When the pressure is low, the flange thickness is small, the cost increase is not much, the heat stress generated when heating and cooling is small, rely on bolt tightening force and gasket easy to achieve sealing. It is more convenient to repair or replace valve when flange connection is used. The working pressure of ZECO high pressure gate valve is very high. If the flange is still connected with the pipe, the flange thickness is very large. Not only the cost of flange and bolt is obviously increased, but also the thermal stress generated by heating and cooling is very large. As the pressure increases, the working medium temperature also rises, the bolt in the high temperature long-term work appears the relaxation, reduces the flange to the gasket pressure easy to cause the gasket leakage. Leakage a third occurred not only developed quickly, and high-speed leakage of the medium is easy to blow out of the flange sealing surface perforating groove, repair is more difficult. If the valve and pipe are welded, the weight and cost are greatly reduced, the thermal stress during heating and cooling is significantly reduced, the sealing performance is greatly improved, and once leakage occurs, it is easy to deal with.
1. ZECO high pressure gate valve usually adopts VT (visual inspection) for welded products to check for obvious welding defects, such as cracks, edging, welding burps, molding defects, burning-through, spattering, etc.After passing the most basic visual inspection, PT is used to check whether there are cracks in the sealing surface surfacing and to test the hardness of the sealing surface;
2. The stem nut of ZECO high pressure gate valve is replaceable in line;
3. The backseat of ZECO high pressure gate valve is designed to relieve back pressure on the stem packing when fully seated;
4. The seat rings of ZECO high pressure gate valve are seal welded to provide a bubble tight joint.
ASTM A217 WC9
ASTM A182 F22 + STL
ASTM A217 WC9 + STL
ASTM A276 420
Graphite + SS316
ASTM A193 B16
ASTM A194 4
ASTM A217 WC9
ASTM A182 F6a