Hydrostatic test

[pegus]

Good day,

I have worked validating chambers in which they performed pneumatic test, in which a component is filled with air and pressurized. For this validation there are tools that calculate the required vent area in case a decompression occurs, I understand that this is due to the air is highly compressible and the energy stored during a pneumatic test is greater than a hydrostatic test.

But I wonder what happens when a hydrostatic test is being validated (component filled and pressurized with water). If I understand correctly as the water is nearly non-compressible there is not much energy stored, and as soon as a failure occurs on the tested component, the water quickly decompresses and we dont have any air expanding and hitting the chamber. Do to this I have the following doubts:
1.-Do we need to consider any vent area for hydrostatic test?
2.-Do we need to take in consideration any possible projectile derived from the hydrostatic test? we do this for pneumatic, but I wonder if we need to follow the same path for hydrostatic test.

I would appreciate if you can recommend any reference to research more about it.

Thanks in advance,

 

[mk3223]

1. No. Instead, need to consider the source of testing water and where to dispose it.
2. Compared to hundreds feet of safety distance needed for the pneumatic testing, it may need about tenth feet distance for the hydro testing if not in the line of fire.

 

[zeusfaber]

Between the energy stored in the compressed water (which, although much lower than in a compressed gas, still exists) and that stored elastically in the walls of the component under test, there is still potential for harm.

It wasn't all that long ago I saw a one tonne concrete block chucked around a test site during a burst of the water-filled cylinder it had been covering up.

A.

 

[chicopee]

What was the code used to fabricate the cylinder? The reason that I am asking is that the ASME/NB has procedures to conduct hydrostatic tests of pressure vessels which do not require relief venting. The organization that fabricated the cylinder may have procedures similar to the ASME/NB.