es-14-603-05

Pressure Relieving Devices - Management and Maintenance ES-14-603-05

Version No. 4.0 Page 1 of 12

Document last modified: 16 January 2013. Date printed: 18 January 2013.

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Title: PRESSURE RELIEVING DEVICES - MANAGEMENT AND MAINTENANCE

Number: ES-14-603-05

Version Number: 4.0

Date Revised: 16 January 2013

Owner: Ron Caporn

Authoriser: Manoj Thakur

Reasons for Creating or Amending Document

Full Review of Document

Actual Change Details: New Authoriser - Manoj Thakur Control Block upadated

TABLE OF CONTENTS 1. SCOPE ....................................................................................................................................... 3

2. PURPOSE .................................................................................................................................. 3

3. DEFINITION OF TERMS ....................................................................................................... 3 3.1 PRESSURE RELIEVING DEVICE ...................................................................................... 3 3.2 MAXIMUM ALLOWABLE WORKING PRESSURE ........................................................ 3 3.3 BACK PRESSURE ............................................................................................................... 3 3.4 COLD SET PRESSURE ....................................................................................................... 3 3.5 COMPETENT PERSON ....................................................................................................... 4

4. STANDARDS ............................................................................................................................ 4

5. RELIEF VALVE DESIGN CRITERIA .................................................................................. 5 5.1 GENERAL ............................................................................................................................ 5 5.2 EFFECTS OF BACKPRESSURE ......................................................................................... 5 5.3 OVERPRESSURE ................................................................................................................ 5 5.4 CALCULATIONS ................................................................................................................ 6

6. GASKETS .................................................................................................................................. 6

7. PAINTING ................................................................................................................................. 7




8. IDENTIFICATION ................................................................................................................... 7

9. DOCUMENTATION ................................................................................................................ 7 9.1 TECHNICAL DATA SHEET ............................................................................................... 7 9.2 TEST CERTIFICATE ........................................................................................................... 8 9.3 SAFETY RELIEF VALVE INSPECTION & REPAIR DOCUMENT ................................ 8 9.4 J D EDWARDS COMPUTER SYSTEM (JDE) ................................................................... 8 9.5 WORK ORDER HISTORY .................................................................................................. 8

10. INSPECTION AND TESTING ................................................................................................ 9 10.1 NEW PRESSURE RELIEVING DEVICES ......................................................................... 9 10.2 IN-SERVICE PRESSURE RELIEVING DEVICES ............................................................ 9 10.3 RE-TESTING OF RELIEF VALVES ................................................................................. 10 10.4 ON-STREAM INSPECTION AND TESTING OF RELIEF VALVES ............................. 11

11. INSPECTION OF BURSTING DISCS ................................................................................. 11

12. PACKAGING, TRANSPORTATION AND STORAGE .................................................... 11




1. SCOPE

This document defines the minimum requirements for the selection, installation, inspection, testing, commissioning, and maintenance of Pressure Relieving Devices.

2. PURPOSE

To ensure that all pressure systems are protected by the use of Pressure Relieving Devices (PRDs), and that they are subject to a regular inspection, testing and maintenance programme.

3. DEFINITION OF TERMS

3.1 PRESSURE RELIEVING DEVICE

A Pressure Relieving Device is a device that protects equipment from internal or external overpressure conditions. For example:

Pressure Safety Valve (PSV); Relief Valve (referred to as PSV in the JDE System and this document); Vacuum Breaker (referred to as PSV in the JDE System and this document); Thermal Relief Valve (referred to as PSV in the JDE System and this document); Hydrostatic Relief Valve (HRV), and Bursting Disc.

Note: Pressure Control Valves, buckling pins, and other similar items are not part of this Standard.

3.2 MAXIMUM ALLOWABLE WORKING PRESSURE

The Maximum Allowable Working Pressure is the maximum pressure that the system, vessel, or pipeline is allowed to operate under normal service conditions, in accordance with the applicable design code for the system.

3.3 BACK PRESSURE

Backpressure is the pressure that exists at the outlet of the valve as a result of pressure in the discharge system configuration (e.g. discharge to common flare header).

3.4 COLD SET PRESSURE

Cold Set Pressure is the pressure that the valve is set to relieve at on the test-rig. The set pressure compensates for operating conditions of temperature and backpressure.

Note: The valve manufacturers recommendations for cold set pressure shall be followed for valves operating above or below atmospheric temperature.




3.5 COMPETENT PERSON

Is one who has through a combination of training, education and experience acquired knowledge and skills to enable that person to perform a specific task correctly.

4. STANDARDS

CSBP Engineering Standards ES-14-101-06 Equipment Numbering System ES-14-101-12 Technical Data Sheets - Mechanical, Electrical, & Instrument ES-14-102-12 Protective Coatings ES-14-601-01 Basis for Design Piping ES-14-603-01 Piping Material Specifications

CSBP Guide Manuals GM-05-043-01 Guide Manual for Technical Data requirements for Plant and Equipment GM-05-090-01 Plant Inspection Management

CSBP Forms IF 1486 Technical Data Sheet: Valve Safety Relief SF2123 PSV On-Stream Visual Inspection Report

Australian Standards AS 1210 Pressure Vessels AS 1271 Safety Valves, Other Valves, Liquid Level Gauges and Other Fittings for

Boilers and Unfired Pressure Vessels AS 3788 Pressure Equipment - In-Service Inspection

American Petroleum Institute API RP 520 Sizing, Selection and Installation of Pressure-Relieving Devices in

Refineries API RP 521 Guide Manual for Pressure-relieving and Depressuring Systems API RP 576 Inspection of Pressure Relieving Devices API STD 527 Seat Tightness of Pressure Relieving Devices American Society of Mechanical Engineers

ASME Boiler and Pressure Vessel Code Section VIII Pressure Vessels, Divisions 1 and 2

Underwriters Laboratories Incorporated UL 132 Safety Relief Valves for Anhydrous Ammonia and LP-Gas




5. RELIEF VALVE DESIGN CRITERIA

5.1 GENERAL

Inlet and discharge piping shall comply with CSBP Engineering Standards: Basis for Design Piping (ES-14-601-01) and Piping Material Specifications (ES-14-603-01), and any specific installation requirements of the Manufacturer and the applicable valve code.

Valves protecting pressure vessels shall comply with AS 1271 or equivalent standard.

Pressurised ammonia storage and transport vessels may use pop-action soft-seated valves that are compliant with UL 132.

Valves protecting piping and instruments shall comply with either:

AS 1271, ASME VIII, API RP 520, UL 132, or Vendor standard (to be approved by Responsible Officer) e.g. Swagelock CPA series valves for

hydrostatic relief duty.

Valve shall have a body drain and spring chamber vent fitted as per the Manufacturers recommendation. Drains and vents are to discharge away from personnel.

Valve shall have a weather cover fitted if it is of the exposed spring type, and shall have its body insulated if recommended by the Manufacturer (e.g. Steam safety relief valves).

5.2 EFFECTS OF BACKPRESSURE

The effects of backpressure shall be considered in valve selection, in particular:

Pressure rating of outlet side of relief valve. Valve type (balanced or conventional). Valve capacity. Cold set pressure (permanent backpressure). Backpressure leak test (total backpressure).

5.3 OVERPRESSURE

Possible causes of overpressure shall be examined to determine relief cases applicable to each valve. As a minimum, the following should be considered:

Fire Tube failure Thermal expansion Blocked discharge Control valve failure/malfunction Control valve bypass operation




Valve malfunction Coolant failure Power failure Instrument air failure Other utility failures Pump/fan/compressor failures Chemical reactions Excessive heat input Any special circumstances for particular applications.

5.4 CALCULATIONS

Calculations and / or notes determining the relief valve governing sizing case and the required capacity shall be produced. Where more than one relief case is applicable to an application (e.g. fire and burst tube), calculations and / or notes shall be provided for all cases.

Calculations of selected valve capacity under relieving conditions shall be produced to prove adequacy of the valve sizing.

The standards and any assumptions used for capacity calculations, both required and actual, shall be stated in the calculations and notes. Fire and tube rupture calculations shall be in accordance with pressure vessel codes. For other cases API RP521 can be used as a guide.

Calculations and / or notes shall be made to ensure pressure drops in and out of relief valves do not:

exceed the maximum allowed for the valve by the manufacturer; reduce the capacity of the valve below that required; impact on the type of valve used.

In the case of thermal relief valves on piping, capacity and piping pressure drop calculations are not required if they meet the following criteria: a. For Rego style hydrostatic relief valves, the line length protected does not exceed 50m

for uninsulated piping, and 500m for insulated piping. b. For 20 x 25mm ND relief valves with C orifice, and for larger relief valves, the protected

line length does not exceed 1000m.

Records of calculations and notes shall be kept in the Project files.

Note: Features as specified on the data sheets and as specified in Section 10.1 shall be included in the selected valve.

Note: The sizing of bursting discs shall comply with previous guidelines.

6. GASKETS

Gasket material shall be selected from those specified in CSBP Engineering Standard Piping Material Specifications (ES-14-603-01) Appendix 12, Service / Gasket Data Sheet Index for the particular service.




7. PAINTING

Carbon steel valves shall be painted after final testing and assembly in accordance with CSBP Engineering Standard Protective CoatingsES-14-102-12: System D for temperatures 100oC and System G for temperature >100oC.

Note: Stainless steel, aluminium and brass valves should not be painted.

8. IDENTIFICATION

A unique equipment number, assigned in accordance with CSBP Engineering Standard Equipment Numbering System ES-14-101-06, together with the Cold Set Pressure (CSP) shall identify each valve.

Example: 1150PSV1234 CSP 1200 kPa

In the case of small hydrostatic relief valves, the equipment number, and Cold Set Pressure if not marked on valve body, shall be on a permanently attached tag.

Flanged PSVs shall be stamped on the top of the outlet flange rim. All other valves shall be stamped or engraved on the body. Stamps and engravings shall be at least 5mm high.

Note: Precautions must be taken to ensure that the stamping does not disturb the internal components. It should be carried out when the valve is stripped.

Inlet line flanges or screwed connections, to which the valve is connected, shall be stamped with the valve equipment number. An alternative is to permanently attach a numbered tag.

9. DOCUMENTATION

9.1 TECHNICAL DATA SHEET

As a minimum, the following information shall be recorded on Technical Data Sheet Valve Safety Relief (IF1486) for all PSVs: Process medium. Valve Manufacturer Valve model and serial number. Type of valve (conventional or bellows). Valve trim, body and bonnet materials. Inlet and outlet connection sizes. Orifice area. Construction code. Set and back pressures.




9.2 TEST CERTIFICATE

Test certification shall be completed in accordance with Section 10 of this standard.

New valves shall have material certificates and hydrotest certificates supplied. Vendor diagrams and technical information shall be supplied and retained in the project records.

9.3 SAFETY RELIEF VALVE INSPECTION & REPAIR DOCUMENT

Details of the as-received valve condition, repairs and work carried out on the valve shall be recorded on documentation, which meets the requirements of AS 3788 Appendix P.

Note: This document shall accompany the Test Certificate.

9.4 J D EDWARDS COMPUTER SYSTEM (JDE) The JDE system supports and controls inspection, testing and refurbishment for Pressure Relieving Devices. It carries the unique identification of Pressure Relieving Devices enabling complete traceability to be maintained.

The following information is located on the system:

PSV Equipment number Protected Equipment or system number PSV master data Next inspection date

9.5 WORK ORDER HISTORY

The following information from the retest documentation shall be recorded in the Plant Inspection PSV Report:

Run time since last test. Pre-dismantling test lift pressure. Leakage rate after test lift. Cold set pressure. Lift / cold set pressure percentage. Work carried out on the PSV. Any other relevant information that may affect the retest interval.




10. INSPECTION AND TESTING

10.1 NEW PRESSURE RELIEVING DEVICES

All new relief valves must have a current Test Report & Certificate from the Manufacturer that complies with the minimum requirements of AS 1271 - 1997, Appendices B, C or D.

Before installation each relief valve shall be inspected for damage due to handling and transportation. Certificates are to be checked to ensure all valves have been re-tested in accordance with Section 10.3 after delivery from the manufacturer and that numbers and set pressures are correctly and clearly marked on each valve. Relief valves mounted on skids shall be re-tested after delivery to site.

Note: Relief valves do not need to be dismantled and overhauled if they pass the pre-test or they can be adjusted to comply with the code

The pre-installation test shall include verification by a Competent Person that any gags, plugs or similar devices have been removed before the safety valve is installed. Test records shall include a notification that this has been carried out.

Valves shall be re-tested as per Section 10.3 within twelve (12) weeks of commissioning. The final installation shall be carried out after all pipe-alignment, pressure testing and flushing is complete.

Note: Once installed and after re-testing the valve must not be removed from its position unless it is to be re-tested.

10.2 IN-SERVICE PRESSURE RELIEVING DEVICES

All valves that are in service shall be maintained in a serviceable condition to ensure that they will operate correctly if there is an overpressure situation. This shall be carried out as follows:

a. Each relief valve removed from service for testing and calibration shall be removed carefully from the installation, decontaminated, and placed directly in its specific transport package for transit to and from the Testing Contractors facility.

Note: It is vitally important that each relief valve throughout this operation is handled with extreme care as the valves history and future inspection periods are based on pre-test results and as- dismantled condition findings at the testing facility.

b. Any defects or damage noted at the time of removal must be notified immediately to the CSBP Mechanical Inspector.

c. The Testing Contractor is responsible for the testing, repairs, refurbishment and completion of documentation relating to the relief valve, in accordance with the scope of work supplied by the CSBP Mechanical Inspector, and statutory requirements.




10.3 RE-TESTING OF RELIEF VALVES

Re-testing of relief valves includes removing, transporting, inspection, re-conditioning, re-setting, re-installation and re-commissioning. The JDE Service Type is RTEST. The operational procedure is as follows:

10.3.1 Removal

Before removal, check that the connecting pipe flange or screwed connection is numbered with the valve number. If not then affix the valve number as per Section 8. Each valve removed from service for re-testing shall be removed carefully from the installation.

Note: Flogging spanners shall not be used to unbolt relief valves.

Any defects or damage noted at the time of removal must be notified immediately to the CSBP Mechanical Inspector. Flange faces shall have protectors fitted.

10.3.2 Inspection and Testing

A NATA Approved Testing Company shall perform inspection, re-conditioning and testing of all relief valves. Pre-testing, inspection, re-conditioning and final testing shall be in accordance with AS 3788, AS 1271, API RP 576 and API Std. 527 and shall be carried out in a clean and dedicated test environment.

All in-service relief valves, irrespective of the pre-test results, shall be dismantled and overhauled. For Rego hydrostatic relief valves, the test procedure in UL132 shall be used. Testing of soft-seated pop-action relief valves for liquefiable gas service shall be carried out in accordance with AS 3788 Appendix X. The results of the tests, inspections and valve condition shall be recorded on documentation, which meets the requirements of AS 3788 Appendix P.

10.3.3 Security Seals

The adjusting nut or cover shall be secured with a tamper-proof seal.

10.3.4 Numbering

Relief valve shall be numbered while stripped for reconditioning unless numbered as per Section 8.

10.3.5 Re-Installation

Before re-installation the Equipment Support Team Leader (or delegate) shall verify that the relief valve has been set to the correct pressure by comparing the Test Certificate with the original design requirements. The valve shall be installed with new gaskets in accordance with Section 6.

Note: Flogging spanners shall not be used to tighten flange bolts.

After installation and before re-commissioning the Equipment Support Team Leader or the Responsible Officer shall verify that the valve has been installed in the correct location by comparing the valve number with the number on the inlet connection.

Note: The Test Certificate shall be returned to Plant Inspection.




10.3.6 Painting

Refer to Section 7 for painting requirements.

10.4 ON-STREAM INSPECTION AND TESTING OF RELIEF VALVES

10.4.1 Inspection

An In-Service Plant Inspector shall carry out On-Stream inspections of relief valves in accordance with AS3788 and API 576 and record results on CSBP Standard Form PSV On-Stream Visual Inspection Report SF2123.

10.4.2 Testing

Testing of the valve whilst On-Stream, is carried out to verify the set pressure.

The Testing Contractor shall provide their On-Stream testing procedure for CSBPs approval. The procedure shall address the possibilities of the relief valve fully opening and / or not re-seating.

Testing shall be carried out by one of the following methods:

a. By fitting a power assisted lift to the stem via a strain gauge that measures the additional force to lift the disc off the nozzle and then determines the actual set pressure by calculation.

This type of testing includes the use of specialised equipment, which lifts the valve stem while in service (eg. Trevitest), or floating of valves in steam service.

b. By raising the system pressure and noting the pressure at which the valve releases.

This method is used for boiler safety relief valves and positive displacement pumps with kick-back relief valves.

11. INSPECTION OF BURSTING DISCS

All bursting disc locations shall be numbered, flanges stamped or a permanent tag affixed, details recorded in JDE, Preventative Maintenance schedules established and history recorded.

The owner shall be responsible for changing the bursting element after the time period recommended by the manufacturer or based on previous experience.

12. PACKAGING, TRANSPORTATION AND STORAGE

Each relief valve shall be packaged in a manner which protects the valve from damage, and which allows the valve to be transported in the vertical position, except for small Rego style hydrostatic relief valves which does not have to be transported in the vertical position. Where possible all relief valves shall be transported in purpose-built rubber based transport frames or wooden based cages.

Relief valves less than 1 kg, shall be supported in a strong cardboard box surrounded by foam.




Relief valves greater than 1 kg shall be contained individually in a transport frame or wooden crate in an upright position

Where a number of valves are being transported to the same location, they shall be contained in a cage or wooden crate complete with lid, and individually strapped in place.

All packaging shall be marked Handle With Care, and have arrows indicating This Way Up.

Packaging requirements may be changed only with the authority of the CSBP Mechanical Inspector.

The Testing Contractor shall attach with stainless steel wire through the adjustment feature, a Purchase Order Tag (supplied by CSBP) indicating the CSBP Purchase Order Number, and the Contractors Job Number.

All relief valves that are not required for immediate installation shall be stored in a secure under cover location in their transport packaging.

es-14-603-05

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