Hi Hasham. You can directly post your pictures into the forum using the icon.
That prevents everyone who visits from having to click 2 to 4 times per picture.

You can now delete your last 4 posts and EDIT your first one to remove the link. It will be appreciated.

Keith Cress
kcress - http://www.flaminsystems.com

I think you need to do a thickness check all over the casting. It may be just the visual aspect of the photo but the one at the top of itsmokeds post above makes it look thinner at the bit closer to the persons arm than other bits of the casting.

Also is that discolouration surface dirt or evidence of a fatigue crack.

Some technical data would be useful

Material
Pressure rating
temperature
Fluid
what happened
Any external bending forces present?
what does the piping around it look like?
Flow direction - Up vertically up or down?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

Apart from the wall thickness being not uniform, why is the fracture white?

"Even,if you are a minority of one, truth is the truth."

Mahatma Gandhi.

My theory:

- looks like a 2" globe valve
- looks like some fairly generalized corrosion on both seat and valve plug
- handle is broken
- valve was probably leaking through, and operator decided to crank it down to get shutoff, using mechanical advantage (extreme torque). High torque generated high compression on stem and correspondng high tensile on valve case resulting in fracture.

Good spot about the handle (first photo). Would allow a bit of hammering to take place as well maybe...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

Hypothesis:

Corroded valve seat. Valve wouldn't seal properly. Operator applied an oversized wheeldog and broke the handwheel on the first attempt. They then had a second go further round the wheel and the body casting fractured in tension due to excessive seating force on the stem.

Pretty much as Brian said above. Happens from time to time.

I agree with the above posts, although freezing water is another possibility.