How to extend the service life of high pressure valve

How to extend the service life of high pressure valve

The MAIN FORgings SUCH AS VALVE body shall be inspected by ultrasonic one BY one. There shall be no defect density in all parts. When the initial sensitivity is required to be 2~ equivalent diameter, there shall be no single defect greater than that specified in Table 4. During the sealing test, after the short duration of the test pressure, the relatively large allowable leakage rate through the sealing surface of the seat should conform to the provisions of JB/T9092: there should be no visible leakage at the back of the mounting ring; In the upper seal test, there should be no visible leakage after a short duration of test pressure.
Upper connection: Forging Angle type high pressure valve Technical conditions (1)
4.14.6.2 Ingot or profile with diameter or thickness greater than 80mnL shall be evaluated in accordance with GB/T1979 and shall comply with the provisions of Table 2.
Table 2.
4.14.6.3 Ingot or profile with diameter or thickness greater than 80mm shall comply with the provisions of Table 3.
Table 3
4.15 Non-destructive testing
4.15.1 Compression parts such as steel pipes for valve body and pipe fittings shall be tested by ultrasonic and magnetic powder, and fasteners shall be tested by magnetic powder.
4.15.2 Valve body and other major forgings shall be tested by ultrasonic wave one by one, and there shall be no defect concentration area in all parts. When the initial sensitivity is 2~ equivalent diameter, the single defect shall not be greater than the provisions in Table 4.
Table 4 Defect equivalent diameter
4. 15.3 The sealing surface of valve disc and valve seat shall be subjected to penetration test one by one after processing, and no cracks are allowed.
4. 15.4 All valves with welded joint ends shall undergo penetration testing at the welded end and the inspection result shall be free of harmful defects.
4.16 Pressure test
4.1. 6.1 shell test, in the test pressure of the short duration, in each part of the valve shall not have visible leakage, packing can pretighten to maintain the test pressure. Those who fail to pass the test shall be scrapped and shall not be repaired or repaired.
4.16.2 During the sealing test, after the short duration of the test pressure, the relatively large allowable leakage rate through the sealing surface of the seat should conform to the provisions of JB/T9092: there should be no visible leakage at the back of the mounting ring; In the upper seal test, there should be no visible leakage after a short duration of test pressure.
4.16.3 Valves with other actuation devices shall be inspected by the actuation device to open and close the valve during the sealing test and upper sealing test.
5 Inspection Rules
5.1 Inspection Items
Valves are divided into factory inspection, sampling inspection and type test. The items of various tests shall be specified in Table 5.
Table 5 Inspection items, technical requirements and inspection methods
5.2 Outgoing inspection Every product shall be inspected before leaving the factory, and the inspection shall be qualified before leaving the factory. The outgoing inspection shall be conducted before painting.
5.3 Sampling inspection and type test
5.3.1 After formal production, a sampling inspection shall be conducted periodically or after a certain amount of production has been accumulated.
5.3.2 Type inspection shall be carried out when the product with new design or changed design, material or technology is finalized, or when the relevant national safety supervision institution proposes type test requirements.
5.3.3 Sampling inspection and type test shall be conducted by sampling.
5.4 Sampling quantity Sampling can be randomly selected from the products that have passed the inspection at the end of the production line, from the finished product inventory, or from the products that have been supplied to users but not used and kept in factory condition. The sampling number of each specification is one, and its minimum base number is not less than five. The number of cardinalities available for sampling is not limited to user sampling. For the quality assessment of the whole series of products, two specifications with larger nominal size and one with smaller nominal size were selected for inspection.
6 Test Methods
6.1 Pressure test
6.1.1 Valve shell test pressure and duration shall be in accordance with JB/T9092.
6.1.2 Liquid seal test, low pressure gas seal test and upper seal test, the test pressure shall be in accordance with the provisions of JB Hall 9092, and the throttle valve shall not be sealed.
6.2 Operational performance test
6.2.1 Close the valve with the driving device attached to the valve, open the outlet end of the valve, fill the inlet end with medium, apply 1.1 times the nominal pressure or a large allowable working pressure difference, and then open the valve with the driving device attached to the valve; The VALVE OF a MANUALLY OPERATED VALVE SHALL BE OPENED BY A HUMAN HAND USING THE HANDLE (WHEEL) OF THE VALVE OR THE HAND WHEEL OF THE worm gear REDUCTION MECHANISM.
6.2.2 Partially open the valve, close the outlet end of the valve, fill the valve with medium, apply 1.1 times the nominal pressure, and then close the operating valve with the driving device attached to the valve; The VALVE OF a MANUALLY OPERATED VALVE SHALL BE CLOSED BY A HUMAN HAND USING THE HANDLE (WHEEL) OF THE VALVE OR THE HAND WHEEL OF THE WORM GEAR REDUCTION MECHANISM. Then leave the valve outlet open and the valve should remain sealed.
6.3 The chemical composition test of valve body materials shall be analyzed on the body of the valve body, and the cuttings sampling shall be 6.5mm below the surface.
6.4 Mechanical properties of the forging material of the valve body shall be carried out with test bars of the same furnace number, forging batch and heat treatment batch of the valve body according to the method specified by GB/T228.
6.5 Intergranular corrosion test of austenitic stainless steel test bars with the same body number, same batch of forging, same batch of heat treatment shall be tested in accordance with the relevant standards. If necessary, sample from valve body for testing.
6.6 Non-destructive testing The relevant provisions of JB/T6903 for ultrasonic testing, and the magnetic particle testing shall be in accordance with the relevant provisions of JB/T6439.
6.7 Checking Marks on the Valve Body Check the marks printed on the surface of the valve body.
6.8 Check the nameplate content. Print marks on the nameplate of the valve.
7 logo
7.1 Contents of the Mark Valves shall be marked in accordance with 7.2 and 7.3.
7.2 Marks on the valve body The following permanent marks shall be marked on the valve body:
Manufacturer’s name or trademark mark;
– Body material or code;
Nominal pressure;
- nominal size;
- Direction marking
- Forging batch number;
- Serial number of production series.
7.3 Marks on the nameplate
The nameplate shall contain the following contents:
Name of manufacturer
Nominal pressure;
- nominal size;
– Relatively high allowable operating temperature and corresponding relatively high allowable working pressure;
– Relatively high allowable operating pressure difference (when the pressure difference is limited);
- Valve body material.
How to extend the service life of high pressure valve
How to extend the service life of high pressure valve
Ultrahigh pressure valve has been widely used in superhard material manufacturing, chemical industry, petrochemical industry, processing technology, isostatic pressure processing, ultra-high static pressure extrusion, powder metallurgy, metal forming and geophysical, geological research and other fields. Ultra-high pressure valves can be used to control the flow of air, water, steam, all kinds of corrosive media, mud, oil, liquid metal and radioactive media and other types of fluids. The opening and closing part is a disc shaped valve plate that rotates around its own axis in the valve body to achieve the purpose of opening and closing or adjusting.
1, avoid work under small open degree of ultra-high pressure valve, if small open needle valve lift or open slow, work in a small open degrees throttling, small gap erosion is serious, appropriately increase the pitch of locking mechanism, enlarging the opening speed and lift, increases the job opening, make the throttle gap is big, scour is abate, can improve the service life.
2, avoid the ultra-high pressure valve working in high temperature medium, medium temperature has a great impact on the life of the valve, the higher the medium temperature, the shorter the life of the ultra-high pressure valve, otherwise the longer. Therefore, adding cooling device at the pressure relief valve can also significantly improve the service life of the valve.
3. Under different working pressures, use the corresponding sealing pressure, select the appropriate sealing specific pressure, use torque wrench for locking, or realize the automatic control of the ultra-high pressure valve, so as to avoid the valve needle when not subjected to erosion and wear and seat extrusion damage.
4, regular filter ultra-high pressure valve high pressure medium and clean filter, add liquid to make the application of filter filtering. When used frequently, the cycle should be shortened appropriately. Clean the oil tank regularly and replace the new medium at the same time. According to the actual situation of the equipment, the cleaning and oil change cycle can be shortened.
5, installation or replacement of ultra-high pressure valve needle valve should be properly cleaned. To avoid bringing debris to accelerate the wear of the needle valve.
Ultrahigh pressure valve has been widely used in superhard material manufacturing, chemical industry, petrochemical industry, processing technology, isostatic pressure processing, ultra-high static pressure extrusion, powder metallurgy, metal forming and geophysical, geological research and other fields. Ultra-high pressure valves can be used to control the flow of air, water, steam, all kinds of corrosive media, mud, oil, liquid metal and radioactive media and other types of fluids. The opening and closing part is a disc shaped valve plate that rotates around its own axis in the valve body to achieve the purpose of opening and closing or adjusting.