Category: Industrial

Catalina Cylinders recommends the following procedure for the valving of industrial gas cylinders.

    1. Inspect the inlet and outlet threads of the valve and the threads and o-ring
      gland of the cylinder for damage to the threads and o-ring area. If either
      the valve or cylinder has damage to the threads or the o-ring area, do not
      insert the valve into the cylinder.
    2. Inspect the cylinder threads and the cylinder internally verifying that
      the cylinder is free from any lubricants and contaminants. Do not proceed
      if you feel the cylinder may be contaminated.
    3. Catalina Cylinders recommends the insertion of a new buna-N o-ring when
      the old o-ring shows any sign of tearing or wear.

Cylinder Thread Designation

Valve Designation

O-ring Size

1.125 – 12 UNF

CGA 580



    1. Catalina Cylinders has found it easiest to place the o-ring on the valve
      and then insert the valve into the cylinder tightening the valve hand tight.
    2. Final tightening of the valve should be done with a calibrated torque wrench
      to the recommended torque value noted below:

1.125 – 12 UNF

40 lbf – ft

50 lbf – ft
– 16 UNF

40 lbf – ft

50 lbf – ft


  1. Close the valve with no more than 1 lbf – ft torque.
  2. Do not tamper with the safety device of the valve. The safety device of
    the valve should be rated at the test pressure of the cylinder.
  3. Whenever replacing the safety device of a valve, Catalina Cylinders recommends
    that you always replace the safety device with a complete new safety device
  4. Always verify that the cylinder is empty prior to attempting to replace
    the safety device of a valve.