The main difference between normal valves and bellows seal valve is the stem seal. Bellows seal valves adopt bellows as stem seal to replace packing which is used in normal valves. The bellows are welded to connect the bonnet. And bellows seal valves can also use packing seal as secondary stem seal to achieve double seal.

When there are very strict stem seal requirements in some special applications like thermal oil system, steam system and dangerous medium with flammability, poisonousness, radioactivity and easy to be exploded, normal valves can't meet the requirements, then bellows seal valves are used to avoid leakage of medium and energy from stem to ensure the safety, reduce maintenance cost and improve efficiency of energy use.

There are customized bellows seal valves with extended stem or special design to be suitable for flammable, explosive and poisonous medium like chlorine. The bellows can be isolated to avoid corrosion and abrasion caused by working medium for longer working life.

There are bellows seal gate valves, bellows seal globe valves and bellows seal Y type globe valves. The bellows seal valves can be produced according to ANST or DIN standards.

The body of bellows seal valves can be casted or forged and the materials are suitable for low temperature and high temperature working conditions.

YFL bellows seal valves are widely used for power stations, waste gas purification plant, natural gas, high vacuum applications, ammonia, hot water system, refrigeration system, heating equipments, steam system, thermal oil system, chemical projects and nuclear industry etc.

Should any question, please don't hesitate to contact YFL engineers at sales@YFLvalve.com to solve problems, improve process, reduce maintenance cost and create values.