tank valves

[Ontwreckdiver]

I just bought a pair of O.M.S. 112 steel tanks with modular/K valves. My question is the tanks have a working pressure of 2650psi but the tank valve burst disk service pressure is only 2400psi and a rupture pressure of 3600 to4000psi. Is going to cause a problem? The non modular valve burst disk service pressure is 3000psi and the rupture pressure is 4500 to 5000psi. When I ask him about this he said he hadn't noticed this before . He said they usually fill the lp steels to 3000psi and haven't changed the burst disks. Should I ask him to change the disks before I pick up the tanks. Thank you in advance.

 

[DA Aquamaster]

The DOT requires a burst disc that will fail at no more than or 10% below the hydrostatic test pressure.

My understanding is that the OMS 112 has a service pressure of 2400 psi, and that 2640 psi is with a 10% overfill. So the 2400 psi valve is correct for the tank as the burst disc would be expected to fail at 3600 to 4000 psi. given that the hydro test pressure is 4000 psi.