Domestic valve, koso valve is better, its general and popular use effect is also very good, in domestic production of atmospheric valve (below 600 pounds), high-pressure valve needs to be imported.
Compared with foreign brands, it is still a little worse, such as Fisher, which is not in the same grade. The purchase of shut-off valve is done according to the process conditions to determine whether an inlet valve is required. For general applications, the Koso valve can be used. Fisher, FLOWSEWA and Masoneilan are better for more severe conditions, but Masoneilan is mainly used in severe conditions.
Fisher mainly produces regulating valves, and the imported Fisher valves are basically high-end products with high prices. In terms of on-off valves, good brands include NELES, TYCO, FLOMSERVER, etc.
There are two types of valves used in the production line of our installation: Koso and Fisher. The small-diameter regulating valve uses fisher, and the large-diameter butterfly valve and sleeve valve use koso. First of all, consider the cost-effectiveness. The price of fisher valves above DN400 for large-diameter butterfly valves is too expensive, and it is relatively unnecessary. The 600S of the koso valve can meet the process needs; if the sealing requirements are higher, the 710E model ( High price and long processing cycle);
If you use the fisher, the price is 10 times higher than that of the KOSO 710E of the same caliber. We use fisher valve positioner equipped with DVC2000 for small-diameter valves, which are very convenient to use and adjust, fully intelligent, and only need a few seconds to adjust; now Koso small-diameter valves are equipped with Siemens valve positioners. The operation is also relatively stable, and the problem of long-term use is not big; the selection of the remaining positioners and valves depends on the supply cycle and price comparison of each brand.
The quality of the koso control valve is good, and it can meet the general working conditions. For the small flow regulating valve, Meloniilan is the best, and the cam deflection valve used in severe working conditions is also the best of Meloniilan. The on-off valve mainly depends on the material of the valve seat, the hardness and the hardness of the valve stem. The better ones are Flowserve, Tektronix and Metso.
The brand valves mentioned above can be matched with koso positioners. As long as the working conditions are not very severe, koso positioners can meet user applications.
