When choosing a double disc wafer type check valve it is important to make a cost-benefit analysis of the specific system. Often focus is to reduce cost and at the same time obtain the lowest possible pressure loss. CI and DI is cheap material, we chose short face to face standard to make wafer pattern twin plate check valve for cost saving. Compact design with short face-to-face dimensions minimizes space requirements. CI is a good material choice in normal working conditions and low pressure.
Our dual plate check valves conform to all industry standards. API 594 dictates valve dimensions, including wall thickness, face-to-face dimensions and OD, so valves can replace any make of ANSI dual plate water check valve. WCB material is cheaper than CF8 and CF8M and has good welding performance which is suitable for the environment where valve seat surfacing is required. If the body seat and plate seat are required for surfacing, WCB material is a good choice.
Full rubber body dual plate flange check valves design with no external body penetrations eliminating the possibility of outside leakage. Because the body design with full rubber lined The elevated costs and continuous variation in the prices of prime materials used for castings of alloyed materials for corrosion resistance is motivation to look for alternatives more economical or other type of constructions. Dual plate flange type check valve with full rubber is good choose. By this application costs can be reduced between 15% and 35% of the total valve cost compared with the body completely in alloy.
Because of the flange dual plate check valve is covered with full rubber, the body material can be selected the lower price DI or WCB material, the total price is lower than AL-BRONZE or Duplex and Super Duplex Stainless Steel. Full rubber flange type dual plate check valve’s material is divided into two choices, NBR and EPDM. It is much easier to install between standard gaskets and line flanges, and therefore is more cost effective to install and to maintain.
A wafer-style butterfly valve is the most economical version and it is sandwiched between two pipe flanges. Easy installation, many connection options. Butterfly valves are used for on-off or modulating services and are popular due to their light weight, small installation footprint, lower costs, quick operation and availability in very large sizes. These valves can be operated by handles, gears or automatic actuators.
Butterfly valves possess many advantages over gate, globe, plug, and ball valves, especially for large valve applications. Savings in weight, space, and cost are the most obvious advantages. The maintenance costs are usually low Butterfly valves are especially well-suited for the handling of large flows of liquids or gases at relatively low pressures and for the handling of slurries or liquids with large amounts of suspended solids.
There are several types of end connections that allow for easy installation of these valves, but the most common are lug and wafer style, both fitting between flanges. Lug style butterfly valves are similar to 3-piece ball valves -they allow adjacent piping to be removed independently. This is achieved by using two different set of bolts, with each attaching the pipe flanges at either end of the valve body. With this connection to the valve, the ends of the pipe sections can be removed and replaced independently. Installation is also fool-proof as the number of lugs make centering the valves easy.