hanger in a piping system. The rod hanger is a rigid, one-way vertical restraint consisting of a rod attached to a pipe clamp at one end and to the building or pipe rack structure at the other end, usually via a beam attachment. Rod hangers should not swing more than 4 degrees from the vertical position. Where necessary, offset of pipe attachments and building/rack attachments shall be used to maintain the 4-degree angular swing and to maintain concentric loading of the hanger when the piping is at operating conditions.


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5.1.1 Beam Attachments

Welded beam attachments with a pin or bolt shall be used where possible. This type of attachment can accommodate a welded eye rod or weld-less eye nut and allows up to a 4-degree swing of the rod in the direction parallel to the pin. Mechanical beam attachments or beam clamps shall be used for ambient systems (temperature < 120ºF) or for temporary support. Their use is prohibited except for dry pipe fire protection sprinkler systems, draft system sensing lines, or other light duty piping systems.

A welded beam lug and clevis shall be used when the beam flange is not wide enough to accommodate the welded beam attachment. The beam lug shall be used for pipe supports requiring double lugs.

Load pins shall have cotters to prevent slippage. Load bolts shall have jamming nuts (double nut). All bolted joints shall have locking devices, such as jam nuts. Offsetting thread or tack-welding shall not be used, unless stated otherwise.

For a welded beam attachment, the welding shall be performed on the straight sides of the attachment only. There shall not be any welding on beam attachment rounded sides or across the webs of beams. When attachment to concrete is required, embedded anchor bolts or inserts shall be utilized. Approved concrete fasteners shall be used in shear only where required.

5.1.2 Hanger Rods

Machine threaded rods or welded eye rods shall be used unless stated otherwise. Linked eye rods shall be used to accommodate large lateral and axial movements of pipe. Standard load rated hanger rods shall be used. Table 121.7.2(A) of B31.1 code provides load carrying capacities for threaded rods made of A-36, A-575, and A-576 hot-rolled carbon steel. To support hot and insulated piping, hanger rods shall be fitted with a forged or welded eye connected to the pipe clamps through a load pin or load bolt separate from those bolts attaching the clamp to the pipe. Hanger rods should not be subjected to bending or stresses other than tension. Where lateral or axial movement is anticipated, suitable linkages shall be provided to permit swinging. Hanger rods shall not be threaded directly to concrete fasteners. Attachment by conventional means to an intermediate plate or member held in place by at least two full-strength concrete fasteners is required.

5.1.3 Turnbuckles

Turnbuckles shall be used to provide an adjustable length connection between two rods. Orient the turnbuckle with the left-hand thread at the top and the right-hand thread at the bottom. This will shorten both rods when the turnbuckle is turned counterclockwise and lengthen both rods when the turnbuckle is turned clockwise.


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For rod take-out calculations (specifying length of rods to be purchased), a 3-inch gap between rod tips within the turnbuckle shall be used for a standard 6-inch turnbuckle. The turnbuckle is typically located about 3 feet from the pipe for ease of adjustment. A right-hand threaded hex nut with lock nut shall be used for jamming the turnbuckle to prevent it from disengaging.

5.1.4 Clamps

Two-bolt pipe clamps shall be used to support cold pipelines with little or no insulation. Three-bolt clamps shall be used for all other systems. For high temperature piping systems (temperature > 750 ºF), alloy clamps shall be used. Otherwise, carbon steel clamps are adequate. Jamb nuts (or suitable locking devices) shall be specified for clamp bolts.

5.1.5 Welds

Beam attachments should be welded to building, pipe rack, or supplemental steel with fillet welds along two edges of the attachment. Unless pipe movement otherwise dictates, orient the attachment so that the axis of the pin or bolt is parallel to the axis of the beam. The weld should run along the beam flange. Welding shall be on the straight sides of the attachment, not on the rounded sides. Welds shall be designed to develop the full strength of the pipe support component being joined.

5.1.6 Trapeze Hangers

Trapeze hangers shall be used to avoid interferences, especially where a piping system is routed below another piping system. Pipe may be off center of the trapeze. Where piping is off-center, spring hanger spring loads must be re-calculated. Pipe must be attached to a trapeze by an anchoring device such as a U-bolt. When required, insulation protection devices shall be used with trapeze hangers when the pipe is insulated. Rods used in trapeze hanger assemblies shall be designed to carry a minimum of 75 percent of the calculated total operating load.

5.1.7 Riser Clamps

Riser clamps shall used to support vertical piping. Friction shall not be relied upon to hold the riser clamp in place. A minimum of three shear lugs shall be provided and welded to the pipe along the two vertical sides and the top with sufficient weld material to support the total pipe load. Shear lugs shall be manufactured of the same material as the pipe. Typically, a pipe support vendor has three types of riser clamps:

• Simple strap with four bolts. • Heavy duty type. • Welded, reinforced bars (to take torsion out of the clamp and increase the capacity).

When designing supports with riser clamps, consideration shall be given to the load pin center-to-center dimensions. The center-to-center span should be kept as close to the pipe as possible to reduce the bending effect on the clamp.


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Each rod of a riser support shall be sized for the full load of the support. This requirement does not apply to spring or constant supports where the rod size is determined by the spring housing itself. Where vertical restraints are required on piping systems (such as main steam, hot reheat, cold reheat, extraction to deaerator, and boiler feed pump suction piping), each support rod must be capable of supporting 60 percent of the total hydrostatic load of the riser and adjacent piping or 75 percent of the calculated operating load - whichever is greater. This requirement is necessary although other hangers may be designed to support the riser. Generally, the support spacing shall be limited to 1.5 times the recommended horizontal spans, and the vertical restraint must be located above the center of gravity of the riser. The vertical restraint shall be located in the upper third of the pipe. Alloy risers and pipe clamps shall use bolting material manufactured from ASTM A-193, B-7 studs, and A-194 grade 2H heavy hex nuts, unless required otherwise.

5.1.8 Washer Plates

When pairs of channels are used as supplemental steel, a washer plate shall be welded to both the top and bottom flanges of the channels to prevent rotation of the channel. The washer plate shall be selected to match the rod size. The hole in the washer plate should be 1/8 inch larger in diameter than the rod, unless required otherwise. The hanger rod extends through the channels and shall be attached using two hex nuts.

5.2 Shoe and Stanchion Supports

Shoe and stanchion supports are rigid, one-way vertical restraints. Piping without insulation shall be supported from below by resting it on a steel member or by welding a pipe stanchion and a plate. Piping with insulation shall be supported from below by welding a shoe, a pipe covering protection saddle, or a pipe stanchion and a plate. Welded attachments to pipe shall be designed for the vertical force to be supported at the given support location. A pipe shoe, pipe covering protection saddle, or pipe stanchion and a plate shall be supported on a sliding surface of a steel member or a steel plate anchored on a concrete member.

5.3 Guides

Guides are two-way piping system restraints. In horizontal piping, the pipe shall be supported vertically and restrained in lateral direction. In vertical risers, the pipe shall be restrained in the lateral direction only. Two common types of guides are the box type and sway strut type. The box-type guide, built up by using structural steel members, shall be used for low-temperature piping systems, unless required otherwise. Box-type guides should not be used for high-temperature systems because of pipe contact with structural members. Such contact results in friction caused by axial movement of the pipe and heating of the structural member. High-temperature systems also have significant insulation which requires additional components such as insulation shoes or lugs.


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Two perpendicular sway struts can provide the same movement control as a box guide. This type of arrangement has advantages over the box type: • Simpler to design and install. • Flexible in orientation. • Require less space. • Provide more pipe axial movement without friction load. • Allow field adjustment.

Sway strut guides require standard support components that need considerable lead time from order to delivery. The use of sway struts may not be economical for supporting light loads or small-bore pipe, especially cold pipe. The following cautions apply to the design of guides using sway strut assemblies: • When a sway strut is used in the vertical direction, the piping shall be supported from

above rather than from below. • The pin-to-pin dimension for allowable load shall be verified. The longer a strut, the

lower its buckling load. • The angle between the two struts should be no less than 45 degrees and no more than

135 degrees. Where this condition cannot be satisfied, the piping model and stress analysis shall be modified accordingly.

5.4 Limit Stops

Limit stops are two-way restraints in a piping system. In horizontal piping, the pipe shall be supported vertically and restrained in order to control axial movements. Limit stops are most often found in high temperature and insulated piping systems. Limit stops shall be built by welding two plates or shoes axially to a pipe, 180 degrees apart. Axial pipe movement is restrained by attaching a steel member across the plate or the shoe. The limit stop plate or shoe and steel members shall be designed to resist the limit stop restraint loads determined by a stress analysis load report.

5.5 Anchors

Anchors shall be designed to restrain the movement of pipe in all directions. Anchors are built by welding plates, shoes, or stanchions around pipe. Such an anchor assembly shall be welded or bolted to the building or pipe rack structure. The weld and the size of the plates, shoes, or stanchions welded to the pipe shall be designed for the anchor design loads determined by a stress analysis load report. As necessary, anchor, guide, and limit stop restraint loads shall be reviewed by the civil or structural design group before issuing the final design.


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5.6 Welded Pipe Attachments

Welded pipe attachments include shear lugs, stanchions, insulation lugs, and other assemblies which transfer the load from the pipe to the support. Welded attachment lugs impose local stress on the pipe wall which must be considered. The design of shear lugs on a pipe riser’s vertical restraints shall be such that only half of the number of lugs shall be required to carry the total load of the support. For example, if the total load is 4,000 lb and the support has 4 lugs, each lug shall be designed to carry a load of 2,000 lb. This provision anticipates that fabrication tolerance, erection, pipe movements, or other factors prevent the contact of all the lugs onto the clamp or supporting structure.

For pipe larger than 6 inches NPS, at least four lugs shall be used for axial support in each direction. Lugs shall be welded on two sides and on the top. Lug material shall be the same as the piping material. Stanchions may be welded to the pipe. Welds between the stanchion and the pipe should be partial penetration welds with a fillet cap. The weld shall be treated as a piping weld.

6.0 PIPE SUPPORT TYPES AND COMPONENTS – ENGINEERED SUPPORTS

6.1 Variable Spring Hangers

Spring hangers, or variable supports, allow pipe to move vertically while still providing support. This support varies according to the amount of pipe movement.

Spring hangers shall be supported in such a manner that the rod will remain concentric with the spring at all times and will not be subject to bending. Rollers or similar approved supports shall be provided in the event the amount of hanger rod angular swing exceeds 4 degrees. Spring hangers or variable supports consist of pre-compressed enclosed springs. A load plate positioned on top of the spring is attached to the pipe so the pipe weight compresses the spring. The spring housing transfers the support load to the building or pipe rack structure. There are seven types of variable spring hangers to choose from depending on the way the spring is attached to the building/pipe rack structure or pipe. Refer to Anvil International Pipe Support Catalog for additional descriptions and pictures of each hanger type. Type A spring hangers are used where sufficient headroom is available. The spring cans should be furnished with threaded connections and rod stops in the top plate to provide a simple attachment for the upper rod connection. Adjustment and spring loading are accomplished by turning the load coupling or turnbuckle to achieve the desired spring load or pipe elevation.


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The supports for type A spring hangers should be designed with the spring can positioned approximately 3 to 5 feet from the pipe to provide access for inspection. A turnbuckle shall be installed between the pipe clamp and the spring can for load adjustment, unless noted otherwise. Type B and type C spring hangers are used where headroom is limited, and the spring cans have to be attached directly to the building or pipe rack structure. Type B spring hangers have a single lug welded to the top plate of the housing. Type C spring hangers are similar to type B hangers, but instead of a single lug, type C spring hangers have double lugs welded to the top plate of the housing. Unless the beam attachment requires otherwise, type B spring hangers shall be used. Type D and type E spring hangers are used to position the spring can above the support structure (usually a pair of channels). Type D spring hangers are adjusted using the load nut on top of the spring housing. Instead of a top-mounted load nut, type E spring hangers are usually supplied with a turnbuckle and adjusted from below. Type F spring hangers are designed to support piping from below. The disadvantage of this type is its unsatisfactory performance when subjected to significant lateral pipe movement. Pipe movement may cause the load plate to tilt, or the pipe may move off the load plate. Hanger manufacturers recommend rollers for pipe with high axial movements. Type G spring hangers are made up of two spring units welded to the ends of a single angle or pair of channels in a trapeze configuration. This type of support is used where headroom is limited or where obstruction prohibits the use of a single spring hanger. When specifying this type of spring hanger, it is assumed that the pipe is centered between the springs, each spring carrying only half the total pipe load. Most variable supports shall have no more than 25 percent variability. Variable supports in critical systems such as main steam, hot reheat, or cold reheat shall have less than 10 percent variability. Constant supports should be used if the above variability cannot be met. Where designing spring pipe supports for piping systems subject to vibration, the spring unit shall be attached directly to the building or pipe rack structure. If the spring can is positioned in the middle of a long rod, piping vibration will cause the spring can to eventually bend the rod. The disadvantage of attaching the spring can to the building/pipe rack structure is the difficulty of spring adjustment or inspection. The spring can should be positioned as close as possible to the pipe and never at the middle of a long rod. The weight of the spring unit must be added to the specified load in setting the hot and cold loads of the spring. The weight of the components, especially the clamp weight, acting on the spring may be significant. Because the pipe load is acting on the housing of the spring, and the load plate is attached to the building or pipe rack structure, the weight of all components shall be taken into account if the hot or cold load settings are near the bottom of the spring hanger’s operating range.

Variable springs shall be equipped with a complete travel stop for steam and liquid fluid piping systems. Travel stops for hot air or flue gas systems shall be equipped with cold


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travel stops. Load scales shall be equipped with permanently attached cold and hot buttons. Stops should be removed after hydro test only.

6.2 Constant Supports A constant support is a spring hanger with a mechanism located inside the spring housing. The mechanism allows a balance of spring force and the pipe weight in such a way that the supporting load remains constant throughout the range of pipe travel. In a critical piping system such as main steam, hot reheat, or cold reheat, the thermal expansion of the piping system may reach 6 to 12 inches, but the allowable range is 6 percent. Constant supports shall be used when the load variability of a spring hanger is not acceptable. Constant supports can generally be divided into two categories: vertical and horizontal. Constant support designs vary from one manufacturer to another. Hanger catalogs should be used in choosing constant supports. Constant pipe supports shall be designed for a 2-inch difference between the calculated thermal movement and the total travel for pipe movements less than 4 inches. When predicted pipe movements will exceed 4 inches, the support is designed for a 50 percent difference between actual and total travel. For example, if the pipe moves 6 inches, the calculated travel shall be 6 inches, and the total specified travel shall be 9 inches. The constant support should have at least 9 inch total travel. In designing a constant support hanger, all component weights acting on the support spring must be taken into account. The load adjustment of a constant support is much more limited than that of a spring hanger. As with type G spring hangers, the weight of type G constant supports must be added to the total load acting on the support.

Constant pipe supports shall be equipped with a permanent travel stop with load

indication.

6.3 Design of Supplemental Steel

Building steel and pipe rack steel shall be used for support where practical. Support spans shall be governed by paragraph 121.5 of ANSI/ASME B31.1 Power Piping Code with due consideration of concentrated loading caused by valves, flanges, and other fittings. See table 4.5 for suggested pipe support spacing. Supplemental steel shall be designed and provided when building or pipe rack steel necessary to conform to support requirements cannot be located. Supplemental steel shall be designed for the larger of the pipe design loads and the hydrostatic test load. Supplemental steel shall be designed in accordance with the requirements of the AISC Manual of Steel Construction.

Support structures shall be designed with proper stiffness to prevent excessive support deflection that could invalidate the piping stress analysis. For critical systems, a rigid


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support should not deflect more than 1/16 inch. For non-critical systems, a deflection of 1/8 inch is allowed. Where it is necessary to frame structural members between existing steel or concrete members, such supplemental steel shall be designed in accordance with American Institute of Steel Construction Specifications, the Uniform Building Code, or similar recognized structural design standards. Concrete connections shall be made only when addition of supplemental steel is impractical. Base plate shall be anchored to the concrete, except in cases of pure tension loading. Expansion bolts shall be wedge-type, Hilti, Kwik bolts, or equal. Use maximum embedment length recommended by manufacturer. Concrete beam attachments shall be bolted through or welded to cast-in place insert plates. Pipe supports shall not be attached to concrete block walls.

7.0 REFERENCES

American Institute of Steel Construction (AISC). AISC Manual of Steel Construction American Society of Mechanical Engineers.

ASME B31.1 – Power Piping ASME B31.3 – Process Piping ASME Boiler and Pressure Vessel Code

American Society of Testing and Materials American Welding Society. AWS D1.1 Structural Welding Code – Steel Anvil International, Inc. Pipe Hangers Catalog Manufacturer’s Standardization Society of the Valve and Fitting Industry.

MSS SP-58 Pipe Hangers and Supports – Materials and Fitting Industry MSS SP-69 Pipe Hangers and Supports – Selection and Application MSS SP-77 Guidelines for Pipe Support Contractual Arrangements MSS SP-89 Pipe Hangers and Supports – Fabrication and Installation Practices MSS SP-127 Bracing for Piping Systems Seismic-Wind-Dynamic Design, Selection, Application

SOUTHERN COMPANY SERVICES M-2-3 ENGINEERING STANDARDS AND GUIDELINES APPENDIX A MECHANICAL PIPE HANGERS AND SUPPORTS

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Appendix A: Standard Support Details

Index

1.0 GENERAL NOTES 2.0 RIGID BASE SUPPORT

2.1 RBS-1: Pipe On Steel 2.2 RBS-2: Adjustable Pipe Stanchion Support 2.3 RBS-3: Non-Adjustable Pipe Stanchion Support 2.4 RBS-4: Pipe Clamp and Stanchion Support 2.5 RBS-5: Pipe Covering Protection Saddle 2.6 RBS-6: Pipe Shoe, 8” and Smaller 2.7 RBS-7: Pipe Shoe, 10” and Larger 2.8 RBS-8: Pipe Slide Bearing 2.9 RBS-9: Dummy Leg Supports 2.10 RBS-10: U-Bolt Support 2.11 RBS-11: Insulation Shield Support 2.12 RBS-12: Insulation Shield U-Bolt Support 2.13 RBS-13: Riser Clamp Support 2.14 RBS-14: Riser Trunion Support 2.15 RBS-15: Thin Wall Pipe Rigid Support, 2”-12” 2.16 RBS-16: Thin Wall Pipe Rigid Support, 14”-48”

3.0 RIGID HANGER SUPPORT

3.1 RHS-1: Pipe Clevis – Rod Hanger 3.2 RHS-2: Double Bolt Pipe Clamp – Rod Hanger 3.3 RHS-2A: Alloy Double Bolt Pipe Clamp – Rod Hanger 3.4 RHS-3: Riser Clamp – Rod Hanger 3.5 RHS-4: Trapeze – Rod Hanger 3.6 RHS-5: Thin Wall Pipe Rod Hanger

4.0 GUIDE BASE SUPPORT

4.1 GBS-1: Guide – U-Bolt 4.2 GBS-2: Guide – Adjustable Pipe Stanchion and U-Bolt 4.3 GBS-3: Guide – Pipe Covering Protection Saddle and U-Bolt 4.4 GBS-4: Guide – Stanchion and Plate 4.5 GBS-5: Guide – Pipe Shoe, 8” and Smaller 4.6 GBS-6: Guide – Pipe Shoe, 10” and Larger 4.7 GBS-7: Guide – Pipe Covering Protection Saddle 4.8 GBS-8: Riser Guide – Pipe Saddle and U-Bolt


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4.9 GBS-9: Riser Guide – With Stanchion 4.10 GBS-10: U-Bolt Supports – For Light Loads 4.11 GBS-11: Pipe Slide Bearing Guide 4.12 GBS-12: Insulation Shield Support Guide 4.13 GBS-13: Thin Wall Pipe Guide Support, 2”-12” 4.14 GBS-14: Thin Wall Pipe Guide Support, 14”-48”

5.0 LIMIT BASE SUPPORT

5.1 LBS-1: Limit Stop – Saddle and Tees 5.2 LBS-2: Limit Stop – Pipe Shoe, 8” and Smaller 5.3 LBS-3: Pipe Shoe, 10” and Larger

6.0 ANCHORED BASE SUPPORT

6.1 ABS-1: Anchor – Horizontal Pipe (Concrete) 6.2 ABS-2: Anchor – Horizontal Pipe (Steel) 6.3 ABS-3: Anchor – Pipe Riser 6.4 ABS-4: Anchor – Pipe Shoe, 8” and Smaller 6.5 ABS-5: Anchor – Pipe Shoe, 10” and Larger 6.6 ABS-6: Non-Adjustable Pipe Stanchion Anchor 6.7 ABS-7: Thin Wall Pipe Anchor Support, 2”-12” 6.8 ABS-8: Thin Wall Pipe Anchor Support, 14”-48” 6.9 ABS-9: Pipe Anchor Support, 1”-24”

7.0 SPRING HANGER SUPPORT

7.1 SHS-1: Variable Spring – Type “B” Spring 7.2 SHS-2: Variable Spring – Type “C” Spring 7.3 SHS-3: Variable Spring – Type “D” and Type “E” Spring 7.4 SHS-4: Variable Spring – Type “F” Spring 7.5 SHS-5: Variable Spring – Type “G” Spring 7.6 SHS-6: Variable Spring – Trapeze 7.7 SHS-7: Variable Spring – On Riser

8.0 CONSTANT HANGER SUPPORT

8.1 CHS-1: Constant Spring – Type “B” Support 8.2 CHS-2: Constant Spring – Type “C” Support 8.3 CHS-3: Constant Spring – Type “D” Support 8.4 CHS-4: Constant Spring – Type “E” Support 8.5 CHS-5: Constant Spring – Type “G” Support

9.0 DETAILS

9.1 Detail-1: Base Plate Detail – Pipe Stanchion


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9.2 Detail-2: Anchored Base Plate Detail – Pipe Stanchion 9.3 Detail-3: Upper Rod Hanger Assembly 9.4 Detail-4: Shoe Table and Notes


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1.0 General Notes


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2.0 Rigid Base Support


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SOUTHERN COMPANY SERVICES M-2-3 ENGINEERING STANDARDS AND GUIDELINES APPENDIX B MECHANICAL SUPPLEMENTAL STEEL

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Appendix B: Supplemental Steel

Index

1.0 DESIGN RULES FOR SUPPLEMENTAL STEEL

2.0 BEAM TO BEAM

2.1 1A: Span Between Beams 2.2 1B: Span Under Beam 2.3 1C: Span Underside Beams With Overhang 2.4 1D: Span Over the Beams

3.0 BETWEEN COLUMNS

3.1 2A: Steel to Steel 3.2 2B: Concrete to Steel

4.0 COLUMN TO COLUMN

4.1 3A: Side of Column/Under Beam 4.2 3B: Side of Column/Above Beam 4.3 3C: Side of Column/Under Beam with Extension

5.0 FLOOR BRACED MEMBER

5.1 4A: Floor Braced Tier

6.0 EXTENDED MEMBER

6.1 5A: Horizontal Cantilever 6.2 5B: Vertical Cantilever 6.3 5C: From Side of Beam 6.4 5D: Cantilever From Underside of Beam 6.5 5E: Vertical Cantilever Angle 6.6 5F: Straddle Underside of One Beam 6.7 5G: From Side of Column

7.0 CANTILEVER

7.1 6A: Cantilever Underside Unequal Beams 7.2 6B: Cantilever Underside Equal Beams 7.3 6C: Modified Structural Trapeze

8.0 KNEE BRACES

8.1 7A: Knee Brace From Column 8.2 7B: Knee Brace Tier From Column 8.3 7C: Cantilever From Column 8.4 7D: Cantilever From Concrete Wall 8.5 7E: Bolted Cantilever From Column 8.6 7F: Cantilever Angle Frame From Vessel


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8.7 7G: Riser Support Frame From Vessel 8.8 7H: Riser Guide Frame From Vessel 8.9 7J: Sway Brace For Riser 8.10 7K: Riser Guide Frame Off Beam 8.11 7L: Riser Guide Frame Off Column

9.0 TRAPEZES

9.1 8A: Single Tier Structural Trapeze 9.2 8B: Double Tier Structural Trapeze 9.3 8C: Triple Tier Structural Trapeze 9.4 8D: Structural Trapeze Equal Legs 9.5 8E: Structural Trapeze Unequal Legs 9.6 8F: Under Beam-Angle Frame 9.7 8G: Trapeze With Extension Under Beam 9.8 8H: Straddle Underside Beam w/Trapeze 9.9 8J: Lateral Strut

10.0 TEE POLES

10.1 9A: Structural Tee Pole 10.2 9B: Tee Pole 4” Diameter Pipe 10.3 9C: Tee Pole 6” Diameter Pipe 10.4 9D: Offset Tee Pole 10.5 9E: Pipe Stand 10.6 9F: Angle Pipe Stand

11.0 MISC. UTILITY BENTS

11.1 10A: Single Tier Support From Floor

12.0 PLATE MOUNTED ON CONCRETE

12.1 11A: Plate Mounted on Concrete 12.2 11B: FRP Vessel Lug

13.0 U-DRAIN SUPPORTS

13.1 12A: U-Drain Support

13.2 12B: U-Drain Support (FRP & HDPE Pipe)

14.0 SHIM STEEL

14.1 13A: Shim Steel

15.0 SUPPORT FOUNDATIONS

15.1 14A: Pipe Stanchion Foundation 15.2 14B: Pipe Support Pier 15.3 14C: Pipe Stanchion on Concrete Slab

16.0 PIPE STAND

16.1 15A: Pipe Stand 4” and Smaller Pipe


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17.0 ACCEPTABLE CONNECTION DETAILS

17.1 Connection Details 1 of 2 17.2 Connection Details 2 of 2


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1.0 Design Rules for Supplemental Steel

1. The pipe support contractor can usually use existing steel or provide relatively light steel members for the piping supports. SCS Engineering need not be involved unless the loads are greater than 3000 lb or introduce a moment greater than 1000 ft-lb into the structure. When supporting from bar joist, the pipe support contractor shall coordinate with SCS Engineering any loads which exceed 500 lb. These loads shall be applied at panel points only. Pipes shall not be supported from building girts.

2. When loads exceed 3000 lb or 1000 ft-lb, coordination with the SCS Engineering Civil

Department is necessary. The SCS Engineering Civil Department will analyze the building frame, pipe bridge, or support structure for its ability to support the loads. If the investigation requires that the support structure be modified or reinforced to accommodate the piping loads, the modifications will be shown on the structural drawings. The SCS Engineering Civil Department will also show supplemental steel for piping supports meeting the above load criteria where structural drawings have been prepared for buildings, pipe bridges, and other structures.

3. Pipe bridges, T-poles requiring foundations or exceeding the limits of 9A, 9B, or 9C, and

sleeper-type supports will be designed by the structural department and shown on structural drawings.

4. As the piping analysis problems are completed, data will be transmitted in writing to the pipe

support contractor. This data will consist of isometrics of the piping with locations, support supplemental steel configurations, and loads. The pipe support contractor and SCS Engineering should hold a periodic review be to evaluate the supplemental steel added for piping supports.

5. Standard structural connection details are shown and may be used at the contractor’s option.

Structural connections should be chosen to minimize fit-up and field welding.

6. No supplemental steel member shall be added to roofing trusses or light weight Z purlins without consulting SCS Engineering.

7. Whenever welds are made to galvanized steel, the area must be cleaned and passivated after

welding. Cold galvanized spray paint (Galvicon or equal) shall be applied to the area. 8. Stop plates (1/4 in thick plate minimum) must be added to the end of steel members where

the pipe rests on top of a steel section with no other lateral restraint.

9. The stop plate shall be eliminated when the pipe support on the supplemental steel is an anchor or a guide.

10. SCS Engineering and the pipe support contractor must agree to any deviation to items 1

through 9 prior to detailed engineering.

11. The supplemental support steel shall have a protective coating consistent with the structural steel to which it connects. Surfaces to be painted shall be cleared and coated in accordance with Technical Specification Sections 09910 (SHOP PAINTING) and 09912 (FIELD


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PAINTING). Surfaces to be galvanized shall be cleaned and coated in accordance with Section 09915 (HOT DIP GALVANIZING). Field repair of damaged zinc coating shall be in accordance with ASTM A730, Section 4.2.1 and Annex A1.

12. All welds on supplemental steel shall be a minimum of 3/16 in unless noted otherwise.


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2.0 Beam to Beam


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6.0 Extended Member


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11.0 Misc. Utility Bents


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12.0 Plate Mounted on Concrete


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PLAN

ELEVATION ELEVATION


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14.0 Shim Steel


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15.0 Support Foundations


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16.0 Pipe Stand


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17.0 Acceptable Connection Details

(W/ WELDED OR BOLTED CLIP ANGLE)

(W/ WELDED OR BOLTED CLIP ANGLE & BEAM COPED)

(W/ WELDED OR BOLTED CLIP ANGLE)(W/ WELDED BASE PLATE)(W/ BOLTED GUSSET PLATE)

(W/ BOLTED CLIP ANGLE)(W/ WELDED CLIP ANGLE)


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(WELDED OR BOLTED)(WELDED OR BOLTED)(W/ CLIP ANGLES)

SOUTHERN COMPANY SERVICES M-2-3ENGINEERING STANDARDS AND GUIDELINES APPENDIX CMECHANICAL FRP PIPE SUPPORTS

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Appendix CFRP Standard Support Details

Index

1.0 Introduction

1.1. Purpose1.2. Scope

2.0 Codes and Standards

3.0 Design Criteria and Guidelines

3.1. General Design Consideration3.2. FRP Pipe Supports3.3. Supplementary Steel3.4. FRP Pipe Support Spacing

4.0 General Notes for FRP Pipe Supports

5.0 Rigid Supports

5.1. FSR-1: Fiberglass Pipe Cradle Support, 1”-4”5.2. FSR-2: Fiberglass Pipe Cradle Support, 6”-42”5.3. FSR-3: Fiberglass Insulated Pipe Support, 2”-42”5.4. FSR-4: Valve/Pipe Flange Support, 2”-42”5.5. FSR-5: Light Duty Fiberglass Pipe Hanger, 2”-20”5.6. FSR-6: Fiberglass Pipe Component Hanger, 2”-42”5.7. FSR-7: Fiberglass Pressure Pipe Clamp Hanger, 2”-42”5.8. FSR-8: Fiberglass Pipe Riser Hanger, 2”-42”5.9. FSR-9: Component Riser Support, 2”-42”5.10.FSR-10: Fiberglass Pipe Riser Support, 2”-42”5.11.Detail-FSR-11: Stanchion Flange Support, 2”-42”

6.0 Guide Supports

6.1. FSG-1: Fiberglass Pipe Cradle Guide, 1”-4”6.2. FSG-2: Fiberglass Pipe Support Guide, 6”-42”6.3. FSG-3: Fiberglass Insulated Pipe Support Guide, 2”-42”6.4. FSG-4: Valve/Pipe Flange Guide, 2”-42”6.5. FSG-5: Fiberglass Pipe Riser Guide, 2”-42”6.6. FSG-6: Fiberglass Pipe Braced Hanger Guide


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7.0 Anchored Supports

7.1. FSA-1: Fiberglass Pipe Anchor, 2”-4”7.2. FSA-2: Fiberglass Pipe Anchor, 6”-42”7.3. FSA-3: Fiberglass Insulated Pipe Anchor, 2”-42”7.4. FSA-4: Valve/Pipe Flange Anchor, 2”-42”7.5. Detail-FS1: Fiberglass Pipe Shear Collar


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FRP PIPE SUPPORTS

1.0 Introduction

1.1 Purpose

The purpose of this chapter is intended to serve as a guide to the proper use of pipe hangers and supports of fiber glass piping system. The document is not intended to supersede project specific design criteria but to reflect Mechanical Design Standards.

1.2 Scope

This standard shall apply to pipe supports for FRP piping systems ranging in size up to 42 inches, unless noted otherwise.

Design of FRP pipe supports shall be the responsibility of Design Engineering. Design criteria and guidelines are given in Section 3.0 of this Appendix C. FRP pipe supports shall be specified after a thorough support evaluation or pipe stress analysis has been performed, unless noted otherwise.

NOTEFRP piping systems containing FRP supports is typically designed as an

engineered system of supports. Design of FRP engineered supports will include standard FRP pipe supports represented in the following sections.


FRP pipe support design is governed by the codes and standards that apply to the FRP piping system. The designer should be familiar with the support design portions of the applicable codes. The following standards are applicable to FRP piping systems and FRP pipe support systems.

American Society of Mechanical Engineers.

ASME Standard B31.3 – Process Piping(Addresses primarily metallic piping, but it is expanded to cover Non-metallic piping including thermoplastic and thermo set piping system.)

NBS Voluntary Product Standard PS 15-69.


3.1 General Design Consideration

The principles of design and analysis for FRP pipe differ considerably from the principles of design for metallic pipe. The analysis of steel pipe normally begins with maximum flexibility and the final support-guide-anchor design ends when allowable stresses and loads are achieved.


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When analyzing FRP pipe, the analysis normally begins with a semi rigid system and the final support-guide-anchor configuration is established when the minimum stress condition is reached, based on the available structural support structures. Long straight runs can use a fully anchored approach for smaller diameter pipe (<8”). Large diameter FRP pipe attached to pumps and blowers should be reviewed relative to equipment allowable.

Formal pipe stress analysis of FRP piping system based on pipe wall thickness, design temperature, design pressure and fluid content establishes FRP pipe support design criteria and FRP pipe support types to be used. Pipe stress analysis determines FRP pipe support span, guide spacing, offset leg and anchor locations.

Supports shall be designed for the most severe conditions of coincident pressure, weight, temperature, and any fluid dynamic events. In addition, piping exposed to wind, snow, ice, earthquake, or other natural phenomena, including solar temperature up to 140ºF empty, shall be considered and supports shall be designed for such loading.

FRP pipe supports, hanger components, support spacing, and installation shall meet the requirements specified by the FRP pipe manufacturer.

3.2 FRP Pipe Supports

The basic types of supports are weight supports, guide supports and anchor supports.

Piping shall be supported using standard pipe supports, unless required otherwise.

FRP Supports shall be spaced to meet the requirements of the recommended hanger and support spacing chart or as calculated by the stress engineer.

Supports shall be located close to concentrated loads such as valves, flanges, branch connections, short risers, and other components in order to keep bending stresses to a minimum. Heavy valves must be supported independently. For supports near or around a bend, reduce the hanger spacing by 1/3.

All valves and inline components shall be supported independently of the pipe. Heavycomponents such as actuators and/or external loads shall be anchored to prevent pipe damage.

Pipe hangers shall be capable of supporting the pipe in all conditions of operation. They shall allow free expansion and contraction of the piping, and prevent excessive stress resulting from transferred weight being induced into the pipe or connected equipment.

No pipe shall be supported from pipe bridge cross-brace (WT’s or L’s), staircase landings, handrails, or handrail supports.

Wherever space permits, hanger rod shall be provided with a turnbuckle for vertical adjustment after erection.


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3.3 Supplementary steel

Building steel and pipe rack steel shall be used for support where practical.

Supplementary steel shall be designed and provided where building steel or pipe rack steel is not available. Refer to Appendix B of this Standard for supplemental steel requirements.

Supplementary steel shall be designed for the larger of the pipe design loads or the hydrostatic test load.

Supplementary steel shall be designed in accordance with the requirements of the AISC Manual of Steel Construction.

3.4 FRP Pipe Support Spacing

Horizontal FRP piping shall be supported to prevent excessive sag, bending and shear stresses in the piping. Special design consideration shall be given where components such as flanges and valves impose concentrated loads.

Vertical FRP pipe shall be supported to prevent the pipe from being overstressed due to the combination of all loading effects.

Where stress analysis calculations are not made, FRP pipe manufacturer recommended maximum spacing requirements, reduced by 20%, shall be used.

The following table of recommended FRP pipe support spacing shall be used for FRP pipes manufactured by Reinforced Plastic Systems Inc. only. This table is based on the criteria of Strength Ratio (SR) in structure greater than 1.6; and deflection less than 0.50 inch.

TABLERecommended FRP Pipe Support Spacing

Support spacing (ft.) @ 150 deg. F0

For RPS P150 & A150 piping

Nominal Pipe Diameter

Single SpanSG=1.0

Single SpanSG=1.3

Continuous SpanSG=1.0

Continuous SpanSG=1.3

1” 7.0 7.0 9.0 9.01-1/2” 7.3 7.1 9.3 8.7

2” 8.0 7.5 9.8 9.23” 8.4 7.7 10.3 9.54” 8.7 8.0 10.7 9.86” 10.9 10.0 13.3 12.28“ 10.9 10.0 13.1 12.0

10“ 13.0 11.6 15.6 13.912” 13.7 13.0 16.4 15.6


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14“ 13.7 13.0 16.4 15.616” 15.2 14.0 18.2 16.818” 16.7 15.0 20.0 18.020” 17.4 15.5 20.9 18.624” 19.1 17.0 22.9 20.430” 20.5 18.3 24.6 22.036” 22.1 19.7 26.5 23.6

CAUTION NOTE: Above values shall not be used for spans having concentrated loads, such as valves,branch connections, etc., where excessive vibration or pulsation is expected. Support spans, near or around a bend, shall be reduced by 1/3.


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4.0 General Notes for FRP Pipe Supports

1. Hangers shall be fabricated from 3/16”, 1/4”, 3/8”, or 1/2” thick plate per ASTM A36, unless noted.

2. All hanger hardware shall be galvanized unless otherwise specified. Where galvanizing is damaged by welding and/or by drilling, one coat of a non-toxic, zinc-rich compound (such as “DRYGALV” by American Solder and Flux Company or approved equivalent) at 5.0 mils dry film thickness shall be applied. Support assembly shall not be installed until repair coating is cured.

3. Supports shall be designed to fit the O.D. of the pipe and must be located to clear all pipe wraps at fittings and shop or field joints.

4. FSG-1 guides shall have special u-bolt clearances as indicated in the detail. Under no circumstances shall FRP pipe be clamped tightly by u-bolt or supported without a cradle.

5. All cradle or clamp type supports that contact the O.D. of the pipe shall include an elastomeric liner bonded to the cradle.

6. Flanged component supports, such as FSR-4, shall be used to support components such as valves. The length of flange bolts must be increased approximately 1/2”. All thread rodsshall be used in lieu of bolts for ease of installation, unless stated otherwise.

7. Component supports 12” diameter and larger shall be scalloped to provide clearance for the flange hub reinforcement specified in National Bureau of Standards Voluntary Product Standard PS-15-69.

8. Support details call-out “Jove # FS-XX” refers to support model number published by JTI Manufacturing, Inc., Birmingham, AL, and is for reference only. FRP supports by Britt Engineering of Birmingham, AL and Maverick Applied Science of Palmetto, FL are also acceptable; any others must be approved in writing by Southern Company Mechanical Department.

9. Rod hanger component designations for support details FSR-5, FSR-6, FSR-7, FSR-8 and FSG-6 shall be based on the Anvil, formerly “Grinnell”, numbering system.

10. FRP pipe supports with an “S” suffix (ex. FSR-2S, FSG-2S, etc.) are non-standard supports. If dimensions are different than shown in standard detail, dimensions shall be specified with non-standard call-out (etc. FSR-2S, L=15”).


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SOUTHERN COMPANY SERVICES M-2-3ENGINEERING STANDARDS AND GUIDELINES APPENDIX DMECHANICAL HDPE PIPE SUPPORTS

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Appendix D:HDPE Standard Support Details


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Appendix D:HDPE Standard Support Details

Index1.0 Introduction

1.1. Purpose1.2. Scope



3.1. General Design Consideration3.2. HDPE Pipe Supports3.3. Supplementary Steel3.4. HDPE Pipe Support Spacing

4.0 General Notes for HDPE Pipe Supports

5.0 Rigid Supports

5.1. HPR-1: HDPE Pipe Rigid Support, 2”-36”5.2. HPR-2: HDPE Pipe Rigid Support, 2”-36”5.3. HPR-3: HDPE Pipe Riser Support, 2”-12”5.4. HPR-4: HDPE Pipe Rod Hanger, 2”-20”5.5. HPR-5: HDPE Pipe Component Hanger, 2”-36”5.6. HPR-6: HDPE Pipe Riser Component Support, 2”-36”5.7. HPR-7: HDPE Pipe Rod Hanger, 2”-20”5.8. HPR-8: HDPE Pipe Riser Hanger, 2”-16”

6.0 Guide Supports

6.1. HPG-1: HDPE Pipe Guide, 2”-36”6.2. HPG-1A: HDPE Pipe Guide, 2”-16”6.3. HPG-2: HDPE Pipe Guide, 2”-36”6.4. HPG-3: HDPE Pipe Riser Guide, 2”-6”6.5. HPG-4: HDPE Pipe Riser Guide, 8”-12”

7.0 Anchor Supports

7.1. HPA-1: HDPE Pipe Friction Anchor, 2”-36”7.2. HPA-1A: HDPE Pipe Friction Anchor, 2”-16”7.3. HPA-2: HDPE Pipe Friction Anchor, 2”-36”7.4. HPA-3: HDPE Pipe Riser Anchor, 2”-6”7.5. HPA-4: HDPE Pipe Riser Anchor, 8”-12”7.6. HPA-5: HDPE Pipe Anchor, 2”-36”7.7. HPA-6: HDPE Pipe Anchor, 2”-36”7.8. HPA-7: HDPE Pipe Riser Component Anchor, 2”-36” 7.9. HPA-8: HDPE Pipe Anchor, 2”-36”


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7.10. HPA-9: HDPE Pipe Anchor, 2”-36”7.11. HPA-10: HDPE Pipe Positive Anchor, 4”-16”


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HDPE PIPE SUPPORTS

1.0 Introduction

1.1 Purpose

The purpose of this chapter is intended to serve as a guide to the proper use of pipe hangers and supports of High Density Polyethylene, normally called HDPE piping system. The document is not intended to supersede project specific design criteria but to reflect Mechanical Design Standards.

1.2 Scope

This standard shall apply to HDPE pipe supports for piping systems ranging in size up to 36 inches, unless noted otherwise. Design of HDPE pipe supports shall be the responsibility of Design Engineering. Design criteria and guidelines are given in Section 3.0 of this Appendix D.

2.0 Standards

HDPE pipe support design and installation shall be in accordance with the pipe manufacturer’s recommendation. This standard gives general guidelines applicable to nonmetallic piping system and pipe support design in accordance with

American Society of Mechanical Engineers,ASME Standard B31.3 – Process Piping.


3.1 General Design Consideration

Supports shall be designed for the most severe conditions of coincident pressure, weight, temperature, and any fluid dynamic events. In addition, piping exposed to wind, snow, ice, earthquake, or other natural phenomena shall be considered and supports shall be designed for such loading.

Thermal expansion and contraction must be considered during piping system design. These design parameters shall be incorporated into the installation specifications. Thermal expansion of HDPE is much greater than that of steel. Allowances must be made to accommodate or control this expansion. HDPE piping supports shall be designed for the maximum operating conditions, including thermal effects.

HDPE pipe supports, hanger components, support spacing, and installation shall meet the requirements specified by the HDPE pipe manufacturer.


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Pipe supports shall be located close to concentrated loads such as valves, flanges, branch connections, short risers, and other components in order to keep bending stresses to a minimum. Heavy valves must be supported independently. Heavy fittings and metal flanged connections should be supported on either side.

All valves and inline components shall be supported independently of the pipe. Heavycomponents such as actuators, and/or external loads shall be anchored to prevent pipe damage.

Where the pipeline is designed to move due to expansion, a sliding support, capable of guidingwithout restraint in the direction of movement, shall be provided.

For buried HDPE applications, soil friction along the pipe length, combined with moderate or low temperature change, shall be sufficient to prevent dimensional change and expansion movement, unless determined otherwise. Thrust blocks for underground pipelines shall be utilized on underground pipelines where water hammer and temperature changes are anticipateddue to a transient analysis.

HDPE piping shall be protected against excessive bending and shear loads where pipes emerge from structures as walls or casings; in addition to rigid connections such as flanges and mechanical joints.

3.2 HDPE Pipe Supports

The basic types of supports are weight supports, guide supports and anchor supports.

Above grade HDPE applications require non-continuous support. Such applications involve piping in a rack or trestle, on sleepers, or suspended from an overhead structure. Supportstructures must provide proper pipeline support, accommodate thermal expansion and contraction movement, and provide support spacing that limits vertical deflection between supports within acceptable limits. See section 3.4 of this Appendix for HDPE spacing requirements.

The weight of the pipe and the contents must be distributed over a broad surface. Commercial pipe supports such as u-bolts, narrow strap-type hangers, and roller type supports are unsuitable unless modified for width and cradling. Narrow support surfaces can produce high concentrated stress, and lead to pipeline failure.

Pipes supported in an overhead rack shall be designed for both support spacing and thermal length change. Support beams shall be spaced according to vertical deflection limits. Pipe supports should be allowed to move along support beams.

Pipe hangers shall be capable of supporting the pipe in all conditions of operation. They shall allow free expansion and contraction of the piping, and prevent excessive stress resulting from transferred weight being induced into the pipe or connected equipment.


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HDPE piping shall be protected against excessive bending and shear loads where pipes emerge from structures such as walls or castings, in addition to rigid connections such as flanges and mechanical joints.

3.4 HDPE Pipe Support Spacing

Horizontal HDPE pipe shall be supported to prevent excessive sag, bending and shear stresses in the piping. Special design consideration shall be given where components such as flanges and valves impose concentrated loads.

Vertical HDPE pipe supports shall be spaced to prevent the pipe from being overstressed due to the combination of all loading effects.

HDPE supports shall be spaced to meet the requirements of the recommended hanger and support spacing chart issued by the pipe manufacturer.

The following table of recommended HDPE pipe support spacing is given by Performance Pipe Inc. HDPE pipe manufactured by Performance Pipe Inc. or engineer approved equal must meet the support spacing shown in the table. Performance Pipe recommends that the allowable long-term deflection between supports should not exceed 1 inch.

TABLERecommended HDPE Pipe Support Spacing

Support spacing (ft.) @ 730F/1000F/1400F filled with water

IPS size

OD, in. DR 7.3730F

DR 7.3 1000F

DR 7.3 1400F

DR 9730F

DR 91000F

DR 91400F

DR 11730F

DR 111000F

DR 111400F

2” 2.375 5.3 5.0 4.2 5.1 4.8 4.0 4.9 4.7 3.93” 3.500 6.4 6.0 5.1 6.2 5.9 4.9 6.0 5.6 4.84” 4.500 7.3 6.9 5.8 7.0 6.6 5.6 6.8 6.4 5.46” 6.625 8.8 8.3 7.0 8.5 8.1 6.8 8.3 7.8 6.58“ 8.625 10.1 9.5 8.0 9.7 9.2 7.7 9.4 8.9 7.5

10“ 10.750 11.2 10.6 9.0 10.9 10.0 8.6 10.5 10.0 8.412” 12.750 12.2 11.6 9.7 11.9 11.2 9.4 11.5 10.8 9.114“ 14.000 12.8 12.2 10.2 12.4 11.8 9.9 12.0 11.4 9.516” 16.000 13.7 13.0 10.9 13.3 12.6 10.6 12.8 12.2 10.218” 18.000 14.5 13.7 11.6 14.1 13.3 11.2 13.6 12.9 10.820” 20.000 15.3 14.5 12.2 14.8 14.1 11.8 14.3 13.6 11.422” 22.000 16.1 15.2 12.8 15.6 14.8 12.4 15.0 14.2 12.024” 24.000 16.8 15.9 13.4 16.3 15.4 13.0 15.7 14.9 12.526” 26.000 17.5 16.5 13.9 16.9 16.1 13.5 16.3 15.5 13.028” 28.000 17.6 16.7 14.0 17.0 16.1 13.530” 30.000 18.2 17.2 14.5 17.6 16.6 14.032” 32.000 18.8 17.8 15.0 18.1 17.2 14.434” 34.000 18.7 17.7 14.9


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36” 36.000 19.2 18.2 15.5

CAUTION NOTE: Above values shall not be used for spans having concentrated loads, such as valves, branch connections, etc., where excessive vibration or pulsation is expected. Spacing will vary for different temperature and for different fluids in the pipe.


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4.0 General Notes for HDPE Pipe Supports

1. Hangers shall be fabricated from 3/16”, 1/4”, 3/8”, or 1/2” thick plate per ASTM A36, unless noted.

2. All hanger hardware and components including bolts and nuts shall be galvanized unless otherwise specified. Where galvanizing is damaged by welding and/or by drilling, one coat of a non-toxic, zinc-rich compound (such as “DRYGALV” by American Solder and Flux Company or approved equivalent) at 5.0 mils dry film thickness shall be applied. Support assembly shall not be installed until repair coating is cured.

3. Supports shall be designed to fit the O.D. of the pipe and must be located to clear all pipe welds at fittings and shop or field joints.

4. HDPE pipe support shall have a wide strap or clamp as shown in the detail. Mechanically galvanized carbon steel bolts per ASTM A307 shall be used with washers, unless stated otherwise.

5. HDPE pipe guides must maintain clearances between pipe and a strap or clamp as indicated in the detail.

6. Flanged component supports shall be used to support components such as valves. The length of flange bolts must be increased approximately 1/2”. All thread rods shall be used in lieu of bolts for ease of installation, unless stated otherwise.

7. Support detail call-out “Jove # FS-XX” refers to support model number published by JTI Manufacturing, Inc., Birmingham, AL, and is for reference only.

8. Rod hanger component designations for support details HPR-4 and HPR-5 shall be based on the Anvil, formerly “Grinnell”, numbering system.


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5.0 Rigid Supports


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6.0 Guide Supports


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7.0 Anchor Supports


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SOUTHERN COMPANY SERVICES M-2-3ENGINEERING STANDARDS AND GUIDELINES APPENDIX EMECHANICAL FRP, HDPE GUIDELINES

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Appendix E:Pipe Support Guidelines; FRP & HDPE Pipe


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PIPE SUPPORT GUIDELINESFRP & HDPE PIPE

The selection and location of pipe supports for FRP and HDPE pipe is far more critical than for steel pipe. Due to their low modulus of elasticity and their relatively high thermal expansion rate, pipe deflections due to temperature, weight and/or gravity are much more pronounced. Care must be taken to account for and control these deflections.

In general, the Designer shall be responsible for supporting the FRP and HDPE pipe as it is routed. Consideration should be taken while routing the pipe to provide proper support, including necessary guides and anchors. Where practical, route the pipe to make use of existing building steel or pipe rack steel.

All supports shall comply with the requirements of the FRP and HDPE pipe support standards. (Reference Appendix C and D respectively, of “Pipe Hangers and Supports Standard”, M-2-3)

The Designer shall support all pipes on the isometric or orthographic drawing (if there is no iso). The piping system design will not be considered complete until all pipe supports have been located. The Checker will be responsible for checking all FRP and HDPE pipe supports as he/she checks the pipe routing. In addition, the responsible Engineer shall review the completed piping isometric or orthographic drawing to verify that all design requirements have been met, including pipe support locations.

GENERAL GUIDELINES –

1. Rods – The use of rod type hangers should be avoided or minimized in the support of FRP and HDPE pipe. Resting or sliding supports, which provide more stability and a location capable of anchoring or guiding the pipe, are preferred. However, rod assemblies may be used as intermediate supports between two resting supports, where practical. Depending on pipe size, most rod assemblies require at least 24” to 30” minimum between pipe centerline and bottom of steel. (Note: Air and gas systems may be rod hung if it is more practical.)

2. Point Loads – FRP and, HDPE pipe should not be point loaded. That is, the load must be

spread out on the pipe to avoid punch and shear loads, which are significant problems with softer materials such as FRP and HDPE. Avoid or cushion sharp, irregular edges at any steel/pipe interface.

FRP pipe should always be supported with saddles or cradles to spread the load. Isolate FRP from steel clamps and hangers with a 1/8” thick elastomeric lining.

HDPE pipe can rest directly on support steel as long as the steel is a minimum of 4” wide. Support brackets, hangers and clamps should be the greater of 4” or one-half pipe diameter in width. Standard pipe clamps and u-bolts are permitted, but should be isolated from the pipe with an isolation pad similar in size to the brackets and clamps mentioned above. (Ref. M-2-3, Appendix D, General Notes.)


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3. Risers - Long risers (>10’) should be supported independently of the horizontal pipe. If not possible, locate supports at top and bottom of the riser to divide the load. Generally, long risers should be guided at every floor penetration, or at least every 15 to 20 ft.

4. Pumps - Pump discharge lines must be restrained. Rod type hangers shall not be used on pump discharge piping. The top elbow (first elbow) of all pump discharge lines must be braced. On larger lines (>10” Φ), the first two elbows off the pump should be restrained. In addition, pumped lines should be guided near each turn and long runs should be anchored near the middle.

Note: Due to the higher coefficient of thermal expansion for FRP, large diameter (>14”Φ) water and slurry pump discharge lines with operating temperatures in excess of 100°F should be reviewed by the Stress Engineer.

5. Valve Stations - Valve stations should be anchored at one end and guided at the other. If possible, locate valve stations approximately 2’-0” above the floor for optimum support and accessibility. Heavy steel valves must be independently supported at the valve inlet and outlet, in such a manner as to facilitate valve removal. Pipelines dropping into and coming up out of valve stations should be braced near the top elbow.

6. Thermal Expansion – As mentioned before, consideration must be given for thermal

expansion of FRP and HDPE pipe. Supports, sleeves, penetrations and pipe to pipe spacingmust allow for expansion. Even for ambient conditions, thermal expansion may be significant on a hot summer day if the pipe is long enough. Be especially aware on bridges.

FRP GUIDELINES

Support location, selection and installation are extremely critical for FRP pipe. Most FRP failures occur because of improper pipe support. Unlike steel, FRP is an orthotropic material, meaning that its mechanical properties are not the same in all directions. Thus, FRP behaves differently than steel when loaded. FRP also has a modulus of elasticity that is only about 5-8 % of steel. This coupled with a thermal expansion that is roughly 2 to 2 ½ times that of carbon steel makes support selection for FRP piping systems critical.

In the layout and design of FRP piping systems, there are three typical design methods that may be employed by the Designer: 1. Flexible, 2. Rigid, or 3. Semi-rigid.

Flexible System

The flexible system approach was used for many years in the design and support of FRP pipe. In this system, the FRP piping is neither anchored nor guided and is allowed to freely expand. (Fig. 1) While appropriate for steel pipe, the flexible system normally results in overstressed FRP fittings and joints. Also, in pressurized systems, the dynamic forces are totally undamped and the system is subject to large deflections from vibration and shock. The flexible system is most susceptible to catastrophic


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failure and shall not be employed to support FRP piping systems. The flexible system is included in this discussion as an example of what not to do.

Fig. 1 – Flexible SystemRigid System

The rigid system or anchor to anchor system (Fig. 2) as sometimes called, utilizes anchors at each end of a pipe run and on either side of any change in direction to prevent or control linear expansion due to temperature and pressure. This is an acceptable approach with FRP (and HDPE) as opposed to steel pipe because of the relatively low compressive modulus of elasticity. The resulting forces are absorbed into the anchors and the pipe itself, thus eliminating the stresses on the joints and elbows, where most catastrophic failures occur. This system also has the advantage of controlling the dynamic effects of vibration. The down side of this approach is that pipe greater than 8”Φ generates forces on the anchors that are too large for the supporting structure to handle. However, for smaller diameter piping, this is an acceptable method of design.

Fig. 2 – Rigid (Anchor-to-Anchor) System


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If this method is to be used, consult with the appropriate Engineer who shall perform anchor load calculations and minimum guide spacing calculations. To prevent “column buckling” the location and spacing of intermediate guides (multiple) is very critical and must be calculated.

Semi-Rigid System

When the “rigid system” approach is undesirable, the semi-rigid system may be used. This system is the most common method used to restrain FRP pipe. In the semi-rigid system (Fig. 3), anchors and guides are located to control expansion and ensure that the “off-set” legs are not overstressed. Generally, the change in direction between the “expansion” leg and the “off-set” leg should occur at an elbow and not at a tee or saddle.

Fig. 3 – Semi-Rigid System

The required length of the “off-set” leg is a function of pipe diameter, length of the “expansion” leg, the coefficient of thermal expansion, the elastic modulus, the maximum allowable bending moment and the net allowable tensile stress. Thus, the required off-set should be verified by calculation by the appropriate Engineer. However, for general purposes, the values listed in Table 1 may be used by the Designer to lay out the pipe off-sets and anchor and guide locations. For sizes outside the range of the chart, consult with the appropriate Engineer.


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Table 1 – Required Off-set for Thermal Expansion(Ref. RPS “Design Manual”)

Required “Off-set” @ Elbow, (ft)ID Thermal Expansion, (in)(in) 0.2 0.4 0.6 0.8 1.0 2.01 1.9 2.7 3.3 3.8 4.2 5.9

1.5 2.3 3.3 4.0 4.6 5.2 7.32 2.8 4.0 4.9 5.7 6.4 9.03 4.0 5.7 6.9 8.0 8.9 12.64 5.3 7.4 9.1 10.5 11.8 16.66 5.9 8.3 10.2 11.7 13.1 18.68 7.7 10.9 13.4 15.5 17.3 24.410 8.4 11.9 14.6 16.9 18.8 26.712 9.1 12.8 15.7 18.1 20.3 28.7

Coefficient of Thermal Expansion for FRP (αFRP, in/in °F) αFRP = 1.35x10-5 in/in°F x 12 in/ft x ΔT, °F αFRP @ 130°F = 0.00972 in/ftThermal Expansion = Length (L1, L2, etc.) x αFRP, in/ft

Hanger Spacing – Generally, FRP pipe supports shall be located such that the maximum deflection (due to gravity) between supports is limited to < ½” and the maximum bending stress (due to gravity) is less than the Net Allowable Tensile Stress, σA (psi). Since this information is not readily available to the Designer, the FRP manufacturer’s recommended support spans or the recommended support spans (whichever is less) in M-2-3, Appendix C may be used.

Exceptions or adjustments to these guidelines include:1. Horizontal 90 deg. turns - reduce span by 30 %.2. Horizontal runs with vertical offset (risers) between supports - reduce span by 30%.

(Try to locate support near offset.)3. Heavy inline components, such as steel valves, strainers, etc. must be supported independently. (Ref. M-2-3, Appendix C for details of typical component supports.)4. For situations where longer spans are required, consult the appropriate Engineer. Specific

calculations may support a longer span.

Support Locations - Study structural steel locations to determine optimum support locations. Anchors and guides should be located at bay line beams and columns, where possible. When support is required and there is no structural steel available, use auxiliary steel in accordance with the “Pipe Hangers and Supports Standard”, M-2-3, Appendix B.

Guides and Anchors – With FRP pipe, guides and anchors are installed to control the effects of thermal expansion as well as flow induced dynamic movements. Vibration and dynamic movement are especially destructive to FRP pipe. Therefore, more guides and anchors will be required for FRP pipe than for a similar size steel line. The following are some guidelines for locating guides and anchors:


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1. Rigid SystemA. Anchors shall be located adjacent to each change in direction. (Fig. 1)B. Guide spacing will be calculated and guides shall be located accordingly.

(These locations are critical.)

2. Semi-Rigid SystemA. Locate a guide or an anchor as close to an elbow as the thermal expansion will

allow (ref. Table 1). B. Locate an anchor in each significant straight run (> 20-25 ft).C. On long runs, after the first anchor/guide near an elbow, at least every 4th support

should be a guide.

HDPE GUIDELINES

While the support of above ground HDPE is not as critical as for FRP, HDPE support requirements differ greatly from steel pipe. Due to HDPE’s relatively low elastic modulus (~ 1/300 of the modulus of steel) and very large coefficient of expansion (~ 15 times the expansion of carbon steel) and the fact that HDPE properties vary significantly with temperature, HDPE requires much more support than steel or FRP pipe. Insufficient support will result in significant sag and lateral squirm. However, due to its toughness, catastrophic failures are not nearly as common due to improper support as they are for FRP.

Hanger Spacing – The primary concern in the support of HDPE pipe is to control vertical deflection due to gravity. Performance Pipe recommends limiting gravity deflection to less than 1”. This should be considered a maximum, and in some cases should be kept to ½” or less. The allowable spans in the span chart in the “Pipe Hanger and Support Standard”, M-2-3, Appendix D are temperature sensitive. Spans are given for three different temperatures. Exceptions or adjustments to these guidelines include:

1. Horizontal 90 deg. turns - reduce span by 30 %.2. Horizontal runs with vertical offset (risers) between supports - reduce span by 50%.

(Note, try to support risers independently from the horizontal pipe. However, if necessary, support the top of the riser adjacent to the elbow.)

3. Heavy inline components, such as steel valves, strainers, etc. must be supported independently. (Ref. M-2-3, Appendix C and/or D for details of typical component supports.)

4. For temperatures greater than 150°F, continuous support is required.

Support Locations - Study structural steel locations to determine optimum support locations. Anchors and guides should be located at bay line beams and columns, where possible. When support is required and there is no structural steel available, use auxiliary steel in accordance with the “Pipe Hangers and Supports Standard”, M-2-3.

Guides and Anchors – With HDPE, guides and anchors are installed to control the effects of thermal expansion as well as flow induced dynamic movements. Due to the low elastic modulus of


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HDPE (~100,000 psi), anchor and guide loads for off-set HDPE systems are usually minimal and can be ignored, except for large diameter pipe (>14”). Like FRP, HDPE will require more guides and anchors than for a similar size steel line. As a general rule, each straight run of pipe should be anchored, preferably near the center and guided within 5 feet of an elbow. For long runs, every other support between the anchor and end guide should be a guide. (Fig. 4) For pipe 4”Φ and smaller, consider guiding at every support. If an anchor to anchor approach is used, similar to the Rigid System design discussed for FRP, reference Table 2 for anchor loads and minimum guide spacing. The data in Table 2 is based on a 100°F design temperature and a 60°F installation temperature.

Fig. 4 – HDPE Guides and Anchors

Table 2 – HDPE Anchor to Anchor Loads and Guide Spacing


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(Ref. Performance Pipe “Bulletin PP 109)

APW IWALL AREA MOM OF INERTIA

(in2) (in4) (in) (ft)2 11 2.375 0.216 1.943 1.46 0.86 289 561 28.4 2.42 9 2.375 0.264 1.847 1.75 0.99 345 670 27.8 2.33 11 3.500 0.318 2.864 3.18 4.07 627 1218 41.9 3.53 9 3.500 0.389 2.722 3.80 4.67 749 1455 41.0 3.44 11 4.500 0.409 3.682 5.26 11.11 1036 2013 53.8 4.54 9 4.500 0.500 3.500 6.28 12.76 1238 2405 52.8 4.46 11 6.625 0.602 5.420 11.40 52.19 2246 4363 79.2 6.66 9 6.625 0.736 5.153 13.62 59.96 2684 5214 77.7 6.58 11 8.625 0.784 7.057 19.31 149.92 3807 7394 103.1 8.68 9 8.625 0.958 6.708 23.08 172.24 4549 8837 101.1 8.4

10 11 10.750 0.977 8.795 30.00 361.78 5914 11487 128.6 10.710 9 10.750 1.194 8.361 35.86 415.65 7067 13727 126.1 10.512 11 12.750 1.159 10.432 42.21 715.90 8319 16159 152.5 12.712 9 12.750 1.417 9.917 50.44 822.50 9942 19310 149.5 12.514 11 14.000 1.273 11.455 50.89 1040.69 10030 19482 167.4 14.014 9 14.000 1.556 10.889 60.82 1195.65 11987 23282 164.2 13.716 11 16.000 1.455 13.091 66.47 1775.38 13101 25446 191.3 15.916 9 16.000 1.778 12.444 79.43 2039.73 15656 30410 187.6 15.618 11 18.000 1.636 14.727 84.12 2843.81 16580 32205 215.3 17.918 9 18.000 2.000 14.000 100.53 3267.26 19815 38487 211.1 17.6

DATA INPUTTEMP MAXIMUM, (°F): 100 EC, @ 80 F, (psi): 54,750TEMP MINIMUM, (°F): 10 ET, @ 35 F, (psi): 85,075TEMP AMBIENT, (°F): 60 0.00009

HYDROSTATIC DES. BASIS = HDB = 1600.00fe = ENVIRONMENTAL DESIGN FACTOR = 0.50fT = SERVICE TEMP DES. FACTOR @40 F = 1.20fT = SERVICE TEMP DES. FACTOR @50 F = 1.14CALCS

σc=LONGITUDINAL COMP. STRESS, (psi) = EαΔT = 197.10σca=ALLOWABLE LONG COMP STRESS, (psi) = 960σt=LONGITUDINAL TENSILE STRESS, (psi) = 382.84σta=ALLOWABLE LONG TENSILE STRESS, (psi) = 912

FORMULASF= ANCH FORCE = σc,t X APW = GUIDE SPACING = (π2I)/NαΔTAPW) (N= SAFETY FACTOR = 2)

ID (in)

α, (IN/IN-°F):

NOM Φ (in)

DR NUM

OD (in)

THK (in)

ANCHOR FORCEFCOMP

(lbs)FTENSILE

(lbs)

LG GUIDE SPACING

Note: Calculation procedure, material properties and formulas are from Performance Pipe technical bulletin “PP 109”, Revision Date October, 2002

m-2-3 hangers and supports

Documents

building pipe rack structure

heavy inline components

low elastic modulus

pump discharge lines

pipe rack structure

maximum allowable stress

bay line beams

piping stress analysis