Using a Body Purge Assembly

Prior to use, it is recommended that you familiarise yourself with the key components of the body purge:

(A) Cylinder connection
(B) Purge gas inlet valve
(C) Pressure regulator
(D) Outlet valve

When to purge

The procedure outlined below should be used:

- before changing the process gas cylinder
- after changing the process gas cylinder
- before the equipment is to remain unused for some time
- after the equipment has remained unused for some time
- if you have any reason to suspect that the equipment has been contaminated


Purge procedure

  1. Connect the assembly to the process gas cylinder and tighten the connection (A)
  2. Connect the purge gas supply to the inlet compression fitting on the purge gas inlet valve (B). The purge gas should be good quality, dry, oxygen free nitrogen or similar inert gas at a pressure of 5 barg (NB - Purge gas pressure should not exceed 6.9 barg)
  3. Wind the regulator (C) hand wheel fully clockwise to open
  4. Ensure that the outlet valve (D) is closed  (NB -If the pipework is connected to the outlet of the regulator, there must be a vent available to permit the effluent gas to be flushed from the system)
  5. Open the purge gas inlet valve (B) to permit the equipment to be flushed through with purge gas. This process should continue for at least 2 minutes.
  6. At the end of the purge close the purge inlet valve (B), turn the regulator hand wheel (C) fully anti-clockwise to close it and close the outlet valve (D)
  7. Open the cylinder valve and pressure will register on the inlet gauge of the regulator (C). Set the desired outlet pressure by turning the regulator hand wheel clockwise. Open the outlet valve (D) to supply gas to the process.

Call us on

  • Phone 0800 020 800

Store Finder

To locate your nearest BOC retail outlet please enter town or postcode