ASME B16.34 minimum wall thickness 3 pieces trunnion ball valve.
ASME B16.34 minimum wall thickness 3 pieces trunnion ball valve.
(OP)
Dear all,
When designing a 3 piece trunnion ball valves the point 6.1.2 part c point 1. Says:
for the central core piece, the value of d shall be the inside diameter of the core piece. If the core piece wall has axial holes, whether through- or partial threaded, then the inner and outer ligaments shall also meet the requirements of dimensions f and g of Fig. 2.
This is very clear f and g have to be minimum 25% of the minimum wall thickness t.
But the questions is.
Does it apply in this type of valve the point 6.7 ( wafer and flangeless valves) part e that says that the sum of inner and outer ligaments f+g shall not be less than t?
Thanks
When designing a 3 piece trunnion ball valves the point 6.1.2 part c point 1. Says:
for the central core piece, the value of d shall be the inside diameter of the core piece. If the core piece wall has axial holes, whether through- or partial threaded, then the inner and outer ligaments shall also meet the requirements of dimensions f and g of Fig. 2.
This is very clear f and g have to be minimum 25% of the minimum wall thickness t.
But the questions is.
Does it apply in this type of valve the point 6.7 ( wafer and flangeless valves) part e that says that the sum of inner and outer ligaments f+g shall not be less than t?
Thanks





RE: ASME B16.34 minimum wall thickness 3 pieces trunnion ball valve.
RE: ASME B16.34 minimum wall thickness 3 pieces trunnion ball valve.
What I don't see clear is if the sum of the 2 ligaments really apply because point 6.7 refers to wafer or flangeless valves. And a center piece of a 3 pieces ball valves is not a waffer design.
Any other opinion?
Thanks
RE: ASME B16.34 minimum wall thickness 3 pieces trunnion ball valve.
The committee added the extra wall thickness and ligament requirements for the center section of 3 piece ball valves about 2 revisions ago. Since then, there have been a lot of complaints about the extra weight it caused. Especially when there was not a problem in the first place. So the next revision will allow the wall thickness to be determined by the end port connection diameter, not the center body bore.
RE: ASME B16.34 minimum wall thickness 3 pieces trunnion ball valve.
Its good to know that this will change during this year, but do you know if with the actual revision, the sum of the ligaments f+g>t apply to the 6.1.2 (c) point 1?
Thanks
RE: ASME B16.34 minimum wall thickness 3 pieces trunnion ball valve.