What is the production standard for each part of the electric ball valve in the waterworks. Every part of the electric ball valve, from the whole electric ball valve, flange, welded pipe, seal ring, etc., has a basis and standard. Many customers do not know which basis and standard to follow when accepting. At this time, they should have a headache. How to accept? Where is the acceptance without standards? If the products produced by the electric ball valve manufacturers can stand the test, they must provide the customers with the basis standards for acceptance. Now let's see what the basis standards are for each part.
Production standards for all parts of double flange electric ball valve:
1. For double flange limit electric ball valve (compensation joint) with nominal diameter ≤ 400mm, the cylinder of its limit stub and stub flange should be seamless steel pipe, and the quality should meet the requirements of GB/T8168 or GB/T14976. For the cylinder with nominal diameter ≥ 450mm, the above cylinder should be welded with steel plate reel, and the quality of welded pipe should meet the provisions of GB/T9711.2.
2. The double flange limit electric ball valve consists of a limit stub, and the cylinder quality of the stub flange shall meet the requirements of ISO2531.
3. Carbon steel fasteners for double flange limit electric ball valves shall be hot-dip galvanized, and the coating thickness shall comply with GB/T13912.
4. The surface of the parts of the double flange limit electric ball valve shall be free of cracks, scars, folds, layers and other defects, and shall be free of scratches, grooves or obvious depressions caused by collision.
5. Limit screw: marine gland loose sleeve electric ball valve shall be equipped with limit screw.
6. Surface protection: For carbon steel and nodular cast iron electric ball valves used for corrosive media such as seawater, the surface of the valve should be coated with plastic or hot galvanized or nickel phosphorus coating, which should meet the requirements of GB/T13912, GB/T13913 CJ/T120 respectively. For carbon steel and nodular cast iron electric ball valves used for lubricating oil and other media, the surface of the valve should be coated with epoxy coating or coated with antirust paint. 7. Strength: The strength of the body of the double flange limit electric ball valve shall be able to withstand the pressure of 1.5 times the nominal pressure and hold it for 5min without leakage and obvious plastic deformation.
8. Tightness: The sealing pair of double flange limit electric ball valve shall be able to withstand the pressure of 1.25 times the nominal pressure for 5min without leakage.