Technical Specification of Globe Stop Valves and Gate Valves
Electric power industry standard of the People's Republic of DL/T 531-94 power cut-off valve gate technology of high temperature and high pressure condition
1994-03-18 power industry of the People's Republic of 1994-10-01 approval
1 subject content and the applicable scope
This standard stimulates the power with high temperature and high pressure cut-off valve, gate valve classification and product quality requirements. This standard applies to nominal pressure for 20, 25, pN 32MPa, working temperature is equal to or lower than 425 ° c, Work stress p for 10, 14, 17MPa, working temperature for 510, 5.4, 57 degrees Celsius, Working medium for water and steam globe valves, gate valves.
2 reference standard
JB 4018 power valve model establishment method
ZBJ 98015 pressure casting technology conditions
GB 12231 valve castings quality requirements. Appearance
JB 2633 boiler forging technology conditions
GB 1176 casting of copper alloy technical conditions
GB 699 quality carbon steel technology conditions
GB 3,077 alloy steel and technical conditions
Carbon steel castings, classification and GB 979 technical conditions
GB 4981 industrial valves pressure test
GB 6414 casting dimension tolerance
GB 1804 appying the limit not note tolerances size deviation
GB 3595 power valve manufacturing technology conditions
X-ray photography and 5677 GB casting film classification method
GB 7233 castings quality rating method of ultrasonic testing and
GB 9443 castings quality rating method and infiltration testing
GB 9444 castings quality inspection and magnetic powder rating method
SDB of conten DZ series valve electric actuator
SDZ packaging technical conditions
3 terms
Globe valve disc stem drive from the seat sealing (for) axis movement of the valve,
Gate valves, gate) by (on-off valve stem drive along the valve seal for lifting movement
Manual cut-off valve, gate valve, by the handwheel, impact handwheels or gear rotating drive cut-off valve, gate valve,
Globe valves, gate valves, electric driven by electric device globe valves, gate valves.
5.7.1 The depth of the stuffing box for stem diameter of 2 times, when the stem diameter, and above 64mm 110mm for most depth.
5.7.2 inner pressure seal structure, the valve from the packing should adopt flexible graphite packing metal spiral wound gaskets without connectors.
5.8 handwheel
With the operation of the valve handwheel clockwise, is close, but must be written on the handwheel.
5.9 electric device
Motorized valve configuration of electric equipment should be consistent with the valve series of electric equipment DZ.
5.10 assembly basic requirements
5.10.1all the assembly parts and components (including out purchased parts, outsourcing) certificate and sign must hold.
5.10.2 The main parts with size and roughness should be inspected and optimizing
5.10.3 parts assembly and friction surface may affect performance scratches.
5.10.4all the assembly parts and components (including out purchased parts, outsourcing) may have burr, rust and processing surface bruising, visual qualified, the spectrum, conducted only after inspection.
5.10.5After assembly shall be tighten fasteners. Fasteners assembly, Screw on wire should pay paint heat buckle fat.
5.10.6manual valve, the valve stem lifting process shall not have card acerbity phenomenon, feel even.
5.10.7electric valves equipped with after the electric device should be adjusted to the switch with the valve is fully open and closed positions synchronization condition. Globe valves are close to torque protection device. Manual and electric change rotation handwheel. Hand induction
5.10.8 assembly, when valve closed, its gate valve should be higher than the center, the center for single disc sealing seat width of 2/3, Double disc sealing for seat width 1/2.
5.11 derusting, paint
5.11.1 derusting, paint should be in the hydrostatic test, and after the body cavity clean stain.
5.11.2 valve surface coating corrosion appearance processing, surface processing fat lacquer.
5.11.3before the paint on the surface must be clean, besmear after a primer, besmear again turns a layer of paint.
6 test method
6.1 material experiment
The valve shall conform to the use of material in the experiment. 5.2.2
6.2 hydrostatic test
The hydrostatic test valves according to the provisions of 8.4, shell strength test and sealing, seal test.
6.3 type
6.3.1
One of the following conditions 6.3.1, for the type:
A new product trial,
B. when old product structure, materials, technology has greatly change,
C. superior quality supervision organization for testing requirements.
6.3.2 type includes the following content:
A. this chapter and 6.1 and 6.2 article including experiment content,
B. the new material or material composition, technology has greatly changed, must do metallographic analysis,
C. shell, when the hydrostatic test stress analysis,
D. static life test,
E. resistance test.
G. sign position and its parameters according to the provisions 9.1.1 correctly, According to the 9.1.2 body symbol clause correctly,
H. valve factory before installation, users without disassembly check in half a year after the installation, internal quality problems by manufacturer, responsible for repair or replacement.
The inspection of products and complete inspection data correctly, prepare production Numbers, quality inspection department issued the certificate of product quality, with products to customers.
9 marks, packaging, transportation and storage
9.1 marks
9.1.1 signs should have the following:
A. factory name,
B. product name and model,
C: product main parameters of the nominal pressure, temperature, pressure, and limit the working medium type, the maximum torque,
D. manufacturing date and production batch,
E. quality grade mark.
9.1.2body must be cast out the following content:
A. material code,
B. the nominal pressure (or working temperature working pressure),
C; the nominal diameter.
D. the flow direction of medium,
E. valve furnace.
9.2 packing, transportation and keeping
9.2.1 packing, transportation and storage process, the valve should be closed. In the antirust processing and paint, to cover both close, prevent dirt, water invasion.
9.2.2packing products, should be fixed in the box, are not allowed to make the handwheel or electric equipment support valve its own weight, to ensure the transport from damage.
9.2.3 each valve in the factory with the technical documents shall be sealed and can moistureproof, waterproof in bags:
A. product quality certificate,
B. the major parts of the test report;,
C. product specifications (total assembly drawing, delicate),
D. packing list.
9.2.4 products should be stored in dry places are not allowed to open or products will be piled up.