Cast Valves with BW ends 1

[Valving]

Do regular cast valves have problems with BW ends? I heard a vendor applying steel rings to cast body in order to prevent shrinkholes. Would you pls. share your ideas? Thanks !

 

[hsbcn]

If you're referring to problems related to thermal expansion, the following thread might be of interest:

http://www.eng-tips.com/viewthread.cfm?qid=312505

My focus is on valve stockists in the us and uk who supply duplex and super duplex valves, and inconel and hastelloy valves, plus titanium, alloy 20 and 904L valves.

 

[Valving]

No actually what I am concerned is, a cast valve having buttweld ends has any kind of smooth buttweld surface issues? After casting, is there any problem with buttweld ends? Is there a special way to solve this issue ?

 

[PAN]

What is your cast valve material?

 

[gerhardl]

Any quality BW valves from reputed factories will have written instructions for installment, eg. a description on how to weld the valves to pipelines. This would imply methodes, welding type, material etc. etc. This procedure could also set down requirements to material properties and dimensions and form of the pipeends.

If all this is checked and OK, you should be safe.

 

[valvit]

Most end users will specify to have the butt weld end subjected to a form of volumetric NDE such as radiography or ultrasonic testing for a minimum dimension of 50 mm from the end. Reputable manufacturers will do so whether the customer specifies it or not. The idea being to locate any defects in the BWE area and perform a weld repair before the valve is welded into the pipeline. As with all cast products, there will be defects in the casting. If you have defects in the weld bevel area, it will be very difficult (if not impossible) to weld the valve in the pipeline.

 

[nmiller127]

There are some check valves that have their bodies made from bar stock instead of a casting. Check All valve is one of them I came across on a Google search.