WYANDOTTE SITE SAFETY AND HEALTH STANDARDS PREVENTATIVE MAINTENANCE - PRESSURE SAFETY RELIEVING DEVICES

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1 Issued by: Site Engineering I. PURPOSE A. To provide a preventative maintenance program for "Pressure Relieving Safety Devices": Safety Valves, Rupture Disks, Conservation Vents, and Flame Arrestors. B. To reduce the possibility of injury to personnel or damage to equipment caused by the failure of pressure relieving devices. II SCOPE This standard applies to all units or departments on the Wyandotte Site. III. DESIGN AND DOCUMENTATION A. Design of pressure relieving devices shall follow all applicable codes and standards. For calculation direction, reference Site Engineering Standard Procedure 25, and Corporate Pressure Relief Design Guidelines. B. Documentation requirements shall be as specified under each unit s preventative maintenance (PM) procedure. In general, these requirements are that each unit maintains a list of all devices in use, as well as manufacturers installation, operation, and maintenance manuals for all devices installed in that unit. Each application will have its own PM file, with technical information (sizing criteria, calculations, setpoint, device specification, etc.) contained or referenced (ie, to on-line documentation system) therein. Typical system for the site uses a two folder system: 1. PM folder for technical and maintenance records on point of service or application; 2. Valve or device folder (also known as an F-15 folder), for individual device history. C. For valves in dedicated service (no spares requiring device history), or for low cost, disposable device applications, operations and maintenance may decide to combine PM and device folders. This is an acceptable practice if the required information is maintained, if the system is documented as procedure, and the procedure is reviewed by operations and maintenance. RDM = WYS&H W-9 Page 1 of 19

2 IV. ACQUISITION A. New devices shall be purchased after sizing and specification is completed following the Engineering Standard Procedure Safety Relief Valve Sizing Guidelines. B. Replacement devices (same manufacturer, make and model number) shall be purchased by providing the vendor with the specification of the existing device. Any other replacement requires review by engineering, and must follow local Management of Change procedures. V. PUTTING DEVICES INTO SERVICE A. Before putting new device into service, PM folder must be established. 1. Replacement device installation requires updating PM folder. 2. Rupture disks require individual folders when installed alone; installations in series with a PSV may be documented via the PSV folders. If documented separately, the rupture disk file should cross-reference the PSV number, to locate the calculations. B. Maintenance representative will inspect, tag, and color code device before installation, per local plant or lab practice (see section IX, Numbering and color convention ). VI PREVENTATIVE MAINTENANCE PROCEDURES A. General PM notes: 1. All devices will have their own PM sheets, reflecting individual applications and manufacturer s recommendations (PSV/Rupture disk combined installations may have one PM sheet). RDM = WYS&H W-9 Page 2 of 19

3 2. Condition of vent piping is as critical as the individual device, and as such, should be inspected at the time of device inspections. 3. Each lab or plant area should clearly designate who is responsible for reviewing and resolving PMs that result in a condition 4 or 5. B. Power boiler valves 1. This class of valves requires inspection, repair and setting by a licensed shop. These valves will be sent to a licensed shop by the Maintenance Shop. The purchase order shall state the following: a) Disassemble, clean valve parts, check measurements, recondition and replace parts as required, reassemble, adjust opening and closing (or reseating) pressures. Steam valves will be checked with steam, not air or water. b) Perform the seat tightness test (ANSI B147.1/API RP527), reseal the blow down ring pin and the top lever pin (per ASME Power Boiler Code) color code the valve, install a metal data plate which shall include capacity, set pressure, date and the National Board VR stamp. Capacity of ASME Code Section I steam valves will be given in lbs. of saturated steam per hour at 3% accumulation. The inlet and outlet connections shall be sealed for return shipment to prevent the entry of dirt and other foreign material. 2. A written service report shall be returned with the valve by the service shop and shall include: a) Describe visual inspection. State one of the following regarding internals: clean, a slight film or coating, or had heavy deposits. State condition of flanges and springs. Comment on corrosion. b) Describe reconditioning and repairs - lapping or machining required, parts replaced, etc. c) Spring number and pressure range, and orifice size. d) Seat tightness leakage rate in bubble per minute. RDM = WYS&H W-9 Page 3 of 19

4 e) A copy of this report will be sent to the Plant Maintenance Shop. The responsible technician in the shop will transfer the information from the report to Form F-15. C. Safety valves (in-house inspection & repair by qualified technicians) 1. Write-up a) Verify PSV folder calculation & specifications information agrees with the device in service and initiate the F-15 form. b) Report to process owner, and correct any discrepancies prior to proceeding. 2. Visual inspection / cleaning a) Perform visual inspection and document findings b) Safety devices which involve hazardous materials must be handled in accordance with W-8 (Contaminated Equipment) and cleaned prior to testing. 3. Testing of As found pressure setting a) The testing apparatus must have sufficient capacity to provide a clean lift (no chatter). b) ASME Section VIII valves (those on vessels rated at >15 psig) in vapor/steam service will be tested with air, and valves in liquid service will be tested with air or water. c) Document the As found setting on the F-15 in accordance with the F-15 rating system (see Appendix A), and on the PM. d) For As found conditions of 4 or 5, see 6. below. RDM = WYS&H W-9 Page 4 of 19

5 4. Disassembly and inspection a) Perform disassembly/inspection per the manufacturer s procedures. b) Note: All critical dimensions must be verified and corrected if necessary, (for example, after lapping or machining, or if excessive wear or other abnormality is observed). Polishing with a 1200 grit (or higher) compound does not require critical dimension check. c) Document findings on the F-15 and on the PM. 5. Re-assembly and testing a) Reassemble & color code per section IX. b) Perform testing to verify set pressure a minimum of three (3) full cycles. Document on the F-15 and PM. c) Note: Valve must lift and not chatter. d) Valve must reseat tightly, and should not leak below 91% to 94% of set pressure, depending on manufacturer s recommendations. A leak test will be conducted to verify seat tightness. e) Set point range vs. Popping Point Tolerance (per ASME Section VIII) 0 to 70 psig 2 psi 71 to 300 psig 3% of set pressure 301 to 1000 psig 10 psi 6. When the equipment owner s representative reviews one of these PM's which shows a "4" or "5" "as found" condition, PM files will be checked to determine if this type has previously failed in the same service. If an assignable cause has been determined, an appropriate note will be made on the PM and F-15, and the PM signed and routed by the equipment owner s rep. If an assignable cause has not been determined, the Daily Support Team (DST) (or designees, or equivalent) should meet to determine corrective action. The results of the meeting will be noted on the PM and F-15. RDM = WYS&H W-9 Page 5 of 19

6 D. Safety valves (in-house inspection, and repair by licensed shop) 1. Perform procedures in section VI.C.1 to VI.C.3, above. 2. Refer to section VI.B (Power Boilers) for instructions to outside shop. E. Each plant or lab will determine those devices that are less expensive to replace than repair. For these designated low cost valves, 1. Perform procedures in section VI.C.1 to VI.C.3, above. 2. Return valve to service, or replace it, disposing of it appropriately, depending on test results. F. Safety relief valves on hot water heaters are designed per industry standards. Visual inspection and replacement on a specified schedule is an acceptable practice. In this application, a PM folder is required, but a valve folder is not, because no valve history is required. G. Pressure relieving devices in non-safety, non-code applications. Local plant or lab will determine appropriate PMs for these devices, with maintenance and engineering support.(these devices may be recognized by designations of PRD or PRV. ) H. Conservation vents, Low Pressure Relief Valves, Emergency Vents, Vacuum Relief Valves, etc. 1. Write-up a) Verify device folder calculation & specifications information agrees with the device in service and initiate the F-15 form. b) Report to process owner, and correct any discrepancies prior to proceeding. 2. Visual inspection / cleaning a) Perform visual inspection and document findings RDM = WYS&H W-9 Page 6 of 19

7 b) Safety devices which involve hazardous materials must be handled in accordance with W-8 (Contaminated Equipment) and cleaned prior to testing. 3. In-place Inspection - In-place inspections of weight-loaded devices are permitted if the following procedure is followed: a) Vessel pressure equalized with atmosphere. b) If vessel contains hazardous material or is blanketed with an inert gas such as nitrogen, a standby person must be present with the appropriate respiratory equipment in accordance with Safety Standard W-14 "Respiratory Protection Policy". All inlet connections must be isolated per Safety Standard W-10, "Lock, Tag, and Try". c) There shall be no materials pumped into or pumped out of vessel during inspection. d) Disassemble valve to expose seating surfaces and weights. Thoroughly inspect valve and document on F-15 and PM "as found" condition in accordance with the definitions in Appendix A, F-15 Practices, section IV. e) Depending on as found results, take the following actions: 1. If the "as found" condition is "1" or "2" the device may be wiped clean, color coded in accordance with the color for the current year (See Section IX) and returned to service. 2. If the "as found" condition is "3" and the device can be cleaned in place, it is permitted to do so. The device may then be reassembled, checked for proper operation, color coded and returned to service. RDM = WYS&H W-9 Page 7 of 19

8 3. If the "as found" condition is "4" or "5", the device must be removed and taken to the Maintenance Shop for cleaning and repair. (Proceed to section VI.H.4.c.3.) 4. Shop Inspection and Repair - If the device is spring loaded or the In-place Inspection "as found" condition of a weight loaded device is a "4" or "5", the device must be removed and serviced in the Maintenance Shop as follows: a) Safety devices which involve hazardous materials must be handled in accordance with W-8 (Contaminated Equipment) and cleaned prior to testing. b) Disassemble valve to expose seating surfaces and weights/springs. Vent springs should be inspected to verify that the set point pressure is within their rated range. A qualified engineer will be consulted whenever the set point is outside the rated range of the spring. Thoroughly inspect the valve and document on F-15 and PM "as found" condition in accordance with the definitions in Appendix A, F-15 Practices, section IV. c) Depending on as found results, take the following actions: 1. If the "as found" condition is "1" or "2" the device may be wiped clean, color coded in accordance with the color for the current year, and returned to service. 2. If the "as found" condition is "3" the device must be cleaned. The device may then be reassembled, checked for proper operation, color coded, and returned to service. 3. The technician must contact the appropriate equipment owner s representative with a report of any vent found in condition 4 or 5 so immediate corrective action can be taken for the vent being installed. 4. The vent will then be overhauled, making any repairs necessary and recording them on the PM and F-15. RDM = WYS&H W-9 Page 8 of 19

9 d) New vents and vents found in condition "5" will be tested to determine that it opens at a specified pressure and vacuum. The vent will be tested a minimum of three (3) full cycles. A vent must open fully, without chattering, at a pressure no greater than the sum of the setpoint plus the tolerance specified by the manufacturer. I. Rupture disks 1. Write-up 1. The vent must reseat tightly in the range specified by the manufacturer. Vents which do not meet these criteria shall not be returned to service. 2. Once the vent PM has been completed, the top bonnet will be color coded. 3. When the equipment owner s representative reviews one of these PM's which shows a "4" or "5" "as found" condition, PM files will be checked to determine if this type has previously failed in the same service. If an assignable cause has been determined, an appropriate note will be made on the PM and F-15, and the PM signed and routed by the equipment owner s rep. If an assignable cause has not been determined, the Daily Support Team (DST) (or designees, or equivalent) should meet to determine corrective action. The results of the meeting will be noted on the PM and F-15. a) Verify rupture disk folder calculation & specifications information agrees with the device in service and initiate the F-15 form. b) Report to process owner, and correct any discrepancies prior to proceeding. RDM = WYS&H W-9 Page 9 of 19

10 2. Both sides of every rupture disk must be visually inspected by a qualified technician in accordance with the procedure and frequency shown on the rupture disk PM sheet. This inspection may be done in place; however, the use of borescopes or similar devices does not permit adequate visual inspection. Therefore, they will not be utilized to perform the visual inspection. a) In-place inspections require compliance with W-18 "Vessel Entry Procedures". b) Installations involving hazardous materials must be handled in accordance with W-8 (Contaminated Equipment). 3. Rupture disks are also used to protect other pressure-relieving devices from corrosion. Inspection of the rupture disk should be part of the routine developed for inspection of the pressure relief valve. 4. Any extraordinary problems discovered during inspection must be reported to the appropriate equipment owner s representative immediately for corrective action. Damaged rupture disks must be discarded rather than repaired. "As found" conditions will be recorded on the PM by the Technician. 5. When the equipment owner s representative reviews the rupture disk PM which shows a failed disk or other problem, PM files will be checked to determine if a previous problem was noted for the same service. If an assignable cause has been determined, an appropriate note will be made on the PM and the PM signed and routed by the equipment owner s rep. If an assignable cause has not been determined, the DST (or designees, or equivalent) should meet to determine corrective action. The results of the meeting will be noted on the PM. 6. Regardless of the results of visual inspection, rupture disks require scheduled replacement, based on specifying engineer s and manufacturer s recommendations, and local experience. The replacement schedule should be documented on the PM. 7. Disks will be stored in such a manner as not to jeopardize the integrity of the disk. RDM = WYS&H W-9 Page 10 of 19

11 J. Flame arrestors 1. Every flame arrestor must be inspected/repaired by a qualified Technician in accordance with the procedure and frequency shown on the PM sheet. This inspection may be made in place. Any evidence of mechanical damage or the presence of more than surface coating, necessitates removal of the arrestor for Maintenance Shop inspection and overhaul. Arrestors which are removed and overhauled will have all repairs recorded on the PM. Any extraordinary problems discovered must be reported to the appropriate equipment owner s representative immediately for corrective action. 2. When the arrestor has been found to be serviceable the top bonnet will be color coded in accordance with the color for the current year 3. When the equipment owner s representative reviews an arrestor PM which required overhaul, PM files will be checked to determine if a previous problem was noted for the same service. If an assignable cause has been determined, an appropriate note will be made on the PM and the PM signed and routed by the equipment owner s rep. If an assignable cause has not been determined, the DST (or designees, or equivalent) should meet to determine corrective action. The results of the meeting will be noted on the PM. K. Internal reliefs (pump, compressor, etc.), or those integral to the design of the equipment. These devices do not require their own PMs or documentation, because they will be maintained with the primary equipment, per manufacturer s recommendations. (These devices should not have an individual tag number on P&IDs). RDM = WYS&H W-9 Page 11 of 19

12 VII. RESPONSIBILITIES RESPONSIBILITIES GRID (L = lead role S = support role) Scenario setting, system design and calculations S L Ensuring vendor provided devices meet site and L S corporate requirements Documentation (See III.B) L S Testing (performing PMs, managing outside L S services, pre-installation testing) Resolution of non-routine test results (including 4 L S S and 5 As Found results) Training S S S L Establish and enforce PM schedule L S S RDM = WYS&H W-9 Page 12 of 19

13 VIII. GENERAL OPERATIONS A. Changes in service 1. All changes in service require review by a qualified engineer. Use of a Management of Change procedure is required for all PSM plants, and is strongly encouraged for other facilities as well. If the change in service requires re-calculation, or re-specification of a valve, fill out a Request for Engineering Service (RES) form, or consult with local engineering team or Technical Engineering Support (TES) manager. In operations using TINMAN, submit a Request for Change (RFC). 2. Changes in set pressure should include a review of existing spring range. Change in set pressure requires the old setpoint and capacity be lined out, and a repair tag with the new setpoint and capacity be installed on the valve. 3. Revisions to vent piping must also be made only in consultation with engineering. B. Follow-up to device relieving or vessel overflow The Process Owner or Department Manager has the responsibility to require an incident investigation when a safety device relieves. The intent of this investigation is to analyze the incident and prevent its recurrence. The incident report should include immediate corrective actions such as performing a special PM to clean the safety valve to ensure that it is still functional. Any corrective action taken as a result of this investigation must be documented in the PM folder. IX. NUMBERING AND COLOR CONVENTIONS A. Each pressure-safety relieving device must have a prefix letter, followed by a number indented into the devices metal surface. (Inlet flange or as near as possible to the inlet connection.) The letters and numerals will be 1/4" high, or as large as possible, and the letters will be assigned for identification in accordance with the Identification Prefix described in the table below. The numbers will be assigned sequentially by the plant Maintenance Shop. EVERY SAFETY RELIEVING DEVICE, EXCEPT RUPTURE DISKS, WILL BE STAMPED. RDM = WYS&H W-9 Page 13 of 19

14 B. Identification Code Identification Department or Area Recipient of F-15 second copy Prefix A Site Main Office Human Resources Manager B Plastic Materials Department Manager C Adhesives Department Manager D Engineered Plastics Compounding Department Manager E Elastocell Department Manager F Expandable Polyolefin Department Manager FB Food Blends Operations Superintendent G Polyol Department Manager H Rail Car Department Manager I Chem. Engineering Department Manager J Chem. Engineering Department Manager K Miscellaneous Department Manager (Maint. Shops, Stores, Engineering & Research) KR Kreelon Department Manager L Thermal Plastic Urethane Department Manager N NPR Operations Superintendent PA PAC Department Manager UA Urethanes Applications Department Manager VA* Vitamin A Operations Superintendent VE* Vitamin E Operations Superintendent VQ Quality Assurance Operations Superintendent Z Steam Facility Responsible Engineering Associate T Livonia Site Plant Manager *Note: Current Vitamins practice is to use P&ID device tag number, in addition to Vx code RDM = WYS&H W-9 Page 14 of 19

15 C. Inspection Color Code The top bonnet of all pressure safety relieving devices will be color coded to indicate the year in which it was newly installed or was last inspected/repaired. Last digit of Year Color 0 Black 1 Brown 2 Red 3 Orange 4 Yellow 5 Green 6 Blue 7 Violet (Purple) 8 Grey 9 White X. REFERENCES ASME Boiler Code, Section 1 ASME Boiler Code, Section VIII API 2000 API 576 Corporate Standard No. 19, Pressure Relieving Devices RDM = WYS&H W-9 Page 15 of 19

16 Appendix A, F-15 Practices I. The permanent maintenance record for pressure safety relieving devices will be maintained on Form F-15 (click here to view F-15). The top portion of Form F-15 must be filled out by the owning department. Since this portion is critical in determining the history of the device, it must be filled out completely. II. When the PM on the valve is completed, the Technician performing the work will sign Form F-15. Distribution of the F-15 form corresponds with local plant or lab needs. A typical practice follows: A. The gold copy will be placed in a plastic envelope and attached to the valve. Once the valve is mounted in service, this copy may be removed and discarded by Operations personnel upon their confirming that the valve is installed for the application stated on the tag. B. The yellow copy will be sent to the appropriate Department Manager as listed on the distribution list maintained in the Maintenance Shop. (See Paragraph IX.B). C. The white copy will be kept in the Maintenance Shop F-15 or valve or device folder. D. The pink copy will be stapled to the safety PM for further routing. III. The "as found" condition for PSVs will be classified and noted on the F-15 in accordance with the following definitions (Note: Slight leaks may be detected by a wet paper towel, or bubble test): 1 Valve is clean, lifts fully within the tolerances shown in the table below, and reseats firmly. 2 Valve is clean, lifts fully within the tolerances shown in the table below, but has a slight leak when reseated. 3 Valve has slight film or coating on interior, but lifts fully within the tolerances shown in the table below, and reseats with no more than a slight leak. RDM = WYS&H W-9 Page 16 of 19

17 4 Valve has heavy deposits on interior but flow capacity is not restricted, lifts fully within the tolerances shown in the table below, and has no more than a slight leak. 5 Valve has heavy deposits restricting relieving capacity, or will not lift fully, or does not lift within the tolerances shown in the table below, or has more than a slight leak after reseating. Table: From ASME Section VIII Set point range Popping Point Tolerance 0 to 70 psig 2 psi 71 to 300 psig 3% of set pressure 301 to 1000 psig 10 psi IV. The "as found" condition for Conservation Vents (and other low pressure or vacuum devices) will be classified and noted on the F-15 or on the PM in accordance with the following definitions 1 Vent is clean -- weights/springs are as described on the PM sheet. 2 Vent is clean on interior -- exterior has slight film or coating - weights/springs are as described on the PM sheet. 3 Vent has slight film or coating on interior -- weights/springs are as described on the PM sheet. 4 Vent has heavy deposits on interior, but flow capacity is not restricted -- weights/springs are as described on the PM sheet. 5 Vent has heavy deposits restricting relieving capacity, or will not lift fully -- weights/springs are damaged or not as described on the PM sheet. RDM = WYS&H W-9 Page 17 of 19

18 Appendix B, Definitions 1. Blowdown -- Difference between set pressure and reseating pressure of a pressure relief valve expressed as a percent of set pressure. 2. Chatter -- Extremely rapid opening and closing of a valve 3. Conservation Vents -- These Devices are all used to protect a vessel or system from damage due to over-pressure or excessive vacuum. The set-points are less than 15 psig (usually inches of water), therefore, the ASME code does not apply. These devices are specified using the guidelines of API Flame Arrestor -- A device whose primary function is to prevent the propagation of fire, by absorbing and dissipating heat, from fire on one side of the flame arrestor, to below the ignition point on the opposite side of the arrestor. 5. Lift -- The actual travel of the disk away from the closed position when the valve relieves. (Full lift typically occurs at 10% overpressure). 6. Pressure Safety Relieving Valve -- An automatic pressure relieving device which may be used as a safety or relief valve, depending upon application: a safety relief valve is used to protect personnel and equipment by preventing excessive accumulation of pressure. 7. Qualified Personnel -- Maintenance personnel required to service safety relieving devices are required to have formal training provided by a recognized professional in this field every three years minimum, and perform such work at an appropriate frequency to maintain the necessary basic skills. 8. Relief valve -- A relief valve is an automatic pressure-relieving device, actuated by inlet static pressure which opens in proportion to the increase in pressure over the opening pressure. 9. Rupture Disk -- A non-reclosing pressure relief device actuated by inlet static pressure and designed to function by the bursting or rupturing of a pressure containing disk at a predetermined pressure. 10. Safety valve -- An automatic pressure-relieving device actuated by inlet static pressure and characterized by rapid opening or pop action. RDM = WYS&H W-9 Page 18 of 19

19 11. Safety relief valve -- An automatic pressure-relieving device characterized by rapid opening or pop action, or by opening in proportion to the increase in pressure over opening pressure, depending on the application. 12. Set Pressure -- Expressed in psig, set pressure is inlet pressure at which the device has been set to open under service conditions. In liquid service, set pressure is determined by the inlet pressure at which the valve starts to discharge a continuous stream of liquid. In gas or vapor service, the set pressure is determined by the inlet pressure at which the valve will pop under service conditions The set pressure for any device must be established by a qualified engineer who is authorized by Site Engineering. The engineer must consider the valve s relieving capacity (Pressure and flowrate), plus the system being protected. Set pressures for safety relief valves and rupture disks must be established according to ASME. Set pressures for conservation vents and other low pressure (less than 15 psig) relieving devices must be established according to API The set pressure for any pressure safety relieving device will be that value which has most recently been established by the authorized engineer and approved by the appropriate equipment owner s representative. If the set pressure must be changed (authorized via engineering) the old set pressure and capacity is to be lined out (still legible) and a repair tag with the new set pressure, capacity, and date must be installed on the valve. 13. Simmer -- Characterized by the audible or visual passage of a fluid across the seating surface of the safety or pressure relief device just prior to opening. In gas or vapor, simmer is the leakage just prior to popping (opening). For liquid service valves, simmer is the non-continuous flow (drops) just prior to becoming continuous. 14. Vacuum relief valve -- A pressure relief device designed to open to prevent an excessive internal vacuum. It is designed to reclose after normal conditions have been restored. RDM = WYS&H W-9 Page 19 of 19