Water supply and drainage by hydraulic slowly-closing check technical
1 scope
This standard stimulates the water using hydraulic slowly-closing check (hereinafter referred to as the hydraulic slowly-closing check) product classification, requirements, experiment method, inspection rule, mark, packing, transportation and storage of basic requirements.
This standard applies to PN than nominal pressure, nominal diameter 4.0 MPa 4000mm acuities DN, working temperature is not more than 80 ° c, work for drinking water, water, medium water, sewage, industrial water and other corrosive medium flange connection of hydraulic slowly-closing check valves.
2 reference standard
The following standards contain provision which, through reference in this text, constitute provisions of this standard. At time of publication, the editions indicated were valid, all standards are revised, the use of the standard of the parties should use the following standards out the possibility of the latest version.
GB/T 9112-1988 steel flange type
GB/T 12220-1989 generic valve symbol
GB/T 12221-1989 flange metal valve structure length
GB/T 12236-1989 generic valve steel swing check valves
OB sign/T 12238-1989 common valve flange connection and clip
GB/T 13927-1992 general valve pressure test
CB/T 13932-1992 general valve iron swing check valves
CB/T 17241.6 a whole cast iron pipe flanges, 1998
GB/T 17241.7-1998 iron pipe flanges technical conditions
JB/T 5296-1991 generic valve flow coefficient and the resistance coefficient of test method
JB/T 7748-1995 and check valve. Cleanness
JB/T 7928-1995 common valve supply requirements
3 definition
This standard adopts the following definitions.
The hydraulic slowly-closing check valves
Disc, the butterfly plate with or without the help of medium, medium, and automatic stop upstream slowly closing device operates, is able to prevent destructive water hammer a valve.
4 classification
4.1 product classification
According to the structure is divided into: 4.4.1
A) hydraulic slowly-closing swing check valves,
B) butterfly double disc hydraulic slowly-closing check valve,
C) wing hydraulic slowly-closing check valves
4.1.2 press hydraulic slowly-closing device using damping medium is divided into:
A) pressure hydraulic slowly-closing check: JiXieYou using damping medium,
B) pressure hydraulic slowly-closing check valve, Damping medium with water.
4.1.3 press hydraulic slowly-closing device form is divided into:
A) since damping hydraulic slowly-closing check: hydraulic slowly-closing device installed in the body, as damping medium pipeline medium,
B) the damping hydraulic slowly-closing check: hydraulic slowly-closing device installed in the pipeline, medium body as damping medium,
C) fluid control wing hydraulic slowly-closing check (hereinafter referred to as the hydraulic controlled wing check) : by hydraulic device control level close to the work of the state, the piston unit weight control hydraulic slowly-closing ze-cai-er-yong potential automatic phases according to close the valve, cut-off gentle closed check two functions, can realize the valve control.
4.2 structure
The hydraulic slowly-closing check valve structure form
5 requirements
5.1 flange hydraulic slowly-closing check valve structure length of GB/T 12221 shall be prescribed by the user or agreement, wing check valve opens, the butterfly plate outstretched length shall not be affected. Flange size, seal 5.2 and type of GB/T should comply with the 17241.6, GB/T 17241.7 or GB/T 9112 regulation. The minimum thickness of 5.3 body should comply with the GB/T 12236, GB/T or GB/T 13932 12238. 5.4 materials 5.4.1 hydraulic slowly-closing check valve body and bonnet, disc (butterfly plate), the major parts material valve spindle etc should be GB/T 12236, GB/T or GB/T 13932 12238. 5.4.2 slowly closing device damping materials should satisfy the piston cylinder pressure requirements, piston, piston rod surface chromium plating, should be adopted, the piston ring piston oil resistant materials butadiene acrylonitrile rubber, etc. 5.4.3 water hydraulic slowly-closing check valve body with inner cavity and other metal parts in contact with water using anti-corrosion coatings and rubber seals shall avirulent insipidity. 5.5 hydraulic slowly-closing check valve closure process shuts rapidly.can and ordered two stages, its hydraulic slowly-closing time can be adjusted. 5.6 hydraulic slowly-closing check valve non-return valve hydraulic slowly-closing opening of the piston is slowly closing out full length is adjustable. 5.7 hydraulic slowly-closing check valve non-return valve (butterfly plate) and should be no jam phenomenon. 5.8 The hydraulic slowly-closing piston must action is sensitive, damping when non-return valve (butterfly plate can be rapidly when opening) work out at a predetermined position, when non-return valve (butterfly plate) close to the hydraulic slowly-closing position can effective hydraulic slowly-closing role of damping device. Slowly closing capacity of the piston cylinder should be used with the regulator, etc, to avoid matching the damping piston cylinder and pipe pressure is too high, and achieve the goal can be mixed hammer away. 5.9The damping hydraulic slowly-closing check valve, the hydraulic controlled wing check valves should be attached to monitor hydraulic slowly-closing device of the medium level damped. 5.10 Since the damping hydraulic slowly-closing check valve does not allow the water containing solid particles, sewage and waste water directly into the hydraulic slowly-closing device, avoid jams or damage. 5.11 fluid control wing check valve, check valve hydraulic slowly-closing wing should not display correct net butterfly plate opening position indicator agency. 5.12 fluid control wing check valve should be installed hammer or accumulator as additional force source for power automatically close the valve. 5.13 slowly closing device related links, transmission and support a sufficient intensity and rigidity. 5.14 and hydraulic device: standard hydraulic parts and electric parts should choose reliable quality, good performance, long life, according to their respective products and relevant provisions of standard test, qualified rear can use. Hydraulic device assembly, should undertake various parameters adjustment and performance test, which accords with the valve hydraulic slowly-closing ", "the design requirements. 5.15Hydraulic slowly-closing stop-check valves external lacquer layer, colour and lustre should be uniform appearance --, flat, smooth and should not have scars, sagging, foaming and obvious crack defects.
6 test method
Use visual appearance, size 6.1 instances.some etc, the conventional test fixture.
General requirement testing 6.2
6.2.1 in shell, not allow to test before valve paint or using other prevent leakage of coating.
6.2.2 seal test before, should remove the oil seal surface to prevent scratch, allowed a layer of oil viscosity is not more than kerosene membrane.
6 2.3 test should be within the body cavity before clean. And out of the valve body cavity, test process, the gas valves may influence the results of force.
6.2.4 without special provisions, test at room temperature, medium for water purification test.
3 test program
Test items include:
A) shell test,
B) seal test,
C) the hydraulic slowly-closing device test,
D) stop the pump valve closed water hammer of peak and pump reversal speed tests,
E) valve resistance coefficient test.
6.4 shell test
6.4.1 shell test test pressure shall conform to the provisions of the table l.
6. 4. 2 test duration should comply with the GB/T 13927 return.
6.4.3 test methods and steps
Close the valve inlet and outlet, the valve is in full open state, in the casing (not installed internal parts) fill water, air, from the inlet pressure to test pressure, gradually in test duration, confined and body and valve is not visible in PE link, shell leakage (including body and bonnet joint) shall be structural damage.
6.5 seal test
6.5.1 seat tightness test pressure test according to the provisions in table 2.
6.5.2 test duration should conform to the provisions of GB/T 13927.
6.5. 3 testing methods and steps: disc (butterfly plate) in normal mode should be shut, from the outlet water) introduced testing medium (pressure to test pressure gradually, then check the sealing seal.
6.5.4 maximum allowable leakage shall conform to the provisions of GB/T 13927.
6.6 slowly closing device test
6 6.1 disc (butterfly plate) sensitivity test
In the racing without medium conditions, by hand or appliance will disc (up) to the butterfly plate, loosen the butterfly valve (after) can free to check, reciprocating three times, should comply with 5.7.
6.6.2 hydraulic slowly-closing opening experiment
Assembly good hydraulic slowly-closing check lumen filled with water, pressurized to 0.15 MPa, hydraulic slowly-closing piston can stretch, when all the work pressure, reciprocating 3 times, should comply with the regulations. 560
6 6.3 hydraulic slowly-closing time test
6.6.3.1 assembly good hydraulic slowly-closing check lumen filled with water, slow compression, adjust the throttle to 1.0 MPa, record the piston hydraulic slowly-closing time, hydraulic slowly-closing time return should be adjustable.
6.6.3.2 wing hydraulic slowly-closing check valve can be manually no-load conditions in the open and close, the simulation experiment conditions, adjusting hydraulic slowly-closing time requirements, which meet the actual condition and eliminate water hammer.
The hydraulic slowly-closing 6.6.4 damping piston cylinder test
6 6.4.1 commissioning, without load conditions, manual reciprocating movement above 5 times, flexible, no external leakage.
6 6.4.2 outside leakage in the nominal full load, make travel lives after action 20 times, check the piston seal, not a leak.
6 6.4.3 pressure test: the piston stroke ends in respectively, stop to the system pressure rated pressure, the pressure 2min 1.5 times, everywhere, not a leak.
6.6.4.4 full stroke inspection: the piston stroke ends to stop respectively, measuring the stroke length, should comply with the design requirements.
6.7 Stop the pump of valve closed water hammer peak and pumps speed tests reversal
6.7. 1 experimental device and instrumentation see appendix A (standard appendix).
6.7.2 test method
A) will test the check valve and other instruments according to annex a (standard annex), to install inside pump start-up pump, filled with water, open gate, slowly and gradually open check valve, when the pipe flow stabilized, came to a sudden stop, read the pipeline pump water pressure, with speed meter to measure pump hydraulic slowly-closing RPM, change the schedule and hydraulic slowly-closing device, and stable in the water flow, stop the pump, then again suddenly measuring pressure pump and pipeline in reverse.
1) are also available on the pump working site, actual operation test.
2) a large hydraulic slowly-closing check valve, used for complex terrain, pipeline etc should be long working conditions for practical operation zhuang pump closing valves test.
6.7.3 water hammer peak and pump via debugging of reverse speed: hydraulic slowly-closing check, can effectively reduce the pump water hammer, the instant water hammer pressure peak is not more than 1.5 times of the pipeline, the pump shall not exceed reverse speed approx.1.3 times of rated speed.
68 the resistance coefficient of testing
6.8. 1 resistance coefficient of test methods 5296 JB/T seen.
6.8.2 flow resistance coefficient value should be more than 0.6.
7 inspection rules
The hydraulic slowly-closing check valve factory inspection and testing into type test.
7.1 factory inspection
7.1.1 hydraulic slowly-closing check valve shall be subject to the inspection, the inspection department manufacturer with certificate of rear must leave the factory.
7.1.2 hydraulic slowly-closing stop-check valves should be driven platform inspection.
7.1.3 hydraulic slowly-closing check valve factory inspection items in a) for 6.3) a.
7.2 type test
7.2.1 one of following cases, shall conduct pilot test.
A) the new product trial finalize the appraisal,
B) design, craft, material, and may affect a major change in product performance,
C) the normal production, regular or accumulated some production should be periodically after an examination.
D) production half when production.
7.2.2 type inspection items for:
A) the label of a) huai 6.3 a e),
B) the standard technology requirements of all projects,
C) away clean degree examination should comply with the 7748 Chan JB/T.
7.2.3 type test is unqualified, unqualified products.
7.3 sampling method
7.3.1 types randomly factory inspection to the inspection departments of inventory or supply users without the use of the valve.
7.3.2 each -- a specification for each type of sample number and sampling minimum number shall conform to the provisions of the table 3.
When the user 7.3.3 to sampling, the number of sample by 3 limit, sampling number according to the provisions of the table and still.
For the entire series quality sections 7.3.4. Sampling inspection department according to situation when the series 2-3 typical test specifications for sampling, the number and sampling 7.3.2 shall conform to the provisions of the number.
8 marks, packaging, transportation and storage
8. 1: hydraulic slowly-closing check valve symbol of GB/T 12220 regulation.
820 hydraulic slowly-closing check valve in the packing, transportation should be released the hydraulic oil.
8.3 packing, transportation and storage shall conform to the provisions 7928 JB/T.
