Valve pressure test and valve body sealing deputy sealing performance test Introduction to the relevant standards for valve electric devices
Pressure test is the basic test of valve. Each valve shall be pressure tested before leaving the factory. At present, steel valves are generally pressure tested according to JB/T 9092 standard. Iron and copper valves and forgings and castings of valves shall be subjected to pressure test according to GB/T 13927. The shell test of the valve is the pressure test of the whole shell of the valve, which is connected with the valve body and cover. The purpose is to test the tightness of the body and bonnet and the pressure resistance of the whole housing including the joint of the body and bonnet.
Pressure test is the most basic valve test. Each valve shall be pressure tested before leaving the factory. At present, the domestic valve pressure test standards are GB/T 13927-1992 “general valve pressure test” and JB/T 9092-1999 “valve inspection and test”. GB/T 13927-1992 is a reference to the national standard ISO 5208-1991 “industrial valve pressure test” formulated, JB/T 9092-1999 is a reference to the American Petroleum Institute standard API 598-1996 “valve inspection and test” formulated. GB/T 13927 mainly specifies the pressure test of gate valve, globe valve, check valve, plug valve, ball valve, butterfly valve, diaphragm valve, etc. The JB/T 9092 standard is suitable for the pressure test of gate valves, globe valves, plug valves, ball valves, check valves and butterfly valves whose opening and closing parts are non-metallic seals and metal seals. Other valves can also refer to the two standards for pressure test according to the product standards. At present, steel valves are generally pressure tested according to JB/T 9092 standard. Iron and copper valves and forgings and castings of valves shall be subjected to pressure test according to GB/T 13927.
Valves, forgings and castings referred to in the following standards are currently subjected to pressure test according to GB/T 13927.
1) GB/T 12232-2005 “General purpose flanged iron gate valves”.
2) GB/T 12233-2004 “General purpose valve iron globe valve and lifting check valve”.
3) GB/T 12238-1989 “General purpose flanged and clamp connection butterfly valves”.
4) GB/T 12228-2006 “General valve carbon steel forgings technical specifications”.
5) GB/T 12229-2005 “Specification for carbon steel castings for general purpose valves”.
6) JB/T 9094-1999 “Technical requirements for emergency shut-off valves for LIQUEFIED petroleum gas equipment”.
Valves referred to in the following standards shall be pressure tested according to JB/T 9092-1999 “Testing and Inspection of Valves”.
1) GB/T 12224-2005 “Steel valves general requirements”.
2) GB/T 12234-1989 “General purpose flanged and butt welded steel gate valves”.
3) GB/T 12235-1989 “General purpose flanged steel globe valves and lift check valves”.
4) GB/T 12236-1989 “Steel swing check valves for general purpose”.
5) GB/T 12237-1989 “General purpose flanged and butt-welded steel ball valve”.
6) JB/T 7746-2006 “Compact Steel valve”
In JB/T 9092-1999 and API 598-2004, the valve pressure test includes the following items: shell test; Upper seal test; Low pressure seal test; High pressure seal test.
See Table 5-24 for the pressure test items of valves.
Table 5-24 Pressure test items of various valves
① Even if the valve is qualified in the sealing test, it is not allowed to disassemble and install the packing gland or replace the packing under pressure of the valve.
The valve with upper sealing performance requirements must be carried out on the sealing test.
(3) With the consent of the buyer, the valve manufacturer may substitute the hydrostatic pressure test for the low pressure gas seal test.
In GB/T 13927 and ISO 5208 standards, the valve pressure test includes: shell test; Sealing test (ISO 5208 does not have this test item); Seal test.
Although GB/T 13927 and ISO 5208 standards do not clearly divide the sealing test into low pressure sealing test and high pressure sealing test, but in a certain nominal size and nominal pressure range, available gas medium for low pressure sealing test, but also in the whole nominal size and nominal pressure range with liquid medium for high pressure sealing test.
GB/T 13927 and ISO 5208 stipulate that under the smaller nominal size (DN≤50mm) and nominal pressure (PN≤ 0.5mpa), 0.5 ~ 0.7mpa gas medium is allowed to be used for shell test. JB/T 9092 and API 598 specify that the material shall be subjected to shell test at 1.5 times the rated pressure at 38℃.
In addition, there are also obvious differences between THE provisions of GB/T 13927 and JB/T 9092 in terms of short test duration and allowable leakage.
ISO 5208 and API 598 are currently the most international valve pressure test standards, many countries are referring to these two standards to develop their own standards. The following is an introduction and comparison of the main standards of pressure test at home and abroad according to the classification of pressure test items.
1 2 3 4 5 6 7 8 Valve electric device related standards are introduced in the design, manufacture and test of valve electric device to regulate the above work. Common standard names and codes are listed below as indexes for easy lookup. In addition, the listed standard content will be briefly introduced.
▲JB/T8528-1997 General valve electric device specification
It is the standard for valve electric devices, which came into effect in 1998-01-01. It is a revision of ZBJ16002-87 technical Specifications for electric valves. According to the design, test, inspection and application practice of electric devices in recent years, the standard has revised the working environment temperature, noise index, starting torque, maximum torque, control torque, control speed and test method of ZBJ16002-87. Its implementation will replace ZBJ16002-87.
Our company is the main drafting unit of this standard
▲GB12222-89 Multi-turn valve drive device connection
The standard is equivalent to the international standard ISO5210/1 ~ 5210/3-1982 “Multi-turn valve Driving Device connection”. It provides the connecting dimensions of the multi-turn valve drive device and the valve and the dimensions of the drive parts, as well as the reference values of torque and axial thrust. This standard applies to dimensions of connection of valve actuation devices to valves for gate, globe, throttle and diaphragm valves.
At present, the connection size and type of products of some electric device manufacturers in the world are the same as the standard. The connection size of SMC, SCD and BA products of our company conforms to this standard.
▲GB12223-89 Partial rotary valve drive device connection
The standard is equivalent to the international standard ISO5211/1 ~ 5211/3-1982 “Partial rotary valve electric Device connection”. It provides the connection size of the driving device and the valve of part of the rotary valve and the size of the driving parts, as well as the reference value of the torque. This standard applies to dimensions of connection between valve drives and valves for ball, butterfly and plug valves.
The connection size of HBC series products of our company is different from this standard, but we can provide SMC/HBC partial rotary products that meet the standard size according to user requirements, and the connection size of SMC/JA products and valves can also be provided according to this standard.
▲JB/T8862-2000 Valve electric device life test specification
The standard specifies the test requirements, test items and test methods of life test of valve electric device. The life test of valve electric device type test is still carried out according to this standard. Jbz247-85 is one of the reference standards of JB/T8528-1997 “Technical conditions for Electric Valves”.
▲JB/TQ53168-99 multi-turn valve electric device product quality classification
The standard specifies the product quality grade, test method and sampling leveling method of multi-turn valve electric device. The indexes of torque repetition accuracy, life test, noise and other items are stipulated, and the quality grades of qualified products, first-class products and excellent products are stipulated.
▲JB2195-77YDF series three-phase asynchronous motors for electric valves
This standard is the first one in China on valve motor standard, it specifies the valve motor technical requirements, connection parameters, acceptance rules, etc. Limitorque motors used by SMC series have relatively higher technical parameters than YDF series (that is, SMC series does not use YDF motors), so this standard has been revised.
Post time: Jun-22-2022
