2.0 Dates and Times Tests to be carried out starting Monday 28 Nov for completion Friday 2 Dec.

Transcription

1 MS No: :. A 1.0 Scope of Work Preparation notes: delete column before issuing. 1.1 General Description of Works, Location & Boundaries Strength and tightness testing of Glycol System between plant room and first cooler valve stations in roof void using Oxygen Free Nitrogen. Example, edit as applicable 1.2 Equipment to be Installed / Removed / Isolated Balance lines to be install around check valves xyz (GS4 24(b)) Relief valves xyz to be removed. Pressure Transmitters xyz to be isolated 2.0 Dates and Times Tests to be carried out starting Monday 28 Nov for completion Friday 2 Dec. Strength tests to be carried out at times when areas can be clear of all personnel. 3.0 Monitoring and Witnessing The competent person in charge of the test must be present during initial pressurising of the system, whilst the system is being raised to and held at strength test pressure and until the system pressure has been reduced in pressure for examination. Edit as applicable Edit (times &) dates Identify specific time if applicable A normal requirement The pressure source must not be left unattended while not isolated from the system. The customer (Mr Everright, tel ) to be notified 15 minutes before system is expected to reach strength test pressure. Test duration is NOT to be extended to await his arrival. The customer (Mr Everright, tel ) to be notified when system reaches Maximum Allowable Pressure. The system is not to be raised to full strength test pressure until the customer is present or has given his consent for the test to proceed. Examples only edit/delete as applicable 4.0 Resources Sections 6 to 12 should be used before completing Sections 4 and Supervision, Labour, Qualifications and Training Engineer - Gary Carpenter Star pressure test trained Oct 05 Page 1 of 9

2 MS No: :. A Second Man Joe Brown Star ST1 Engineer 4.2 Tools and Equipment to be used, Certification and Notes OFN Pack(s) Pressure test manifold from London branch Test hoses Ammonia charging hose tested 09/12/04-6mm st.st. tube and fittings Regulator 230 to 40 bar Safety valve (see SS125 Sect 3.0) 10 bar Calibrated gauge B , calibrated 29/9/05 Torches Soapy bubble solution with containers, paint brushes and/or sprayer. Barrier tape and pressure test warning signs. 4.3 Personal Protective Equipment The following PPE will be worn at all times: Safety Boots, Overalls, Safety Helmet. Flame Retarded High Visibility Vest. The following PPE will be worn at appropriate stages in the operation as detailed in the Relevant Documents in section 11: Gloves, Hearing Protection, Safety Harness, Eye Protection. Note: Regulation 40 bar outlet except for CO 2 Note: Gauge workings within 20% - 80% range Fairly standard requirements Page 2 of 9

3 MS No: :. A 5.0 Detailed Sequence/Method of Working Engineer and second man to initial each section as test proceeds 5.1 test pressures from diagram of connections: Initial Examination (max 10% MAP) 0.8 bar Maximum Allowable Pressure 8.0 bar Strength Test 8.8 bar Tightness Test 8.0 bar 5.2 Prepare System Pressure Test Record SF identifying extent of test and components to be included in or isolated from test. Refer to SS113 for further guidance. 5.3 that all vessels have previously been (hydraulically) strength tested to a pressure higher than the current OFN strength test pressure. 5.4 Inform the customer that a pressure test is to take place and the restrictions which will apply. what witnessing, if any, they require see Survey the system and identify the exclusion area (see 7.1) typically people must be kept outside the building or a minimum of 30 meters from the components under test. (SS 125 Sect 5.4. and GS4 27(b)) 5.6 Identify a safe working area for setting up the test equipment typically behind a brick wall and out of line of site to condensers, pipework or other components under test. 5.7 Establish a safe means of discharging nitrogen to atmosphere (not a confined space) without entering the exclusion area. 5.8 Check system for tightness. 5.9 that applicable valves are open or closed that applicable items are isolated or removed for the test e.g. relief valves (see 1.2) and balance lines are installed around check valves as required (see 1.2) all systems, vessels, etc. connected to section under test are vented to prevent pressure build up should isolation valves pass Set up test equipment in safe area correct regulator is fitted (230 bar or 300bar) correct calibrated gauge (20% to 80% of Eng. Inits. 2 nd Man Inits Preparation notes: delete column before issuing. Edit pressures as applicable. Edit if necessary e.g. refer to appended sketch of exclusion area Refer to sketch if applicable Page 3 of 9

4 MS No: :. A range) is fitted correct safety relief valve is fitted (see 5.1) and is correctly located in accordance with SS Secure any single OFN cylinders in a vertical position and restrain charging line with tie wraps or equivalent correct PPE is being worn (see 4.3) 5.19 Set regulator outlet pressure to not more than 10 bar above initial examination pressure (see 5.1) 5.20 Gradually introduce nitrogen into the system until the initial examination pressure is reached (see 5.1). Isolate the system from the nitrogen supply. NEVER LEAVE THE PRESSURE SOURCE UNATTENDED WHILE OPEN TO THE SYSTEM UNDER TEST Enter exclusion area and carry out a visual /aural inspection of the system for obvious leaks. If necessary use a soapy bubble test to pinpoint leaks If any repairs are required, isolate as applicable and reduce that section of the system to atmospheric pressure before proceeding Repeat steps 5.15 to 5.17 until all obvious leaks have been repaired Cordon off exclusion area, place signs prohibiting access and ensure all personnel have left Set regulator outlet pressure to not more than 5 bar above strength test pressure (see 5.1) 5.26 From the safe area, slowly introduce the nitrogen into the system until the strength test pressure (see 5.1) is reached. NEVER LEAVE THE PRESSURE SOURCE UNATTENDED WHILE OPEN TO THE SYSTEM UNDER TEST. CAUTION: No-one may approach the system during this phase unless the following procedure is followed: a) Isolate the system from the nitrogen supply. b) Working from within the safe area, reduce the system pressure by at least 1 bar or 10%, whichever is the larger. c) The system may now be approached. d) If any leaking flanged joints and screwed fittings require tightened or if any other repair is required, that section of the system must be isolated and reduced to atmospheric pressure before proceeding with the repairs. A safe If known, the location of cordons and signs can be detailed here. Add customer witness note if applicable. Page 4 of 9

5 MS No: :. A means of discharging nitrogen to atmosphere must be used. e) After repairs, slowly re-introduce nitrogen into the vented section. f) From the safe area, proceed with the strength test When the strength test pressure is reached, isolate the system from the nitrogen supply and hold the strength test pressure for 5 minutes Reduce the pressure in the system tightness test pressure (see 5.1) and hold for the duration of the tightness test. At this stage general access restrictions can be lifted, signs removed and the system can be approached Leave the plant to stand under pressure for at least 30 minutes, monitoring the gauge for a fall in pressure which might indicate a leak (the drop test). During the drop test, or later as convenient, test for leaks using soapy bubble solution. REPAIRS a) If any leaking flanged joints and screwed fittings require tightened or if any other repair is required, that section of the system must be isolated and reduced to atmospheric pressure before proceeding with the repairs. A safe means of discharging nitrogen to atmosphere must be used b) After repairs, slowly re-introduce nitrogen into the vented section. c) Bring the system back up to tightness test pressure (see 5.1) with additional nitrogen if required d) If the leak repairs involved cutting or welding of the pressure envelope, repeat the strength test. e) Repeat the drop test f) Repeat the soapy bubble test on the repairs only. Add customer witness note if applicable. Add customer witness note if applicable. Add Helium sniffer if applicable 5.30 Reduce the pressure in the system to atmospheric. Or perhaps a 0.5 bar holding charge 5.31 that there is no trapped pressure in the system e.g. behind check valves Inform customer that the tests are complete Dismantle test equipment and return it to store. Page 5 of 9

6 MS No: :. A 5.34 Replace items removed for pressure test (see 1.2) Complete the System Pressure Test Record (SF.052). Revision Revision Notes* Name (print) Signature Date A First Distribution I confirm that I have read and understood this Method Statement and the associated Risk Assessment(s) and COSHH Safety Data Sheet(s). Should circumstances change which invalidate this Method Statement or prevent the Control Measures being implemented, work shall be suspended until the Method Statement has been reviewed by the author or other suitable, competent, person and, if necessary, revised. MS Name (print) Signature Company Date Method Statement Preparation Checklist and Additional Notes use before completing Sections 4 and 5 above 6.0 Tools and Equipment to be used, Certification and Notes 6.1 Lifting Equipment Plant Room lifting beam to be used for lifting OFN cylinders into plant room. Hoist certificates held in site office 6.2 Access Equipment Mobile scaffold tower and ladders to be used for access to leak test welds and fittings as required. Inspections per general site routine. Example only Example only 6.3 Vehicles and Plant Not applicable Page 6 of 9 Edit if

7 MS No: :. A 6.4 Portable Equipment Certification (see section 4.2 for listing) to be held in site office: Pressure test manifold Test hoses Regulator Safety valve Gauge 7.0 Summary of Control Measures See Relevant Document referenced in section 11 for full details 7.1 Permits/Access restrictions/signs See attached sketch reference Appendix 1 for details of exclusion area. 7.2 Access and Lighting Access to plant room via staircase Temporary lighting available in Plant room Torches available to supplement required certificates available Examples only Examples only 7.3 Storage and Disposal of Materials Nitrogen packs to be stored in caged compound when not in use. Nitrogen to be released to atmosphere after use 7.5 Information/Action by Customer Customer to observe and co-operate with exclusion areas during strength test Edit if caged compound is not available. 8.0 Emergency Arrangement As site procedure detailed at induction 8.1 First Aid First aid kit available in Star site office 8.2 Fire No significant risk. 8.3 Chemical Leaks No significant risk 8.4 Incident Reporting Any incidents or near misses to be reported to Star Site Manager and the Main Contractor/Customer Form SF 807 to be completed for a near miss. Add details of any site first aid facility Modify if not so Modify if not so 9.0 Temporarily Amended Systems Page 7 of 9

8 MS No: :. A 9.1 Plant Isolation and Alterations Not Applicable 9.2 Traffic Routing Not Applicable 10.0 Statutory Records Not Applicable? Or insert details of rerouting of vehicular and personnel traffic 11.0 Relevant Documents 11.1 Risk Assessments RA OFN pressure testing of package unit piping, site pipe work & pre-fabricated pipe and component assemblies copy available in the Star site office Material Safety Data Sheets Oxygen Free Nitrogen copy available in Star site office 11.3 COSHH Assessment COSHH A.016 Oxygen Free Nitrogen & OFN-Helium copy available in Star site office 11.4 Star Standard Specifications and Technical Bulletins Standard Specification No. 125 Pressure Test Procedures copy available in Star site office Standard Specification No. 113 Pressure Test Certification of Systems copy available in Star site office 11.5 Drawings 11.6 Other Not Applicable If library risk assessment is not applicable a site specific one will be required. copy is held on site. copy is held on site. copy held on site. copy is held on site. Insert DoC drawing Nos 12.0 Additional Information 12.1 Add site specific additional Page 8 of 9

9 MS No: :. A 12.2 info Page 9 of 9