SHS 01030-92(英文版) 阀门维护检修规程

The Chinese version of standards has precedence to their English translations which are only for internal reference.本英文版为内部资料，仅供参考，以中文版为准。Maintenance and Service Procedure for Petrochemical Equipment General EquipmentMaintenance and Service Procedure for Valves阀门维护检修规程SHS 01030-92(For Trial Implementation)Promulgated by SINOPECSINOPEC Publishing HouseContents1. General 2. Period and Content of Maintenance3. Maintenance and Quality Standard4. Testing and Acceptance5. Service and TroubleshootingAppendix A Option of Materials for Abrasive Tools (For Reference)Appendix B Codes and Application Ranges of Abrasive MaterialsAppendix CSize Ranges of Abrasive Materials (For Reference)Appendix DOption of Flanges, Bolts and Gaskets (For Reference)Appendix EOption of Common Packings1. General 1.1 Subject Matter and Application Range 1.1.1 In this Procedure the period and content of the maintenance, maintenance and quality standard, testing and acceptance, service and troubleshooting of general-purpose valves are defined or described.1.1.2 This Procedure is applicable to such gate valves, stop valves, ball valves, butterfly valves, check values and safety valves that are used in the Petrochemical industry with the max. working pressure being 98.1 MPa (gauge pressure) and the working temperature ranging from -196 to + 850C.1.2 Reference for Preparation SY-21019-73 Maintenance and Service Procedure for Valves of Refineries GB 12241-12243-89 Safety Valves ZBJ16-006-89 Tests and Checks of Valves.2. Period and Content of Maintenance2.1 Maintenance PeriodThe maintenance period of valves shall be determined by all enterprises themselves in accordance with the features of the production plant, performances of the medium, corrosion speed and operating cycle.2.2 Maintenance Content2.2.1 Clean and check the valve body and partial valve parts.2.2.2 Replace or repair partial valve parts.2.2.3 Lap the seal surface.2.2.4 Repair the surfaces of the spacer flange and end flange.2.2.5 Replace or add the packing, replace the gasket.3. Maintenance and Quality Standard3.1 Preparatory Work for Maintenance.3.1.1 Get ready all related technical documents.3.1.2 Get ready all necessary machines and tools, measuring tools and materials.3.1.3 Thoroughly remove the valve medium as per the related regulations on safety.3.2 General Requirements.3.2.1 There shall be a label hung on the valve, indicating the maintenance no. working pressure, working temperature and medium.3.2.2 For removed parts which have special requirements for the direction and position, such direction and location shall be checked for correctness or marked out.3.2.3 Clean all the valve parts, removing all contaminants from them.3.2.4 Replace all the non-metallic seal surfaces that are damaged.3.2.5 For correct selection and use of the materials for abrasive tools and abrasive materials, refer to Appendices A (For Reference), B (For Reference) and C (For Reference) respectively.3.2.6 For bolts and gaskets the working temperature of which is above 250C, appropriate anti-seizure agent shall be applied on them.3.2.7 Copper gaskets shall be annealed before installation.3.2.8 All bolts shall be installed neatly. For gate valves and stop valves, the bolts of the spacer flanges shall be tightened when the valves are in the open state.3.3 Quality standard of Maintenance3.3.1 The valve nameplate shall remain intact and the lead seal of the safety valve shall keep sound and perfect.3.3.2 The valve casting shall have no such defects as cracks, serious shrinkage cavities and slag inclusion.3.3.3 The surface of the valve forging to be machined shall have no such defects as sandwiching, double-skin, cracking and black spots.3.3.4 The weld joint of valve weldment shall have no such defects as cracks, slug inclusion, gas holes, and poor formation.3.3.5 The bolt of the valve shall not be loosened and the end of the bolt shall be 2-3 threads out of the nut. The parts of the actuating system shall be complete and operable.3.3.6 Seal Surface3.3.6.1 The seal surface shall be checked for proper imprint of the contact surface with the developer.a. For gate valves, stop valves and check valves, the imprint lines shall be continuous with the width being not less than 1mm and the imprint being uniform. The extreme position of the imprint line of the gate valve disc on the seal surface shall be no less than 3mm from the excircle (including the width of the imprint line).b. The imprint line of the ball valve shall be continuous with the width being not less than that of the outer diameter of the seal ring of valve body and the imprint being uniform.3.3.6.2 The cumulative decrease in thickness of the seal surface of the safety valve after lapping shall be not more than 2mm.3.3.6.3 The thickness of the build-up welding layer of the safety valves seal surface shall not be less than 2mm.3.3.6.4 The roughness of the seal surface after lapping shall not be lower than 1.6 and not be lower than 0.4 for safety valves.3.3.7 Valve Body, Valve Bonnet and Gaskets3.3.7.1 The connection between the valve seat and valve body shall be firm, tight and free of leakage.3.3.7.2 The valve disk fits the guide perfectly and there shall be no jamming and derailing at any position.3.3.7.3 The max. out-and-in fit clearance of the spacer flange of the valve shall meet the requirements set out in Table 1.Table 1mmSpacer Flange Dia.428590-125130-180185-250255-315320-400405-500Max. Clearance0.400.450.500.550.650.750.803.3.7.4 The seal surface of the flange shall be clean and free of scraps.3.3.7.5 Dyeing inspection shall be made for the contact surface of the steel gasket and seal box and the imprint line shall be continuous.3.3.7.6 The flanges shall be parallel and the installation distance shall be in compliance with the requirements of Table 2.Table 2mmNominal Diameter DN100150200250Min. Installation Clearance22.533.3.7.7 For selection of flanges, bolts and gaskets, refer to Appendix D (For Reference).3.3.7.8 The bolts for which special requirements for tightening moments are set shall be tightened in accordance with such requirements and the error in respect of the tightening moment shall not be bigger than 5%.3.3.7.9 The max. fit clearance of the packing gland and bottom sleeve with the ports of the stuffing box shall meet the requirements set out in Table 3.Table 3mmBore of Stuffing Box 222628343644487075106122Max. Clearance0.200.250.270.300.350.403.3.7.10 The max. fit clearance between the inside diameter of the packing gland and the valve stem shall be in compliance with the requirements set out in Table 4.Table 4mmValve Stem Dia.1416182224283250558090Max. Clearance1.001.201.401.501.802.203.3.7.11 The packing gland shall be free of any damages and deformation.3.3.8 Actuating Device3.3.8.1 The connection between the valve stem and actuating device shall be reliable and shall not become loose of itself.3.3.8.2 When the end of the valve stem is connected with the valve disk at the time when the valve is closed, the disk shall aligned with the valve body.3.3.9 Valve Stem3.3.9.1 There shall be no pits, scraps and axial clefts on the surface of the valve stem and the roughness of such surface shall be 1.6.3.3.9.2 The tolerance value of linearity along the whole length of the valve stem shall be in compliance with the requirements set out in Table 5.3.3.9.3 The tolerance value of roundness of the valve stem shall be in compliance with the requirements set out in Table 6.Table 5mmWhole Length of Valve Stem L50050010001000Tolerance of Linearity0.300.450.60Table 6mmValve Stem Dia.Tolerance of Roundness3030505060600.090.120.150.183.3.9.4 The tolerance value of axiality of the axes of the buttress thread and the upper seal cone with the axis of the valve stem shall be in compliance with the requirements set out in Table 7.Table 7mmWhole Length of Valve Stem L50050010001000Tolerance of Axiality0.150.300.453.3.9.5 The head of the valve stem shall be free of any indentations and deformation.3.3.9.6 The sphere at the end of the stem of the safety valve shall be round and smooth.3.3.9.7 The surface of the safety valve spring shall be free of cracks and the bearing planes of both the ends of the spring shall be perpendicular to the axis.3.3.10 Nuts of Valve Stem3.3.10.1 The max. fit clearance of the excircle of the valve stem and the support opening shall meet the requirements set out in Table 8.3.3.10.2 The hand wheel and bearing gland shall not be loosened.Table 8mmOutside Diameter3550558080Max. Fit Clearance0.250.300.353.3.11 Packing Seal3.3.11.1 The packing for miter joint shall have an oblique angle of 30 made and the joints of every two neighboring turns of the packing shall be staggered by 120 and the packing shall be compressed fast turn by turn.3.3.11.2 After the stuffing is inserted, the packing gland shall be pressed into the stuffing box by no less than 2mm. The exposed portion shall not be less than two thirds of the height of the packing gland that can be pressed into the stuffing box.3.3.11.3 After the packing is filled, the valve stem shall rotate, go up and down freely without seizure and leakage.3.3.11.4 For selection of appropriate packing materials, refer to Appendix E (For Reference).3.3.12 Assembling of Valve3.3.12.1 When the double parallel slides of the valve reach the “Close” position, the expander mechanism shall open immediately to enable the slides to coincide with the seal surface of the valve body. The slides shall not separate or come off during operation.3.3.12.2 The flange and guide bushing of the safety valve body shall be aligned for fitting.3.3.12.3 The indicating and limit mechanisms shall be correctly located.3.3.12.4 The installation of the actuating device shall ensure flexibility and operability of the device and meet the relevant technical requirements.4. Testing and Acceptance4.1 General requirements4.1.1 When making the sealing test, no grease shall be applied on the seal surface. However, it is allowed to have a coat of protecting agent with the viscosity being not greater than that of kerosene applied on it.4.1.2 For valves of Austenitic stainless steel, the test medium shall be mater and the chlorine content of the water shall not exceed 25 ppm. For valves of carbon steel and 16 Mn R, the water temperature shall not be lower than 5 and for valves of other low-alloy steel, the water temperature shall not be lower than 15.4.1.3 When the gas pressure test is made instead of the hydraulic test, the approval from the relevant authority shall be obtained and corresponding preventive measures taken beforehand.4.1.4 After the pressure test is completed, the fluid deposited in the valve chest shall be removed immediately.4.2 Pressure Test of Common Valves4.2.1 Test Medium4.2.1.1 For test of the valve casing, tests on high-pressure upper seal and high-pressure seal, the medium shall be water, kerosene or any non-corrosive fluid with the viscosity not bigger that of water.4.2.1.2 For tests on low-pressure seal and low-pressure upper seal, the medium shall be air or any inert gas.4.2.2 Test Pressure4.2.2.1 For test of the valve casing, the test pressure shall be 1.5 times the nominal pressure.4.2.2.2 For tests on high-pressure seal and high-pressure upper seal, the test pressure shall be 1.1 times the nominal pressure.4.2.2.3 For tests on low-pressure seal and low-pressure upper seal, the test pressure shall be 0.6 Mpa.4.2.2.4 For the sealing test of the check valve, the test pressure shall be the nominal pressure.4.2.3 Test Duration and Permitted Max. Leakage4.2.3.1 The pressure-holding time of the test of the valve casing shall be in compliance with the requirements set out in Table 9. There shall be no leakage from and structural damage to the casing (including the stuffing box and spacer flange).Table 9Nominal Dia. ,mm250Pressure-holding Time, min1234.2.3.2 The pressure-holding time of the seal test and upper seal test shall be in compliance with the requirements set out in Table 10. The allowed max. leakage rate of the seal box shall be in compliance with the requirements of Table 11.Table 10Nominal Dia., mm500Pressure-holding Time sSeal Test153060120Upper Seal Test15 Table 11Nominal Dia. DNGate Valve, Check Valve Drop or No. (of Bubbles)/minPlug Valve Drop or No. Of Bubbles/minAll Valves with Elastic SealBall Valve, Butterfly Valve with Metallic SealCheck Valve with Metallic SealLiquid TestCm3/minGaseous TestM3/h5065150200300350012202801220280* When leakage is measured on the basis of gas, one bubble (volume under the barometric pressure) = 300mm3 and When measured on the basis of liquid, 16 drops = 1000mm34.3 Pressure Test of Safety Valve4.3.1 Pressure Test on StrengthThe pressure for the strength test shall be 1.5 times the max. working pressure. For pressure-holding time, see Table 12. If the results show no leakage and deformation, the strength shall be considered up to standard.4.3.2 Test on Setting Pressure (or Cracking Pressure)4.3.2.1 The setting pressure value of the safety valve shall be that specified on the design drawing. In case no definitely specified value is available, it shall be determined as per the following formulae, taking into consideration different working pressures:When PW0.7, PS=Pw+0.05When 0.746.46.4Pressure-holding Time, min505065658080100100125125150150200200250250300300350350400400450450500500600222222334444552234455678991012344567911131517192224When 1.8PW8, PS=1.1PWWhen 8PW32, PS=1.05PWWhere,PW max. working pressure of the container, MPa;PS setting pressure value of the safety valve, MPa.The max. setting pressure value of the safety valve shall not exceed the designed pressure of the container.4.3.2.2 For the test medium, see Table 13.4.3.2.3 During the test, the pressure adjustment through the regulating sleeve will be made only when the inlet pressure is reduced below 80% of the setting pressure value.Table 13Media Applicable to Safety ValveMedia for TestSteamSteamAir and Other GasesSteam, Air or Any other Gas with Known PropertiesWater and Other LiquidsWater or Any other Liquid with known Properties4.3.2.4 The setting pressure test shall be made for three times.4.3.2.5 For the tolerance of the setting pressure value, refer to Table 14.Table 14Setting pressure MPaAllowed Deviation MPa0.50.50.0143% Setting pressure4.3.3 Pressure Test of Seal4.3.3.1 The pressure value for the seal test: When steam is used as the medium, the pressure value shall be 90% of the setting pressure. When a gas or liquid is used as the medium, the pressure value shall be 0.3MPa lower than the setting pressure if the setting pressure is lower than 0.3MPa and 90% of the setting pressure if the setting pressure is higher than 0.3MPa.4.3.3.2 For media used for seal tests, refer to table 13.4.3.3.3 For pressure tests of seals: If the medium is steam and the test results prove that no leakage has been found and no sound has been heard, the seal shall be considered up to standard; if the medium is a gas, the leakage rate shall be in compliance with the requirements set out in Table 15 and if the medium is a liquid and no leakage occurs within the first 2 minutes, the seal tested shall be considered as qualified.4.4 AcceptanceTable 15mmType of Safety ValvePassageway Dia.mmAllowed Max. Leakage Rate, No. Of Bubbles/minNominal Pressure PN, MPa1010Common Safety Valve204060202030Balanced Back-Pressure Safety Valve2050752030454.4.1 The valve shall operate with the plant for a week and each index set for it shall be in compliance with the relevant technical standard or meet the requirement of production.4.4.2 The valve proves to be perfect and the lead seal of the safety valve is qualified.4.4.3 Two copies of records of the valve pressure test, records of setting pressure test of the safety valve and the certificate acceptance of the set pressure test of the safety valve complete with signatures of the user and maintenanceing units shall be submitted with each party holding one copy.5. Service and Troubleshooting5.1 Routine Maintenance5.1.1 Check the oiling cup, nozzles and lubrication conditions of the thread and nut of the valve stem regularly.5.1.2 Check the seal and fastening pieces of the valve regularly and take remedial measures immediately in case any leakage or looseness is found.5.1.3 Regularly clean the pneumatic and hydraulic devices of the valve.5.1.4 Regularly check the corrosion-resistant coat and thermal insulation layer of the valve. If any damages to them are found, get them repaired immediately.5.2 Common Faults and Remedies (See Table 16)Table 16Serial. NoSymptomPossible CauseRemedies1Valve wont open1. Packing is too tight and the packing gland has biased;2. The valve stem is bending, the thread of the valve stem is damaged and there is dirt deposited on the stem;3. The gate valve requires too great force to close or the valve stem expands due to being heated;4. The bearing cover of the support becomes loose and makes the hand wheel seized;5. The valve is frozen in winter.Adjust the tightness of the stuffing box bolts and straighten out the packing gland;Straighten out the valve stem, repair the thread of the valve stem and remove dirt from it;Knock at the flange of the valve and at the same rotate the hand wheel;Refix the bearing cover;Heat the valve appropriately with steam.2Leakage of packing1. The packing gland becomes loose;2. The packing is insufficient;3. The technical performances of the packing are not in compliance with the relevant requirements;4. The valve stem is rough, bending and has axial grooves.Press the packing gland tight;Add packing;Replace packing;Improve the finish of the surface, straighten out the valve stem and remove the grooves by lapping.3Leakage from the spacer flange1. The bolts of the flange are unevenly tightened;2. The technical performances of the gasket fail to meet relevant requirements;3. The seal surface of the flange has defects.Ensure the bolts are tightened with the uniform torque;Replace the gasket;Repair the seal surface.4Internal leakage of the valve1. There are foreign matters in the valve and the seal surface is stained with contaminants;2. The sphere at the end of the valve stem has become deformed or hangs in the air3. The opening mechanism of the double-slide gate valve is worn out.4. The seal surface is damaged.Remove the foreign matters;Repair the sphere;Get the opening mechanism repaired;Repair by lappingAppendix A Option of Materials for Abrasive Tools(For Reference)MaterialApplicationCast IronApplicable to lapping work of different nature (grinding with coated or built-in abrasives). It can ensure lapping quality and high lapping efficienc