construction requirements for communication installations

7/25/2019 Construction Requirements for Communication Installations

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Note: The source of the technical material in this volume is the Professional

Engineering Development Program (PEDP) of Engineering Services.

Warning: The material contained in this document was developed for Saudi

Aramco and is intended for the exclusive use of Saudi Aramcos

employees. Any material contained in this document which is notalready in the public domain may not be copied, reproduced, sold, given,

or disclosed to third parties, or otherwise used in whole, or in part,

without the written permission of the Vice President, Engineering

Services, Saudi Aramco.

Chapter : Communications For additional information on this subject, contact

File Reference: COP10106 J.S. Phillips on 873-0228

Engineering EncyclopediaSaudi Aramco DeskTop Standards

Construction Consideration


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Engineering Encyclopedia Communications


Saudi Aramco DeskTop Standards

CONTENTS PAGES

CONSTRUCTION REQUIREMENTS OF CIVIL WORK FOR

STRUCTURES ......................................................................................................1

Conduits .....................................................................................................1

Plastic Conduit - Types and Use .....................................................1

Manholes ....................................................................................................8

Types and Dimensions....................................................................9

Laterals............................................................................................9

Termination...................................................................................10

Grounding .....................................................................................12Sump.............................................................................................12

Pulling-In Irons.........................................................................................12

Ladders .........................................................................................14

Lids ...............................................................................................14

Racks.............................................................................................16

Pedestal Installations ................................................................................18

Direct Buried Cable..................................................................................21

Buried Service Wire......................................................................27

Installing Cable Markers ..........................................................................28

Marking and Identification ...........................................................28

Placement in Trenches ..................................................................34

Separation.................................................................................................34

SPLICING CABLE: METHODS, MATERIALS, AND NUMBERING

CODES ................................................................................................................39

Cable Numbering and Count Identification..............................................39Methods....................................................................................................44

Straight Splices .............................................................................45

Butt Splices...............................................................................................46


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Saudi Aramco DeskTop Standards

Materials...................................................................................................48

Splice Closures .............................................................................48

Connectors/Bonding Clips ............................................................48

BURIED CABLE: SPLICING, BONDING, AND SEPARATION

REQUIREMENTS...............................................................................................51

Splicing.....................................................................................................51

Direct Buried ............................................................................................51

In Pedestal.....................................................................................52

Bonding and Grounding ...........................................................................52

Separation.................................................................................................54

TECHNIQUES AND DESIGN CONSIDERATIONS FOR PULLING,

RACKING, SPLICING, AND BONDING AND GROUNDING OF

UNDERGROUND CABLE .................................................................................55

Pulling ......................................................................................................55

Standards.......................................................................................56

Procedures.....................................................................................58

Racking.....................................................................................................61

Standards.......................................................................................61

Procedures.....................................................................................61

Hardware Requirements................................................................66

Safety........................................................................................................68

Splicing.....................................................................................................68

Bonding and Grounding ...........................................................................71

GLOSSARY ........................................................................................................72


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Saudi Aramco DeskTop Standards 1

CONSTRUCTION REQUIREMENTS OF CIVIL WORK FOR STRUCTURES

The following civil work for structures will be covered in this section:

Conduits

Manholes

Pedestal Installations

Direct Buried Cable

Installing Cable Markers

Separation

Conduits

The standards to be used for conduits are GTE Section No. 622-020-100 and Saudi Aramco

Engineering Standard (SAES)-T-911. The various types of conduit materials include plastic

and steel for Saudi Aramco applications. Single-bore, plastic conduit is the preferred type of

conduit for most of Saudi Aramcos needs.

Plastic Conduit - Types and Use

The type of conduit that is preferred for use in constructing Saudi Aramco Communication

Conduit Systems is Type DB which is also referred to as Type II duct. This conduit is a thick-

wall, round plastic (PVC) conduit with one bell end. This conduit is manufactured in standard

lengths of 20ft (6m) and is designed to be direct buried as long as the minimum cover can be

obtained. This conduit must conform to NEMA Standard TC-8 (AMS#15-312-017). Type

DB conduit may be installed in areas where the conduit will be exposed to sunlight

(ultraviolet radiation) as long as the conduit is treated and the thermal expansion and

contraction of the conduit are accounted for in the design through the use of expansion joints.

Straight, plastic conduit is furnished in the type and sizes that are shown in Figure 1. One

type has a bell end or a cemented coupling on one end. The other type is a straight, two

piece, snap-together plastic duct that is used to enclose existing cable.


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Straight Plastic Conduit

Figure 1


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Conduit is to be designed and engineered with the expectation that the conduit will continue

in service for 75 to 100 years. Underground conduit must be designed to withstand external

loads to which the conduit will be subjected. These external loads are caused by the

following sources:

Weight of the backfill material.

Weight of dead loads.

Weight of live (impact) loads.

Weight of any other loads that may be applied at the surface of the fill.

Detailed construction drawings are required for the placement of conduit in the following

situations:

Crossings of bridges and culverts.

Crossings where attachment is to be made to a specially designed structure.

Crossings under railroad tracks or embankments by means of boring, jacking,

or tunneling methods.

Installations where the conduit is to be laid through unstable ground that

requires piling or other means of support.

All conduit designs must take into consideration the vulnerability to future disturbance and

the degree of mechanical protection that is needed to safeguard the conduit and cable. The

following problem areas must be considered and avoided where possible:

Manmade troubles from other underground activities in the vicinity.

Unstable soil conditions.

Road rebuilds or relocations.

Future grade changes.

Unusual heavy traffic loading or the possibility of future heavy traffic loading.


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Except for isolated conduits that are placed in buried cable runs, new and rebuilt conduit

systems (main, lateral, subsidiary) must be concrete-encased. The concrete is nonstructural

concrete in accord with SAES-Q-001 and 09-SAMSS-0917. The encasement that is required

is the top and sides in all situations. The top, sides, and bottom are encased in unstable soil

situations. Telecommunication main conduit structures that are placed in roadways and other

traffic areas must provide a minimum ground cover (depth) of 760mm (30 in).

Additional protective measures (PVC-coated steel pipe or higher strength concrete for

encasement) are needed in situations where the conduit is placed in traffic areas at depths of

less than 760mm (30 in). Main conduit sections must be placed at a minimum depth (cover)

of not less than 610mm (24 in) under the following conditions, provided that heavy duty

power-activated equipment is not employed for backfill compaction:

Along streets/roads but outside the area that is reserved for present or future

traffic.

In other non-traffic areas and other areas that are not subject to heavy vehicular

traffic.

The color orange must be used to identify telecommunication facilities. This color

identification of telecommunication conduit systems is accomplished through the use of the

following methods:

Mix orange dye with the concrete (refer to SAES-Q-001).

Mix orange dye with the top layer of concrete (refer to SAES-Q-001).

Place orange marker tape above the conduit concrete encasement surface. The

marker tape is to be located 300 - 600mm below grade and approximately

300mm above the conduit system upper surface.


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Telecommunication cables or conduits must not be placed inside of the same concrete

encasement with power facilities or other underground utilities or facilities. Minimum

separation requirements between telecommunication facilities and non-

telecommunication/non-Saudi Aramco facilities must be maintained for identification,

protection from arcing, and reduction of stray currents. The minimum separation

requirements for telecommunication facilities are shown in Figure 2. These minimum

separation distances must be provided between telecommunication conduit structures and the

facilities that are listed in the figure.

Minimum Separation Requirements

Figure 2


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Standard Saudi Aramco duct formations that consist of four or more ducts must be two or four

ducts wide. Exceptions to this formation must be approved in writing by the Saudi Aramco

Communications Engineering Division, Outside Plant Unit. Main conduit formations may

have to be changed, in some situations, to clear obstructions. The duct formation must return

to the original (at exit of previous manhole) formation before the conduit enters the next

manhole in these situations. The minimum amount of concrete encasement that is used must

be 75mm (3 in) along the sides and top of the duct formation. The concrete must be a

minimum of 75mm (3 in) when the concrete is to be placed on the bottom of the conduits.

Curves or bends in conduit runs should be avoided except for the minor curves that are

involved when splaying conduits at manhole entrances. The curves or bends that are

necessary in main conduit sections must not transverse more than 90 degrees and must not

have a radius of less than 6 meters (20 ft). The permissible length of a conduit section that

contains a bend or curve depends upon the angle between the straight conduit run on each

side of the curve and the radius of the curve. Generally, main conduit section lengths orvarious degrees of curve and radii of curve should not exceed those angles and radii that are

indicated in the chart in Figure 3. Figure 3 shows the angle in degrees and the radius in feet

(meters).


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Conduit Lengths for Sections with One Curve

Figure 3


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Conduit offsets change the direction of a conduit run. Conduit offsets that are in main conduit

runs must be constructed with large radius sweeps with a minimum of 30 m (100 ft) radius.

This radius sweep will minimize the resistance that is offered by the sweeps when cable is

pulled in.

Conduit spacers that provide a minimum of 38mm (1.5 in) separation between ducts must be

used in all concrete-encased curved sections of 15 m (50 ft) or less. This construction and all

conduit encasements must comply with the requirements of the following standards:

SAES-Q-101 - Criteria or Design and Construction of Concrete Structures

O9-SAMSS-088 - Aggregates for Concrete

09-SAMSS-097 - Ready Mixed Portland Cement Concrete

Manholes

The standards to be used for manholes are GTE Section No. 622-500-100, SAES-T-911, and

standard drawing AA-036795. All manholes should be constructed to provide sufficient and

suitable space for the cables and associated equipment that will be installed. Manholes that

are near the central office must be designed to provide duct space for the ultimate size of the

central office. All manholes must be designed to the following requirements:

Support the heaviest anticipated traffic weight (see also GTE 622-500-100,

SAES-Q-006, and NESC).

Be reasonably waterproof.

Provide sufficient racking space for the ultimate number of cables and other

equipment that will be placed in the manhole.

The types and sizes of the manholes will be indicated on the work order detail plans. Smaller

size manholes may be precast or they may be the poured type of manhole. Manhole

construction must comply to the following standards:

SAES-Q-001 - Criteria for Design and Construction of Concrete Structures.

09-SAMSS-088 - Aggregates for Concrete.

09-SAMSS-097 - Ready Mixed Portland Cement Concrete.


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Types and Dimensions

Two types of manholes are available for use by Saudi Aramco:

Service manhole

Line manhole

Service manholes are designed for use as splicing or pulling points where no more than two

ducts (one duct for cable and one maintenance/repair duct) are located in the manhole. A line

manhole must be placed if more than two ducts are required. A service manhole must have

the minimum inside dimensions of 1.2m x 1.2m x 1.2m (4 feet x 4 feet x 4 feet) and must

permit cable racking on one wall only.

The line manhole is the basic manhole for telecommunications facilities. The dimensions of aline manhole are 3.75m x 1.85m x 2.0m (12 feet x 6 feet x 6.5 feet) (length x width x

headroom). This manhole can be a type A, J, L, or T manhole with the rearrangement of the

windows. The line manhole may contain a maximum of 24 main ducts in each end wall.

Line manholes must be designed for use in main and branch conduit systems when more than

two ducts will ultimately be required. If the number of loaded cable complements in the run

is insufficient to justify the construction of a loading manhole, this type of manhole may also

be used to house a minimum number of load coil cases. When the number and size of load

coil cases to be installed are small, load coils may be located in corners, attached to side

walls, or placed on the end walls of the manhole.

Laterals

A conduit and manhole system is only as good as the systems laterals that permit a readily

accessible network for distribution cables. When the laterals are built at the same time as the

main conduit, lateral ducts should be placed on top. This installation is not only the most

economical way to place the lateral duct, but it also affords some top protection for the main

run. Lateral ducts for future use should be placed at the same time as the main run. The only

additional cost that is involved is the cost of the material. This cost is negligible when

compared with the cost of the placement of a lateral system at a later date. Lateral ducts

between manholes that may be picked up and extended, when and where necessary, greatly

facilitate additions and changes in the distribution plant. Lateral ducts that are provided for

the future should be planned only after careful consideration of their future use. The length of

a lateral duct is limited mainly by the size of cable that will be pulled into the duct and by the

number of bends that the duct will contain.


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Termination

The termination of ducts that enter precast or poured-in-place manholes is greatly simplified

through the provision of duct terminators. The application of interlocking two- or four-way

duct terminator units replaces the individual end bells. The interlocking duct terminator maybe combined before the installation to accommodate variation in the number of duct

entrances. Watertight duct entrances through the concrete manhole wall are made easier

when plastic duct can be cemented to the ABS duct terminator. The duct terminators are

constructed of high-impact, virgin ABS, that is formed into a double wall design of one piece

in the following manner:

The terminators are positioned as shown in Figure 4 in the thin wall (web) of

the manhole.

Reinforcing rods are placed in the spaces between the duct terminator walls.

The spaces ensure proper flow of the concrete aggregate.

The shoulder is made deep enough to accommodate the wall of the type II duct.

The radii must permit a smooth bearing surface for conductors or cable in order

to eliminate the possibility of damage that can be caused by sharp edges.

Solvent cement is applied to the interlocking surfaces to achieve a watertight

seal.


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Duct Terminators

Figure 4


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Grounding

Manholes are grounded through the use of a ground electrode that provides a ground

resistance of 25 ohms or less and must be provided along with the necessary bonding ribbon

and wire in each manhole. A ground rod that is used as the electrode must be a minimum of5/8 inches in diameter by 10 feet in length. After the hole has been excavated, the ground rod

must be driven in the corner of the manhole floor approximately 100mm from the side and

end walls. A second ground rod that is needed to obtain the required minimum ground

resistance must be driven into the manhole corner diagonally opposite to the first ground rod.

Manhole excavation in rock or other high soil resistive areas requires that the manhole

electrode be provided in the following manner:

Place a bare #6 AWG (or larger) tinned solid copper wire grid or counterpoise

under the manhole floor. Access points must be provided through the use of an

extension that is a minimum of 2.5 m of #6 AWG (or larger) wire above themanhole floor in diagonally opposite corners. This location is where the

ground rods would have been placed.

Bore the rock to provide access for the standard (or larger) ground rods or for a

ground well.

Sump

A sump hole must be provided in the floor of all new manholes. The sump must be at least

205mm (8 inches) deep and either 205mm (8 inches) in diameter or 205mm (8 inches) square.

The sump hole must be centered under the manhole opening and at a depth so that the

finished surface of the manhole floor can be sloped toward the sump.

Pulling-In Irons

A minimum of one pulling-in iron must be set (cast in concrete) in the manhole wall opposite

all manhole conduit entrances (window). The pulling-in iron as shown in Figure 5 must

extend far enough into the manhole to provide a minimum clear opening of 75mm (3 inches).

The pulling-in irons are located 150-300mm (6-12 inches) below the conduits with which the

pulling-in irons are associated and in-line with the centerline of the conduits. Pulling-in irons

must not be placed closer than 150mm (6 inches) to any manhole entrance window. Pulling-

in irons must not be allowed to bear against the outside face of the manhole wall (come incontact with earth), but the pulling-in irons must have adequate cover of concrete in

accordance with SAES-Q-001.


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Pulling-In Irons

Figure 5


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Ladders

Hot dipped galvanized steel manhole ladders must be installed in all newly constructed

manholes, except the service manhole. A manhole step is to be set in the roof opening of all

manholes that have headroom depths greater than 2.75m (9 feet) in order to provide a supportfor the ladder. A manhole step must be placed in all manhole openings of a 405mm (16

inches) neck depth. An additional step must be laced for each additional 305mm (12 inches)

of neck depth.

Lids

Telecommunication manhole lids (covers) must be Type B with 30-inch frames and covers,

and the lids must have the identification mark TELEPHONE stamped in the cover to

indicate ownership. Type B frames and covers, as shown in Figure 6, have a nominal

opening diameter of 30 inches, an outside diameter of 31 3/4 inches, and weigh 320 pounds.

Type B frames have a base frame with an outside diameter of 49 inches, inside diameter of 41

inches, height of 10 inches, and weigh 440 pounds. The lids are constructed with

corrugations and reinforcing ribs.


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Lids

Figure 6


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Racks

Each telecommunication manhole is to be fully equipped with cable racks and rack supports

at the time of construction. Non-metallic concrete inserts must be placed in the walls to

provide a means for attachment of the ultimate number of cable rack supports, brackets andother surface-mounted equipment. Cable racks are to be spaced at a maximum distance

838mm (33 inches) and as illustrated in GTE section 622-500-100 manhole diagrams. The

distance from the inside surface of the manhole wall to the first cable rack must be 760mm

(30 inches) or less. The manhole interior configuration that is shown in Figure 7 is the

standard to be used for telecommunications manholes. Ducts and cable racks are located in

manholes. The number of ducts and cable racks will vary in accordance with the dimensions

of the manhole.


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Manhole Interior

Figure 7


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Pedestal Installations

Two basic types of pedestal installations are available for use by Saudi Aramco:

Pedestal/Terminal

Facility Area Connector

The pedestal/terminal type installation provides a location to splice cables and to terminate

service drops. The most widely used communication terminal by Saudi Aramco is a GHC-8

(SAMSS-18-021-375). This communication terminal is available from Utility Products.

The self-supported installation of a GHC-8 is shown in Figure 8. The pedestal is placed in

150mm of excavated earth and 370mm of undisturbed earth. These depths are measured from

the ground line to the bottom of the pedestal lower cover and the bottom of the pedestalbackplate. The width of the excavated earth is 305mm. A ground line marker is provided on

the pedestal. The pedestal is grounded through the use of a #6 AWG solid, bare, tinned

ground wire. The ground wire is bonded to a ground rod by means of an exothermic weld or

a ground rod clamp. This bond must be UL-listed for direct burial. The ground rod is placed

600mm from the pedestal and at a depth of 100mm from the ground line. The ground rod

must be a minimum 5/8 inch in diameter and 8 feet in length. The actual ground resistance of

the ground rod must be 25 ohms or less.


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GHC-8 (Self Supported Mounting)

Figure 8


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The GHC-8 can also be stake-mounted as shown in Figure 9. A stake is attached to the

pedestal. The pedestal is mounted in the earth in accord with the same mounting dimensions

and grounding requirements as the self-supported GH-8.

GHC-8 (Stake Mounting)

Figure 9


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The facility area connector (FAC) type installation provides an interface between feeder and

distribution cables. The most widely used communication FAC by Saudi Aramco is the

Feeder-Distribution Interface (FDI), 40EP-1-76S/1800 (SAMSS 18-013-165) from AT&T.

The AT&T Feeder-Distribution Interfaces are 40-type cabinets that are available with 76-type

binding posts. The FDI designation (40EP-1-76S/1800) describes the following construction

features:

40 - Cabinet type

E - Cabinet size

P - Pedestal mounting

1 - Splicing from front of cabinet

76 - 76-type binding post

S - Standard (feeder in or distribution)

1800 - Number of pairs

40-type (size E) pedestal cabinets have a width of 40 inches, a height of 54 inches, and a

depth of 12 inches. The construction of the pad foundation for an FDI can be referenced in

standard drawing AA-036389.

Direct Buried Cable

The following Saudi Aramco standards relate to buried cable installation:

SAES-T-629 - Buried Cable and Wire

SAES-T-928 - Buried Plant

SAES-T-629 modifies the GTE 629 series for Saudi Aramco outside plant applications. The

scope of this standard includes the requirements for the following topics:

General buried cable and wire requirements.

Buried cable and wire precautions.

Exchange buried cable, distribution and service wire placement.

Joint buried cable installation.

Optimize direct buried cable delivery system.

Guide-buried cable and wire installation.

Joint buried cable maintenance and emergency safety precautions.


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SAES-T-928 modifies the GTE 928 series for Saudi Aramco outside plant applications. The

scope of this standard includes the requirements for the following topics:

General buried plant requirements.

Housing terminal exchange buried plant - flush construction.

Housing terminal exchange buried plant - pedestal construction.

The minimum cover, fill material, and depth of excavation requirements are referenced in

standard drawing AA-036748. Standard drawing AA-036748 shows design requirements for

the following three installation situations:

Trenches in non-traffic areas

Trenches in rock

Trenches in Saudi Aramco road/street paved areas

The design requirements for trenches in non-traffic areas is shown in Figure 10. The cable is

placed at a minimum depth of 600mm. The cable must also be placed so that a minimum

space of 50mm exists on each side of the cable. The bottom of the trench is backfilled with a

minimum of 50mm of sand. The bottoms of excavated trenches and the backfill material for

use by Saudi Aramco must be free of rocks and debris that could damage the cables. The

cable is covered with a minimum of 50mm of sand or selected fill material. The next layer ofbackfill consists of 100mm of material that has no sharp rocks, no rocks that are larger than

50mm in diameter, and no organic material. The final layer of backfill consists of 450mm of

material that has no rocks that are larger than 100mm in diameter and no organic material

bulk. This 450mm layer also includes a buried cable marker tape that is placed at

approximately 50 percent of the cable depth, but not closer than 300mm to the cable. The

trench backfill must be compacted in 150mm lifts (200mm maximum) to the applicable

standard requirement. The compactness of non-traffic area trench backfill must be equal to or

better than the compactness of the surrounding material. Machine compaction is not

permitted within 150mm of the cable. The surface at grade level must be restored to as good

or better than original condition.


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Trenches in Non-Traffic Areas

Figure 10


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The design requirements for trenches in rock are shown in Figure 11. The maximum

excavation that is required in rock is 300mm. This maximum excavation assumes a minimum

cover of 200mm. The cable is placed at the minimum depth of 200mm. The cable is also

placed so that a minimum space of 50mm exists on each side of the cable. The bottom of the

trench is backfilled with a minimum of 50mm of sand. The cable is covered with 150mm of

sand or selected fill material. The buried cable marker tape is placed at approximately 50

percent of the cable depth. The final layer is 100mm of 3000 psi concrete. This layer of

concrete provides the required mechanical protection for the placement of buried telephone

cable with less than 450mm of cover.

Trenches in Rock

Figure 11


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The design requirements for trenches in Saudi Aramco road/street paved areas are shown in

Figure 12. The cable or conduit is placed at a minimum depth of 760mm. The cable or

conduit must also be placed so that there is a minimum space of 300mm on each side of the

cable or conduit. The bottom of the trench is backfilled with 50mm of sand or select fill

material. The cable is also covered with 150mm sand or selected fill material. The final layer

of backfill must be a minimum of 510mm of crushed aggregate or selected marl. This layer

of backfill must be placed in layers that are not more than 200mm. This method of backfill is

to achieve not less than a 95% density of the material. The

buried cable marker tape is located in this layer at a depth that is approximately 50 percent of

the cable depth but not closer than 300mm to the cable. The amount of roadway that must be

removed through the use of saw cuts must be 375mm back from the edge of the trench or half

the width of the trench, whichever distance is greater. The base of the roadway must be

primed, and the edges of the original pavement must be tacked. A minimum of 100mm (but

not less than the original) of pavement must be restored. This restoration consists of thefollowing two layers:

Bottom layer is a minimum of 50mm of a 4A bituminous mix.

Top layer is a minimum of 50mm of a 6A bituminous mix.


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Trenches in Saudi Aramco Road/Street Paved Areas

Figure 12


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Buried Service Wire

Buried service wire, as shown in Figure 13, is a shielded, double-jacketed, two-pair,

polyvinylchloride, insulated, conductor assembly that is designed for direct burial from a

buried cable terminal or equivalent point to the customers building structure. Four No. 20AWG (40 percent conductivity grade) copper-covered steel conductors are each insulated

with color-coded polyethylene compound and cabled into a star quad. The color codes are

red, green, black, and yellow. The red and green conductors are placed diagonally opposite to

each other and form pair one. The black and yellow conductors form the second pair.

The quad is enclosed in a polyvinylchloride jacket over which is applied 0.009-inch

ungalvanized, steel strips, in a helical serving with a flooding compound. A black

polyvinylchloride jacket is extruded over the entire assembly.

Buried Service Wire

Figure 13


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The following is a list of the minimum cover design requirements (per standard drawing AA-

036748) of buried service wire in various installation situations:

500mm in non-traffic areas

900mm under drainage ditches

200mm in rock locations

760mm under roads and streets

The design length of an individual buried service wire drop should not exceed 150m (500

feet). Buried service wire lengths up to 300m (1000 feet) are permitted on the occasions

where there is a legitimate reason for the placement of a longer drop. This longer drop length

must be included in the loop resistance/transmission calculations. Telecommunication cables

must be used when the drop length exceeds 300m.

Installing Cable Markers

The installation of cable markers above and below grade is required by Saudi Aramco. The

proper marking, identification, and placement of cable markers can prevent inadvertent

damage to the telecommunication cables.

Marking and Identification

Telecommunication buried cable runs are marked in accordance with the standard drawing

AB-036897. This drawing identifies two types of signs, as shown in Figure 14, a warning

sign (sign A) and a directional sign (sign B or C). The warning sign (480mm x 90mm)

identifies that an underground telephone cable run is present. The directional sign (90mm x

90mm) is an arrow that identifies the direction of the cable run. The lettering and arrows on

these signs are solid black in color on an orange background.


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Sign Types

Figure 14


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The sign post, which is shown in Figure 15, is 100mm x 100mm x 1.21m in size and is

constructed from redwood. The sign post is painted white in residential areas and orange in

field locations. The sign post is placed 450mm below the finished grade. The length of the

sign post that is above the finished grade is 760mm. The warning sign and directional sign

are mounted to the sign post.

Sign Post

Figure 15


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Underground cable runs and turns are marked as shown in Figure 16. A straight run as shown

in Figure 16 of underground cable is marked through the use of a sign post with a warning

sign (sign A) and a directional sign (sign B). Sign posts are placed in sufficient number, on

long straight runs of buried cable, to clearly indicate the route and to warn the public and

workmen of the cable. Sign post spacings are not to exceed 100 meters. The warning signs

and directional signs are attached to the sign posts and oriented so that the arrows point in

each direction along the cable run. A right angle turn, as shown in Figure 16, of underground

cable is marked through the use of a sign post with a warning sing (sign A) and two

directional signs (sign C). The sign post is placed at the intersection of the cable runs. The

two directional signs are oriented so that the arrows point each direction along the cable run.

An oblique turn of underground cable is marked similarly to a right angle turn through the use

of a marker post with a warning sign (sign A) and two directional signs (sign C). The major

difference in the way that an oblique turn is marked involves the marker post bevel details

that are required.


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Cable Runs and Turns

Figure 16


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Marker post bevel details (end view and front view) are shown in Figure 17. The top of the

marker post is trimmed at the necessary angle to align the directional sign (sign C) arrow with

the cable.

Bevel Details

Figure 17


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Placement in Trenches

Buried cable marker tape (18-079-890) is required to be placed in trenches at approximately

50 percent of the cable depth. The marker tape must not be placed closer than 300mm to the

cable.

Separation

The separation requirements for telecommunication conductors can be referenced in the

following Saudi Aramco Engineering Standards:

SAES-T-629 - Buried Cable and Wire

SAES-T-911 - Telecommunication Conduit System Design

SAES-T-928 - Buried Plant

Telecommunication cables can be placed in trenches by means of one of two methods. These

two methods are the random separation method and the fixed separation method. At Saudi

Aramco, telecommunication cables and power cables are not permitted to be direct buried

together in the same trench by the random separation method. The random separation method

that is shown in Figure 18 places the communication facilities (telephone) and other utilities

(CATV, secondary supply, gas, and primary supply) in the trench without any specific

separation distances. The minimum cover is 18 inches.


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Random Separation

Figure 18


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The fixed separation method as shown in Figure 19 requires that specific distances be

maintained between communication facilities (telephone cable) and other utilities (power

cable). The bottom of the trench is covered with 50mm of sand. The preferred distance

between the power cable and telephone cable is 1m or more in a joint trench. The distance

must not be less than 300mm of well tamped earth. The cables must be located a minimum of

50mm from the trench wall. The minimum cover that is required for the cables is 600mm.

Fixed Separation (Joint Trench Only)

Figure 19


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The separation of telephone cables and power cables at crossovers can be accomplished

through the use of earth separation or concrete separation. Earth separation as shown in

Figure 20 requires a minimum vertical separation of at least 300mm of well tamped earth

between the power cable in the power trench and the telephone cable in the telephone trench.

If the power cable voltage exceeds 15kV phase-to-phase (8.7 kV phase-to-ground), the

telephone cable must be placed inside conduit at the crossover.

Crossover (Earth Separation)

Figure 20


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Concrete separation as shown in Figure 21 requires a minimum vertical separation of at least

75mm of concrete between the power cable in the power trench and the telephone cable in the

telephone trench. The concrete slab must be a minimum of 100mm in width. The concrete

slab must also extend at least 300mm from the nearest point of the telephone cable to the edge

of the concrete.

Crossover (Concrete Separation)Figure 21


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SPLICING CABLE: METHODS, MATERIALS, AND NUMBERING CODES

This section deals with the joining of multipair communication cable (and associated work) in

unclassified areas. The American Petroleum Institute (API) practices RP-500, A, B, and C

and the National Electrical Code (NEC) should be referenced for installations that are within

electrically classified (hazardous) areas, as defined by SAES-B-068. This section will cover

the following information:

Cable Numbering and Count Identification

Methods

Materials

Cable Numbering and Count Identification

Splicing operations are necessary to join cable conductors together. It is rare when an

individual cable will reach between the two desired locations. Splicing is the joining of two

or more cables together by splicing the conductors pair-for-pair and then covering the opening

with a water-tight case. In order to maintain correct polarity for the circuit when individual

cable pairs are being spliced together, it is necessary to splice the tip conductor of one cable to

the tip conductor of the other cable and to splice the ring conductor of one cable to the ring

conductor of the other conductor. At Saudi Aramco, splicing is normally referred to as color-

to-color throughout the cable within the correct binder group.

Splicing operations are necessary to complete cable transfers. The transfer of a working line

from one cable pair to another cable pair requires a change of the cross connection at the main

frame or rearrangement at a cross-connect terminal. Sectional transfers of cable pairs from

one cable to another cable where the pair count of the old and the new cable remain the same

may be done on a pair-for-pair basis. Cable numbering and count identification minimize the

chance of error during a cable transfer. Cable pairs that are energized are identified by

numerical designations, and dead pairs are identified by alphabetical designations. Cable

designations, as shown in Figure 22, are located on construction drawings and include the

following parts:

Cable Type Designation

Cable Number Designation

Dear Pair Designation


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The cable type designation identifies the cable type, construction, number of pairs, and wire

gauge. The cable number designation consists of a numerical designation and the applicable

pair count. The dead pair designation consists of an alphabetical designation and the

applicable pair count. The splicer, engineer, and OSP records will treat this alphabetical

designation the same as if the alphabetical designation were a cable number. The dead pairs

in a cable will be shown in the exact order that the dead pairs appear in the cable.

A cable number designation, cable count, is an identification that is used as a common

designation throughout the length of a transmission circuit in a multi-circuit cable facility. It

usually originates in the Central Office Main Distribution Frame (MDF).

Sheath count is another important designation. The sheath count of a cable is the physical

identification of individual pairs of conductors in a piece of multi-pair cable. Physical

location of the cable count in the sheath count can be made by counting through a standard

PIC coding scheme, which is used to identify individual pairs of conductors or groups of pairs(binder group).

Cable Designation

Figure 22


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The splice through example in Figure 23 shows that the cable A 101-200 is spliced through

the intermediate splice. The non-splice through example that is also shown in Figure 23

shows that the cable A 101-200 is not spliced through the intermediate splice.

Cable Count (Splice Through)

Figure 23


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Cable count changes or transfers are also shown on construction drawings. A cable transfer

fill box as shown in Figure 24 provides the following information:

Splice Sequence No. (number) or Work Location No.

Number of PR (pairs) Transferred

Number of PR (pairs) Working

The cable transfer fill box at work location 2 indicates that 100 pairs are transferred and 21

pairs are working. The transfer or count change of a cable can also be indicated through the

use of parentheses.

A count change through the use of parentheses is also shown in Figure 24. The U600-24P

cable runs between manhole (MH) #3139A and MH #3139. This cable contains cable 14,1501-1800+, and cable 9, 1501-1800, and it has no count change. The U600-24P cable is

spliced to U900-24P and U100-22P in MH #3139. The original count of U900-24P consisted

of the following cables:

14, 1501-1800+

A, 301-500+

3, 201-300+

9, 1701-1750+

A 651-900

The new count for U900-24P changed to the following cables:

14, 1501-1700+

A, 201-600+

9, 1701-1750+

A, 651-900


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The count change resulted in the removal of cable 3, 201-300+, and the decrease of 100 pairs

to cable 14, 1501-1800+. In the case of U100-22P, the cable 3, 201-300, was changed with

cable 9, 1526-160+, and A 76-100.

The use of parentheses for cable count changes should not be confused with the use of

parentheses to indicate the removal of cable. A cable removal example is also shown in

Figure 24. The cable UF 300-24P that is located in MH #3139 is indicated to be removed.

Cable Count Change (Transfer)

Figure 24


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Methods

All Saudi Aramco cables are even count color coded plastic insulation cables (PIC). Standard

binder group to binder group, color to color splicing is the only type of splicing that is used by

Saudi Aramco.

This section covers the following methods for copper cable splicing:

Straight Splices

Butt Splices


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Straight Splices

Telecommunication cable of the same size can be joined through the use of a straight splice.

A straight splice joins like-color binder groups only, and the cable pairs are joined color to

color. All binder groups are marked at both ends of the straight splice. The straight splice asshown in Figure 25 joins, by means of a connector, the matching cable pair conductors (ring

to ring and tip to tip) from one cable to another cable to form a complete circuit. The cable

pair conductor must be seated firmly against the stop to ensure a satisfactory electrical

connection.

Straight Splice

Figure 25


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Butt Splices

Bridge and tap connections can be accomplished through the use of butt splices. The bridge

connection joins three or more cable pair conductors (ring-to-ring or tip-to-tip) to form a

parallel circuit. The bridge connection, or half tap connection, as shown in Figure 26 joins

three cable pair conductors through the use of a connector. The cable pair conductors must be

set firmly against the stop to ensure a satisfactory electrical connection. The connectors are

bundled in place with a cable tie in a completed connection.

Half Tap Connection

Figure 26


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The tap connection joins an additional cable pair conductor to a circuit to form a branch

circuit. The tap connection as shown in Figure 27 joins the cable pair conductor of a through

circuit to the cable pair conductor of a branch circuit through the use of a connector. The

cable pair conductors complete the electrical circuit through a contact that is inside the

connector.

Tap Connection

Figure 27


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Materials

This section will cover the following splice devices and materials that can be specified for a

particular job:

Splice Closures

Connectors/Bonding Clips

Splice Closures

The purpose of splice closures is to protect joined (spliced) cable pairs. Splice closures can

be applied in manhole and buried cable installations.

The following splice closures are available for use in manhole installations:

Preformed SS splice closure

REDDI seal

The following splice closures are available for use in buried cable installations:

REDDI seals

Better buried splice closure

Connectors/Bonding Clips

The following list of splicing materials/connectors as shown in Figure 28, are the most widely

used for splicing polyethylene conductors:

UR 18-021-952 (3M Scotchlok)

UG 18-021-953 (3M Scotchlok)

PICA Bond 18-022-018 (Amphenol)

The UR and UG connectors consist of a transparent thermoplastic base with a red or green

plastic button in an orifice at the top of the base. Metal inserts are molded into the plastic

button. These inserts have sawtooth edges that puncture the cable insulation and make

electrical contact with the conductors when the button is fully compressed. The UR

connectors are filled with silicone grease. This grease serves as a moisture barrier for the

connection. The UR connector can be used to insulate, butt splice, and seal any two or three


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19, 22, 24, or 26 gauge cable conductors. The UR connector can be used with 19 gauge filled

conductor. The UG connector can be used for tap splices.

The Picabond or AMP connector is smaller than the Scotchlok connectors. The use of a

Picabond connector results in a much smaller splice bundle. This smaller splice bundle is

very desirable in high pair count cables. The Picabond connector is available with sealant for

through and bridge connections in a butt splice configuration. Each Picabond connector as

shown in Figure 28 consists of a preassembled two-piece housing (contact retainer housing

and wire entry housing) and an insulation displacement contact. This contact will accept solid

copper conductors in any combination of 19 through 26 AWG in the conductor holes This

conductor is crimped with a standard crimping tool.


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Connectors

Figure 28

Bonding clips are provided to permit reliable electrical connections to the aluminum shield for

noise-shielding purposes and for maintenance of electrical continuity. The use of bonding

clips is specified by a particular splice closure. Scotchlok brand 4460-S shield connectors

(18-021-980) are available for use by Saudi Aramco to bond cable to other ground systems.

Scotchlok brand 4460-S shield connectors require standard hand tools to form a bullet bond.


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BURIED CABLE: SPLICING, BONDING, AND SEPARATION REQUIREMENTS

All cables for direct burial must be thoroughly inspected before, during, and after installation

(before back filling trench) to determine that the cable is placed without damage to sheath,

shield, or conductors. These inspections are necessary because location and repair are much

more difficult after installation.

With respect to buried cable, this section will cover requirements for the following:

Splicing

Bonding and Grounding

Separation

Splicing

This section describes splicing design considerations for the following applications:

Direct Buried

In Pedestal

Direct Buried

All direct buried cable splices must be filled with a reenterable encapsulating compound onair core as well as filled cables. The splice closure that is used must be a type that is

manufactured and designed to hold the encapsulating compound. The pressure wrap kit, or a

similar product that utilizes a perforated web liner, must be used in all encapsulated

reenterable splice closures. Saudi Aramco communications personnel do not normally

directly bury splices. The splices are placed inside pedestals such as the GHC-8.

Saudi Aramco has approved for use the following types of splice closures:

REDDI Seal Cable Closure (Preformed Line Products)

Better Buried Closure (3M)

The REDDI seal cable closure that is manufactured by Preformed Line Products is the most

widely used splice closure in Saudi Aramco for buried cable splices. This splice closure is

designed to be filled with a reenterable encapsulating compound. This compound protects the

splice bundle from the surrounding environment. The REDDI Seal Cable Closures are

available in three different diameters, 4 in (10.16 cm), 6 1/2 in (16.51 cm) and 9 1/2 in (24.13

cm).


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The 3M Companys RJ Series Better Buried Closure System (material that is available from a

local vendor) provides acceptable closures for this purpose. This closure comes in different

series and sizes that will accommodate cables with outside diameters that range from 25mm to

101mm. A support assembly will be used with 125mm and larger diameter-filled closures

that are installed in manholes.

The 3M Better Buried Closure Body Sleeve Halves and End Caps are designed and made of

material that withstands acids, detergents, chemicals, and other harmful elements to ensure

direct buried splice integrity. The Better Buried Closures are available as complete closure

kits, component kits or as individual parts to meet specific application requirements for direct

buried straight and butt splices, cable repair, and other direct buried applications such as tap

splicing and sheath repairs.

In Pedestal

Conductor splices and terminations are to be made in accordance with the appropriate sectionof SAES-T-632. Upon completion of the splice, the two conductor groups should be

physically and electrically isolated from each other and the pedestal.


The shield of all cables will be bonded together electrically with the use of bonding clips.

Bonding clips should be applied as required to obtain shield continuity of the cables.

A ground wire clamp is attached to each bonding clip, as shown in Figure 29. The ground

wires are bonded through use of a ground wire connector. An additional ground wire is used

to bond the entire assembly to a ground rod. The resistance of the ground rod must be lessthan 25 ohms. Below ground connections between the ground rod and ground wire is

achieved through the use of a cadweld bond.


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Figure 29


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Separation

The separation of buried cables is required for identification, protection from arcing, and the

reduction of stray currents that result from the cathodic protection on pipelines. Detailed

drawings that show separation distances are shown in the civil work for structures in this

Module. These drawings can also be referenced in standard drawing AA-036748. The

minimum separation chart that is shown in Figure 30 summarizes the minimum separation

distances between buried telephone cable and various utilities (buried power, water, gas,

sewer lines, buried CATV, instrumentation cables, and oil field pipelines).

Minimum Separation Chart

Figure 30


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TECHNIQUES AND DESIGN CONSIDERATIONS FOR PULLING, RACKING,

SPLICING, AND BONDING AND GROUNDING OF UNDERGROUND CABLE

In regard to underground cables this section will cover techniques and design considerations

for the following:

Pulling

Racking

Safety

Splice Closures


Pulling

Cable pulling is the operation that places underground copper cables in conduits that are

between manholes. Cable pulling operations can also remove telecommunication cables from

conduits that are between manholes.


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Standards

The following is a list of the Saudi Aramco Engineering Standards that apply to cable pulling:

SAES-T-628 Underground Cable

This standard describes the mandatory requirements that govern the design

and installation of telecommunications underground cables. The scope of

this standard includes the following topics:

- Installation of Rodding Ducts and the Placement of Pull Line (Rope)

Underground Cable

- The Installation and Removal of Underground Cable and Rubber

Conduit Plugs

- The Description and Use of Cable Underground Conduit Sealing Kit

PR-851

- Installation Precautions for Underground Cable

- Procedures for Open Flames in Manholes

- The Testing and Ventilating Procedures for Underground Manholes

and Cable Vaults

- The Placement of Underground Cable in Main Conduit

- The Installation of Cable Guards at Riser Poles and Buildings

- The Placement of Underground Cable in Subsidiary Conduit

- Splicing Arrangements in Manholes

- The Placement of Underground Cable Loading Coil Cases

- The Removal of Underground Cable

- The Placement and Splicing of Bonded ASP Cable


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SAES-T-911 Telecommunication Conduit System Design

This standard describes the mandatory requirements that govern the design and installation of

telecommunications conduit and manhole systems. The scope of this standard includes the

following topics:

- General Considerations for Conduit

- Manhole Design

- Underground Conduit Materials

- Inspection, Information for Concrete, Mortar, and Reinforced

Concrete

- Conduit Design and Layout

- Conduit Design of Formations

- Engineering Considerations for Long Pulls of Underground Cable

- Underground Entrances to Central Office Buildings

- Conduit Duct Selection and Cable Measurement


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Procedures

Underground cable pulls must be based on joint engineering and construction evaluations.

These evaluations consider theoretical, practical, and job experience factors. Cable pull

calculations must be included in the design package. Cable pulling procedures must take thefollowing factors into consideration:

Tension Limitations

Total Pull Length

Cable Reel Setup Location

Cable Pull Direction

Cable Pull Locations

There is a limit to the amount of tension that can be used to pull cables into a length of

conduit. Pulling tension is determined by the weight of the cable, the coefficient of friction of

the conduit, and the geometry of the duct run. Cable tension calculation can be done through

use of the tension formula in SAES-T-911, section 4.7.5, page 52 or through use of the CSD

computer program.

In newer duct installations, the manhole intervals can be as high as 1000 feet because cables

are now manufactured in longer lengths. Also the lighter weight, composite sheaths make the

pulling of the longer lengths much easier.

The duct should be checked for obstructions such as misaligned conduit or collections of silt.

This check is made by rodding. The rods are short enough to fit into a manhole and are

threaded on both ends. One section of the rod is pushed into the duct and another section is

screwed on. This operation is continued until the advance rod enters the next manhole.

Usually, a pulling line is attached to the end, and the rods are removed section by section.

The duct then is cleaned. Mandrel tests are required as directed by SAES-T-628, 4.1.3.

A reel of cable is positioned at one manhole in order to pull the cable into a duct. The reel of

cable must be able to rotate. A winch is located in the next manhole. The winch line is pulled

through the duct with the attached cable.

Prior to a cable pull operation, all equipment should be checked to make sure the equipment is

properly positioned. Prior to the start of the operation, the type and use of signals should also

be discussed and thoroughly understood by the personnel who are involved in the operation.


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The first 20 feet of the cable should be generously lubricated to reduce initial duct friction.

The amount of the lubricant that is required during the remainder of the pull should be

determined by the conditions that are encountered. Conditions such as bends, long pulls, or

pulls through manholes may require more lubricant. Only lubricants specifically approved by

Saudi Aramco may be used.

The cable as shown in Figure 31 must be pulled slowly until at lest two feet of cable has

entered the duct. This length (two feet) may be determined by the measurement of the

distance from the top of the cable feeder to the duct entrance, plus two feet. An equal

distance should then be measured from the end of the cable and marked with vinyl tape. The

cable is pulled slowly until the tape marking reaches the funnel of the cable feeder. The

required two feet of cable are in the duct when the tape marking reaches the funnel. From this

point, the cable may be pulled, steadily and continuously, at a rate of 80 to 100 feet per

minute.

The cable pulling speed should be reduced when the cable has been pulled to within 20 feet of

the manhole. This distance (20 feet) is determined by the quantity of cable that remains on

the reel. The cable should be pulled at the reduced speed until the swivel link is 6 inches from

the sheave that is located in the manhole.

The tension on the winchline should be maintained if the cable pull is stopped because of reel

trouble or other reasons unless the operator is asked to release the line tension. The pulling

speed should be increased gradually until the cable moves freely when the cable pull is

resumed.

An approved luffing grip as shown in Figure 31 should be used to pull the additional specifiedquantity of cable into the manhole. A luffing grip differs from ordinary cable grips in that the

luffing grip is equipped with an offset eye that permits the grip to be placed on the cable at

locations other than the end. Split cable grips, nylon slings, and frayed rope slings may be

used as luffing grips.


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Cable Pulling

Figure 31


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Racking

Cable racking design for copper cables must consider the following factors:

To minimize the changes in cable level.

To determine that the racking of a given cable in the proposed manner will not

block or restrict the use of any vacant duct or racking position.

To make the radius of a cable bend as large as possible (the radius of the bend

must be a minimum of 10 times the diameter of the cable).

Standards

The following is a list of the Saudi Aramco Engineering Standards that apply to cable racking:

SAES-T-628 - Underground Cable

SAES-T-911 - Telecommunication Conduit System Design

Procedures

The following racking space requirements as shown in Figure 32 must be maintained for

copper cable in manholes:

For racking stub and lateral cables, a minimum space of 385mm (15 in) must

be maintained in all manholes between the roof of the manhole and the center

of the top main cable.

A minimum space of 385mm (15 in) must be maintained between the manhole

floor and the center of the bottom main cable.

A minimum vertical space of 195mm (7.5 in) for staggered splices and 230mm

(9 in) for non-staggered splices.


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Racking Space

Figure 32


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The cable racking requirements for a total of six to twelve main ducts that enter on each end

wall must provide for double bay, single cable racking on each side wall.

The cable racking requirements for a total of fourteen to twenty four main ducts entering on

each end wall must provide for double bay, double cable racking on each side wall.

The Saudi Aramco procedures for duct assignments is that cables be assigned to bottom ducts

first, for the following reasons:

Cable splicers will not have to work underneath cables that are placed at higher

levels.

In the event that damage is done to the conduit system, the empty top ducts

would probably be damaged first. The lower ducts would remain protected.

Ducts should be selected to avoid the following situations:

Cable crossovers between the duct entrance and the cable rack.

Blockage of future access to vacant ducts.

Racking arrangement and order of duct selection for a line manhole are shown in Figure 33.

The duct numbers indicate the order of assignment selection. Single cable racking is shown

on the 2-wide duct configurations. Double cable racking is shown on the 4-wide duct

configurations.


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Single and Double Cable Racking

Figure 33

The numerical order of duct selection that is shown in Figure 33 should not be confused with

the numerical designation of ducts. Ducts are designated by numbers in accordance with


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SAES-T-911, section 4.9.24. Duct numbers are designated left to right, bottom to top, and

start with the bottom left side duct. (This view faces away from the central office).


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Hardware Requirements

All manhole hardware must be of the non-corrosive type such as hot dipped galvanized or

better. The requirements for the racking of copper cable can vary with the type of manhole.

The basic telecommunications manhole can have a maximum of 24 main ducts in eachendwall.

Cables and completed splices that are located in manholes should be supported with cable

hooks. Cable hooks are available in several sizes (4 in, 7 1/2 in, 10 in, and 14 in). The cable

hook as shown in Figure 34 has a tab that can be inserted into the cable rack upright. Cable

rack hook positions in all manholes are numbered from the top down to the bottom of the

uprights. The slots in the cable hook permit the cable to be secured to the cable hook through

the use of a lashed cable support.

The hardware requirement for situations where the distance between the cable racks is such

that the weight of splice closure results in cable sag, the splice closure should be secured to apiece of pipe or other support material. This support material is laid across the cable hooks.

The splice closure is secured tightly to the pipe with lashed cable supports.


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Cable Hooks

Figure 34


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Safety

Cable pulling and racking operations require manhole entry and specific safety precautions as

a result of the following contaminants that can be present in manholes:

Vapors or gases that have escaped from underground storage or from the

piping of liquids or gases such as gasoline, natural gas, liquified petroleum gas,

propane, and butane.

Gases from fermentation of naturally occurring organic matter such as

methane, carbon dioxide, and hydrogen sulfide.

Gases such as carbon dioxide or carbon monoxide that are created as by-

product of combustion (from vehicles or equipment).

Manhole pre-entry combustible gas tests are made to ensure that there is no risk of explosionwhile, or immediately after, the removal of the manhole cover. Continuous forced ventilation

ensures an adequate oxygen supply and prevents possible build-up of combustible/toxic gases

or vapors. Periodic combustible gas tests provide an additional margin of safety that ensures

that no combustible gas is building up in the manhole. The Work Permit Systems in G.I.

2.100 and Gas Testing Procedures in G.I. 2.708 must be referenced when atmospheres that

exceed 60 percent of the Lower Explosive Limit (LEL) are detected in the manhole.

Splicing

The design requirements for the placement of splice closures vary with the number of ducts

and the length of the manhole. Splice closures can be placed in non-staggered and staggeredarrangements. Staggered splices are employed in those manholes where there are a large

number of entering ducts and where the length of the manhole is sufficient to place three

cable racks.


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The design requirements for the splicing of underground cable require the use of the

following splice closures:

Preformed stainless steel splice closures

REDDI seal cable closure

The preformed stainless steel (SS) splice closure is designed to hold air pressure. An

encapsulating compound is not placed in SS splice closures. The SS splice closures are

preferred for manhole splices. The SS splice closures should be installed between the

manhole racks. The SS splice closures are designed for numerous re-entries.

The Reddi Seal Cable Closure is manufactured by Preformed Line Products (PLP) for use on

filled cable in underground and buried plant splices. This closure must be filled with a

reenterable encapsulating compound whether the closure is used on filled or air core typecables or whether the spliced cables are buried or underground. This closure will not hold air

pressure, and Reddi Seal end plates are not interchangeable with the pressurized preformed

splice case.

These closures are available in many sizes, as shown in Figure 35. The table shows

maximum end plate cable capacity for several cables (1, 2, 3, and 4 cables) and each of the

splice closures.


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Splice Closure Data

Figure 35


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In underground cables, as shown in Figure 36, shield and armors, if present, should be bonded

together in each manhole and/or pedestal. The metallic shields, including any armor of all

cables through splices, splice cases, terminals, apparatus, cabinets, etc., must be continuous

throughout the length of the cable, except where the cable is purposely broken by an

insulating joint. All bonds are to be connected to a common ground to ensure that all cables

are at the same potential after all the metallic shield and armor of the cables are made

continuous with a bonding wire.

Underground Bonding and Grounding

Figure 36


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GLOSSARY

Bonding A low-impedance path that is obtained by permanently jointing all

noncurrent-carrying metal parts to ensure electrical continuity and

that has the capacity to safely conduct any current that is likely to be

imposed on it.

Bundle Several individual fibers that are contained within a single jacket or

buffer tube. Also, a group of buffered fibers that are distinguished

in some fashion from another group in the same cable core.

Buried cable A cable that is installed under the surface of the ground in such a

manner that it cannot be removed without disturbance to the soil.

Also referred to as direct-buried cable.

Cable An assembly of one or more conductors or optical fibers that are

placed within an enveloping sheath and that are constructed to

permit use of the conductors singly or in groups (FED-STD-1037A).

Cable Rack The vertical or horizontal open support (usually made of hot dipped

galvanized steel) that is attached to a ceiling or wall.

Conduit A rigid or flexible metallic or nonmetallic raceway of circular cross

section through which cables can be pulled or in which cables can

be housed.

Pull Cord/Pull Wire Cord or wire that is placed within a raceway and that is used to pull

wire and cable through the raceway.

Splice Closure A container that is used to protect joined (spliced) cable pairs.

Trench A narrow furrow dug into the earth for the direct installation of

buried cable or for the installation of underground cable within

troughs or ducts.

Underground Cable A telecommunications cable installed under the surface of the earth

construction requirements for communication installations

Documents