The 727 design features allow this valve to operate closer to set point than any other safety device, the option to use remote sense lines and the valves high capacity means that this valve is used where others cannot perform. The valves are frequently installed in severe service, with less than ideal inlet piping arrangements and where customers operate very close to set point, as such they cycle frequently on high energy systems. Difficult service for the most robust pressure relief valve designs.
A joint team of engineers and technicians from Stafford and Wrentham approached this product line with new perspective. Stafford engineering brings to the table years of process design and pilot experience, the Wrentham team has the largest high temperature steam test facility in the world and 125 years of high temperature safety valve experience.
One component of the 727 design that takes a lot of abuse is the unloader piston. Unloaders are used on the 4 in., 6 in. and 8 in. valves in steam service. A series of side by side tests were performed to compare the original unloader design in 17- 4PH stainless steel with a new design made from Inconel 718. The results were compelling. Inconel 718 outlasted 17- 4PH stainless steel from 5 to 10 times.
Based on the test results listed above Anderson Greenwood Crosby has made a design change to the 727 product line. All new valves will be supplied with Inconel 718 unloader pistons and all unloader pistons supplied as spare parts will also be made from this new material.
Anderson Greenwood Crosby suggests that all 727 customer consider replacing their existing 17-4 PH unloader as part of their next routine maintenance.
<%=company%>, 3950 Greenbriar, Stafford, TX 77477. Tel: 281-274-4400 Ext. 4439. Fax: 281-274-4655.