Diaphragm Valves Body Design And Finish

Saunders® Body Range
Saunders® offers bodies with weld and clamp ends to meet all global tube and pipe specifications. This includes: OD tube, DIN, ISO, SMS and schedule pipe.
Standard body material for all forged bodies is stainless steel dual certified to 316L (ASTM A-182) and DIN 1.4435 with the additional requirement of controlled sulfur per ASME BPE Standard.
Cast bodies are available from 316L stainless steel. Bodies produced from alternate materials such as Hastelloy®, AL6XN, 904L and Titanium are also available.

Drainability
The diaphragm valve has outstanding self-draining characteristics and is capable of draining in both vertical and horizontal orientations.

Factors which affect drainability include:
• Valve size and tube specification
• Internal surface finish
• Drain orientation
• Surface tension and viscosity of media
• Pipe run angle – generally recommended at 2–3 degrees
Drainability in a process system is ultimately the responsibility of the system designer and end user as a result of the factors explained above.

Surface Finish
Saunders® valve bodies are available in all mechanically polished and electropolished surface finish options to match piping system specification. Saunders® valve bodies are also available in a complete range of ASME BPE compliant internal surface finishes.

Electropolishing
Electropolishing of mechanically polished product contact surfaces improves surface finish smoothness and corrosion resistance. Mechanical polishing or machining may leave numerous microscopic surface imperfections which can cause areas of differing electrical potential due to surface stresses.