BALL MATERIAL FOR VALVES
BALL MATERIAL FOR VALVES
(OP)
Hi All
As per datasheet for pipeline ball valve(API 6D) ,the ball material is UNS S32750(SDSS). Only material grade is mentioned in datasheet. One Vendor is offering bar material(A276) for the ball but other vendor is offering forged material (A182 F53).As my understanding bar stock has a higher risk of porosity and flaws over forged material. Plz give more details for bar material Vs forged type.
Vendor is proposing 3 piece design instead of 2 piece design for ball valve. Plz clarify which one is better in design as well as price.





RE: BALL MATERIAL FOR VALVES
RE: BALL MATERIAL FOR VALVES
"Even,if you are a minority of one, truth is the truth."
Mahatma Gandhi.
RE: BALL MATERIAL FOR VALVES
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P.E. Metallurgy, Plymouth Tube
RE: BALL MATERIAL FOR VALVES
Absolutely do not agree.
RE: BALL MATERIAL FOR VALVES
You have to know the details of the specs.
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P.E. Metallurgy, Plymouth Tube
RE: BALL MATERIAL FOR VALVES
RE: BALL MATERIAL FOR VALVES
This is both good and bad.
In many cases there is no practical issue, as the extruded part will have the same structure and properties as an open die forging. But in cases of alloys that develop strong preferred orientations it can be an concern.
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P.E. Metallurgy, Plymouth Tube
RE: BALL MATERIAL FOR VALVES
Steve Jones
Corrosion Management Consultant
http://www.linkedin.com/pub/8/83b/b04
All answers are personal opinions only and are in no way connected with any employer.
RE: BALL MATERIAL FOR VALVES
Ball Valve is 16" full bore valve design for 150#
RE: BALL MATERIAL FOR VALVES
RE: BALL MATERIAL FOR VALVES
RE: BALL MATERIAL FOR VALVES
RE: BALL MATERIAL FOR VALVES
The better question is what NDT are they doing on the ball? That is the issue with any product form.
Also ask about the heat treatment, all superduplex should be tested to ASTM A923 B or C to assure proper anneal.
A part this size would require annealing after it is bored.
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P.E. Metallurgy, Plymouth Tube
RE: BALL MATERIAL FOR VALVES
I have cast several balls of this size, and they are well received.
"Even,if you are a minority of one, truth is the truth."
Mahatma Gandhi.
RE: BALL MATERIAL FOR VALVES
My main concern would still be metallurgical condition, not manufacturing process.
These alloys are very easy to HT wrong, and the resulting corrosion resistance is very poor.
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P.E. Metallurgy, Plymouth Tube