Blowoff Valves 

Flowserve Edward manufactures the valves sold for blowoff service to comply with all ASME Boiler code criteria for valves used in these applications.

The blowoff valves are designed for applications requiring intermittent operation in order to remove accumulated sediment from equipment, piping or to lower boiler water level in a rapid manner. 

Requirements and limitations on Blowoff Valves:

• Size restricted from 1"-2.5"
• Prohibited use of T-pattern globe valves 
• Mandate the use of two valves in series on boilers operating at pressure greater than 100 psig

Blowdown Valves

Blowdown Valves are designed for continuous use to control the concentration of dissolved solids in boiler water. There are no restrictions on the valve body configuration and only one valve is required. However, the valve must have a valve position indicator accurate to within 0.1 turn of the handwheel. 

Blowdown valves for intermittent use must meet the requirements and limitations of Blowoff valves described above. Reference ASME B31.1, section one, Paragraph 122.1.4 and 122.1.7.