1 General Requirements
1.1 specifications and types of valves, pipes should be in accordance with the requirements of design documents.
1.2 The valve should be specified based on Model GB code requirements. If the enterprise standard models should be specified instructions.
1.3 valve working pressure of the working pressure ≥ pipeline, prices will not be affected under the premise of the valve can withstand working pressure pipe should be larger than the actual pressure of work; valve closed condition either side should be able to withstand 1.1 times the work pressure valve without leakage; valve open condition, valve body should be able to withstand twice the pressure valve work requirements.
1.4 valve manufacturing standards, should indicate the basis of the national standard code, if the enterprise standards, procurement contract shall be accompanied by a business document.
2 valve material
2.1 valve material, gray cast iron pipe as a result of the progressive is not recommended the use of body-based material should be ductile iron, and indicate the grade and the actual casting of the physical and chemical test data.
2.2 stem material to stainless steel stem (2CR13), large diameter valves should be stainless steel stem inlay package.
2.3 nut material, the use of cast brass or cast aluminum bronze, and the hardness and strength are greater than the stem.
Stem 2.4 bushing material, its hardness and strength shall be not more than stem and immersed in water conditions with the stem, not the formation of electrochemical corrosion body.
2.5 sealing surface of the material
① different types of valves, sealing methods and materials require different;
② ordinary wedge gate valve,铜环materials, fixation methods, grinding should be that way;
③ soft-sealing valve, the valve plate lining material detection and health physical and chemical data;
④ butterfly valve body shall identify the material on the sealing surface and sealing surface material butterflies board; their physical and chemical test data, especially the health requirements of rubber, anti-aging properties, wear resistance; usually small eyes and ternary rubber B propylene rubber, etc., is strictly prohibited to use reclaimed rubber doped.
2.6-axis fill valve
① As the pipe network of valves, are usually not frequent sluicegate asked not to fill in a few years the activities do not fill the aging and long-term effects remain sealed;
② fill valve shaft hoist should bear frequent, the sealing effect of the good;
③ In view of the above requirements, fill valve axis does not strive for life or not to replace more than a decade;
④ For replacement of packing, valve design should be considered to have the situation under pressure to replace measures.
3? Speed gearbox?
Box 3.1 and outside the anti-corrosion materials and principles with Valve.
Box 3.2 Measures should be sealed, after the tank assembly to be capable of sustaining the status of three meters of water immersion.
Box 3.3 on the hoist limit devices, the adjustment nut should be箱体内.
3.4 Drive structural design reasonable, when the gate valve axis rotation can only be driven, not make it up and down a rocky ledge, moderate occlusal transmission components, with no separation of the load when the sliding headstock.
3.5 Transmission Box Office with the valve shaft seal without leakage can not be connected whole.
3.6箱体内no debris, gear grease occlusal protection shall be provided.
4? Valve operation of institutions
4.1 The operation of the gate valve direction shall be clockwise to close.
4.2 As the pipe network of valves, often manual hoist, hoist a few should not be too much change, that is, large-diameter valves to be within the 200-600.
4.3 In order to facilitate a person's gate operation, under pressure in the plumbing, the biggest gate for the moment wish to 240m-m.
4.4 gate valve operation should be the client side mortise and size standardization, and for the ground so that people can be directly from the ground operation. Roulette with the valve does not apply to underground pipeline network
4.5 shows the extent of the valve gate plate
① scale degree of the valve gate line, should be sealed with casting or conversion in the gearbox after the show the direction of the shell on the plate, all for the ground, brush on the phosphor calibration line in order to show that eye-catching;
② instructions set the needle in the management of the material circumstances better stainless steel plate can be used, otherwise the plate for the painting, not to use the production of aluminum skin;
③ instructions set the needle eye-catching, fixed solid, accurate adjustment once the gate should be locked in order to rivet.
4.6 If the valve buried deeper, operation and display disk ≥ 1.5m distance from the ground, the pole should have additional facilities, and fixed firmly stabilized so that people from the observation and operation of the ground. In other words, the pipe network in the gate valve operation, not to go down operations.
5? Valve performance testing?
Valve of a 5.1 volume manufacturing specifications, the agency should be entrusted to the authority of the following performance tests:
① pressure valve in the situation of workers of the headstock under the moment;
② In the situation of workers under pressure to ensure tight closure of the valve gate number of a row;
③ valve in the pipe under the condition of the detection of flow resistance coefficient.
5.2 Valves should be carried out in the factory following the detection of
① Open the valve in the circumstances, the valve body should be subject to twice the pressure of work pressure detection;
② valve closing conditions, on both sides of 1.1 times, respectively, the valve works under pressure, no leakage; but metal sealed butterfly valve, leakage is no greater than the value of the related requirements.
6? Valve internal and external corrosion
6.1 Body (including the variable-speed transmission box) inside and outside, first sand shot blasting rust clearance to electrostatic spraying epoxy resin powder non-toxic, more than 0.3mm thickness. Spray large non-toxic epoxy electrostatic valve difficulties, they should also Brush, spray similar to the non-toxic epoxy paint.
6.2 Body as well as all parts of the valve all-round anti-corrosion requirements, on the one hand immersed in water will not rust, between two non-metal electrochemical corrosion; two aspects to enable a smooth surface to reduce water resistance.
6.3 The valve body or anti-corrosion epoxy resin paint health requirements, the authority should have the corresponding organs of the testing report. Physical properties of the chemical should be in line with the relevant requirements.
7? Valve packing transport
7.1 on both sides of the valve should be closed solid light blocking plate.
7.2, the small-caliber valve should be bundled straw, and container transport is appropriate.
7.3 Summary of large diameter valves are also the framework of solid wood packing spaces in order to avoid impact damage during transport.
8? Valve factory brochure
Valve equipment in the factory specification should be marked with the following data:
Valve specifications; models; work pressure; manufacturing standards; Body material; stem material; seal material; valve shaft packing material; stem sleeve material; internal and external anti-corrosion material; direction start operation; rotation; work under pressure Kai Moment closure; Make factory; factory date; factory number; weight; connecting flange of the aperture, hole number, the Center Distance; with icons indicating the way the overall length, width and height dimensions of the control; valve flow resistance coefficient ; effective number headstock; valve factory testing and installation of the relevant data, such as the maintenance of attention.