Sealability and strength properties is the character of the most basic and most important for all valves.
The sealing valve seal can be separated into internal and external seals. Its front means sealing between the clack valve and seat.
If sealability is not good or not power-intensive, the parts can be destroyed. Thus, it would result in economic losses at different levels, such as the transport of toxic liquids, explosive or corrosive.
Generally, valves for low pressure and non-corrosive liquids made of cast iron or cast copper and the same properties having the ace valve. High or medium-pressure cast steel or forged steel.