The necessary technical factors to consider in purchasing anti-corrosion solenoid valve valve list the necessary technology to purchase valve

The necessary technical factors to consider in purchasing anti-corrosion solenoid valve valve list the necessary technology to purchase valve

Solenoid valve procurement only clear specifications, categories, working pressure to meet the procurement requirements of the practice, in the current market economic environment is not perfect. Because valve manufacturers in order to product competition, they are in the concept of unified valve design, different innovation, the formation of their own enterprise standards and product personality. Therefore, it is very necessary to put forward the technical requirements in detail when purchasing valves and reach a consensus through coordination with manufacturers as an attachment to the valve purchase contract. 1. General requirements 1.1BURKERT solenoid valve Valve specifications and categories shall comply with the requirements of pipeline design documents. 1.2BURKERT solenoid valve valve type shall be indicated according to the national standard number requirements. If the enterprise standard, should indicate the relevant description of the model. 1.3 The working pressure of BURKERT solenoid valve shall be ¡Ý the working pressure of the pipeline. Under the premise of not affecting the price, the working pressure that the valve can bear shall be greater than the actual working pressure of the pipeline; Any side of the closed valve should be able to withstand 1.1 times the valve pressure value without leakage; BURKERT solenoid valve open condition, the valve body should be able to withstand the requirements of two times the valve pressure. 1.4BURKERT solenoid valve manufacturing standards, should indicate the basis of the national standard number, if the enterprise standard, the procurement contract should be attached to the enterprise documents. 2.1 The body material of the BURKERT solenoid valve should be mainly ductile iron, and indicate the brand and the actual physical and chemical test data of the cast iron. 2.2BURKERT solenoid valve stem material, strive to stainless steel stem (2CR13), large diameter valves should also be stainless steel clad stem. 2.3 The nut is made of cast aluminum brass or cast aluminum bronze, and the hardness and strength are greater than the valve stem. 2.4BURKERT solenoid valve stem bushing material, its hardness and strength shall not be greater than the stem, and under the condition of water immersion with the stem, valve body no electrochemical corrosion. 2.5 Material of sealing surface: (1) Different types of valves, sealing methods and material requirements; ¢Ú Common wedge gate valve, copper ring material, fixing way, grinding way should be described; ¢Û Physical, chemical and health test data of soft seal gate valve and valve plate lining rubber material; BURKERT solenoid valve shall indicate the sealing surface material on the valve body and the sealing surface material on the butterfly plate; Their physical and chemical test data, especially rubber health requirements, aging resistance, wear resistance; Usually use butadiene rubber and EPDM rubber, it is strictly prohibited to mix with recycled rubber. 2.6BURKERT solenoid valve shaft packing: (1) Because the valve in the pipe network is usually opened and closed infrequently, the packing is required to be inactive in several years, the packing is not aging, and the sealing effect is maintained for a long time; (2) Valve shaft packing should also withstand frequent opening and closing, sealing effect is good; (3) In view of the above requirements, the valve shaft packing should not be replaced for life or more than 10 years; ¢Ü If the packing needs to be replaced, the valve design should consider the replacement measures under the condition of water pressure. 3. Variable speed transmission box 3.1 Box material and internal and external anticorrosion requirements are consistent with the valve body principle. 3.2 The box body should be sealed and can withstand soaking of 3m water column after assembly. 3.3 The adjusting nuts of the opening and closing limit device on the box should be located inside or outside the box, but only the first tool can be used for operation. 3.4 Reasonable transmission structure design, opening and closing can only drive the valve shaft rotation, do not make it move up and down, moderate transmission parts bite, do not produce load when opening and closing separation slip. 3.5 The sealing place between the gearbox and the valve shaft shall not be connected into a leak-free whole, otherwise reliable measures should be taken to prevent serial leakage. 3.6 There is no sundry matter in the box, and the gear occlusal part should be protected by grease. 4. Operating mechanism of BURKERT solenoid valve 4.1 Opening and closing directions of BURKERT solenoid valve during operation shall be closed clockwise. 4.2 Because the valves in the pipe network are often opened and closed manually, the opening and closing revolutions should not be too much, even the large diameter valves should also be within 200-600 revolutions. 4.3 In order to facilitate one person’s opening and closing operation, under the condition of plumber pressure, the relatively large opening and closing torque should be 240N-m. 4.4BURKERT solenoid valve opening and closing operation end shall be square tenon, standardized size, and face the ground, so that people can operate directly from the ground. The valve with wheel is not suitable for underground pipe network. 4.5BURKERT solenoid valve opening and closing degree display plate: (1) The scale line of the valve opening and closing degree should be cast on the gearbox cover or the shell of the display plate after the conversion direction, all facing the ground, the scale line is brush with phosphor, to show eye-catching; (2) The material of the indicator plate needle can be used in the case of better management of stainless steel plate, otherwise painted steel plate, do not use aluminum skin production; The indicator disk needle eye-catching, fixed firmly, once the opening and closing adjustment is accurate, should be locked with rivet. 4.6 If BURKERT solenoid valve is buried deep and the distance between operating mechanism and display panel from the ground is more than 1.5m, extension rod facilities should be provided and fixed firmly for people to observe and operate from the ground. That is to say, the valve opening and closing operation in the pipe network is not suitable for well operation.
At present, the valve production industry is in a very favorable period of development. This is mainly due to the sustained and steady development of the national economy and the gradual expansion of investment in fixed assets. Domestic valve products are still a large number of imports, and domestic valves mostly belong to low value-added, labor-intensive products, few with international level. According to relevant departmental statistics, our country annual market turnover of valve up to 50 billion yuan or so, including more than 10 billion yuan market is occupied by foreign valve enterprises.
At present, the valve production industry is in a very favorable period of development. This is mainly due to the sustained and steady development of the national economy and the gradual expansion of investment in fixed assets. Domestic valve products are still a large number of imports, and domestic valves mostly belong to low value-added, labor-intensive products, few with international level. According to relevant departmental statistics, our country annual market turnover of valve up to 50 billion yuan or so, including more than 10 billion yuan market is occupied by foreign valve enterprises. Inside and outside the valve body (including variable speed transmission box), the first thing should be shot blasting sand cleaning and rust removal, and strive to electrostatic spraying powder non-toxic epoxy resin, thickness of more than 0.3mm. When electrostatic spraying non-toxic epoxy resin is difficult for oversized valves, similar non-toxic epoxy paint should also be brushed and sprayed. Valve body internal and valve plate each part of the requirements of anti-corrosion, on the one hand, immersion in water will not rust, between the two metals do not produce electrochemical corrosion; Two aspects of smooth surface to reduce water resistance. The sanitary requirements of the anticorrosive epoxy resin or paint in the valve body shall be tested by the corresponding organ. Chemical and physical properties should also meet the relevant requirements. Both sides of the valve should be fixed with light plugging plates.
Medium and small diameter valves should be tied with straw ropes and transported in containers. Large diameter valves also have simple wooden frame solid packaging, so as to avoid damage during transportation. Valve is equipment, in the factory manual should be marked with the following data: valve specifications; Model number; Working pressure; Manufacturing standards; Valve body material; Stem material; Sealing material; Valve shaft packing material; Valve stem sleeve material; Internal and external anticorrosive material; Operation start direction; Revolutions; Opening and closing moment under working pressure; The name of the manufacturer; Date of delivery; Factory number; Weight; Connecting flange aperture, hole number, center hole distance; The control dimensions of overall length, width and height are indicated in graphic form; Valve flow resistance coefficient; Effective opening and closing times; Valve factory test data and installation, maintenance precautions, etc.