5
EN
Pressure Regulator
LAB11141_Issue 1
June 2019
5 INSTALLATION
5.1
Position the gas cylinder/vessel in the desired location, ensuring it is secured correctly. Note, all gas cylinders should be vertically positioned or installed in
line with the manufacturers/suppliers instructions.
5.2
Before installing your pressure regulator ensure that it and the connection to the cylinder/system show no signs of damage or contamination, in particular
the presence of oil or grease. Ensure your pressure regulator is in its fully closed position (pressure adjusting knob fully unwound anti-clockwise).
5.3
Install the regulator by connecting the inlet connection to the cylinder/vessel/system in the appropriate manner using the correct torque settings as laid
out in the applicable cylinder connection ‘Regional Standard’. Note, the direction of thread could be either left or right handed, normally indicated by a
‘Notching’ applied to left hand threaded connections.
5.4
If connecting a pipeline regulator to a piped system, install the regulator by applying the correct PTFE (Teflon) tape to the male connecting ¼ NPT thread.
Please note that on stainless steel connections the thread tape helps prevent the connections from galling together when tightening or loosening.
5.5
Start the PTFE tape on the second thread as shown below in
figure 1
; making sure the tape does not overlap the end of the fitting. As the tape is wrapped
in the direction of the thread spiral, pull tightly on the end of the tape so the tape conforms to the threads. Wrap the tape around the threads twice, cut off
the excess tape and press the end firmly into the threads as shown in
figure 1.
5.6
Once the PTFE tape is applied and the mating female connection is ready for installation, screw the connections together (clockwise) until tight. Please note
that ¼ NPT joint torque setting = 20 Nm (15 lbf-ft), however slight adjustment may be needed to ensure the regulator is in an up-right position
6 OPERATION
6.1
After connecting your equipment to the inlet feed and before opening the cylinder/isolation valve, connect the appropriate downstream equipment, if
applicable using the PTFE tape jointing guidance in
section 5.4 and 5.5
.
6.2
Ensuring that the pressure regulator is in the fully closed position (pressure adjusting knob fully unwound anti-clockwise), open the cylinder/isolation valve
slowly allowing the gas to enter the high pressure chamber of the regulator, which will indicate on the cylinder content gauge if fitted.
6.3
To pressurise your system or downstream equipment, gradually increase the outlet pressure by turning the pressure adjusting knob clockwise, increasing
the outlet pressure of the regulator in small stages of around 1 – 2 bar, ensuring the integrity of the regulator valve seat is not compromised.
6.4
When set at the desired pressure and the system is in a dynamic state (flowing), adjustments may be required to the operating pressure of the regulator to
allow for pressure decay over large systems or peaks in flow demand.
7 DECOMMISION
7.1
Firstly ensure there is adequate ventilation or the appropriate waste/vent facility.
7.2
Slowly close the cylinder/isolation valve feeding the regulator allowing the gas to purge through the regulator and out via the downstream equipment or
system. Note, all fitted pressure gauges must read
‘Zero’
pressure before the regulator can be removed.
7.3
If the gas is a corrosive, toxic or a pyrophoric gas, an inert purge gas may be required, fed in through the high pressure side of the regulator as detailed in
the ‘Deep Purge Section’.
7.4
When the regulator is de-pressurised and/or purged free of any hazardous gases, fully close the regulator (turn Pressure adjusting knob anti-clockwise) and
remove from the cylinder/system.
7.5
When a pressure regulator is removed from a cylinder, vessel or system, it should be stored in a dry safe location protected from contamination.
7.6
Dispose in accordance with applicable International, Regional, Country, Federal State, County or City laws/regulations.
8 PURGING
Purging allows the user to maintain gas purity, reduce the risk of corrosion and dilute any moisture, impurities, toxic or pyrophoric gases trapped within equipment prior to
use or decommissioning. This is achieved by fitting the appropriate waste/vent facility, or by installing a purge gas system fitted to the high pressure feed of any regulator or
system. When installing equipment or a full system for the first time, a full system purge or vacuum is required to remove any moisture, impurities or contamination prior to
use. Note, a downstream vent point will be needed to totally purge a fully installed system.
8.1
Tee Purge: Installation
8.1.1 To install a ‘Tee Purge’ to a pressure regulator, it may be necessary to remove the regulators inlet connection. This is achieved by securing the regulator
firmly in an appropriate manner (Gas-Arc Universal Cradle:
Part No. TOL01938)
, and unscrewing (rotate anti-clockwise) the connection free from the body
of the regulator (1/4 NPT joint).
8.1.2 When the connection is removed, clean the ¼ NPT male and female parts, ensuring existing PTFE tape is removed and they are free from contamination
and/or damage.
8.1.3 Fit the inlet connection to the inlet of the ‘Tee Purge’ as shown below in
figure 2
, using the PTFE jointing guidance detailed in
section 5.4 and 5.5
(clockwise).
8.1.4 Again using the above PTFE jointing guidance given, fit the outlet of the ‘Tee Purge’ to the inlet of the regulator (clockwise).
8.2
Tee Purge: Operation
When installed, the ‘Tee Purge’ facility allows the user to isolate the regulator or system and purge any air, moisture or impurities out of the high pressure feed without
contaminating the regulator or process. The user must ensure that the waste/vent valve discharges via a piped or contained system into a well-ventilated area.
8.2.1 When fitting the regulator and ‘Tee Purge’ assembly to a cylinder/vessel/system use the instructions detailed in
section 5.0
8.2.2 After the equipment is installed, but before opening the cylinder/isolation valve, ensure that both the high pressure isolation valve and the waste/vent valve
are closed. Slowly open the cylinder/isolation valve allowing the high pressure gas to enter the ‘Tee Purge’ assembly.
8.2.3 To purge any contamination free from the equipment, open the waste/vent valve for around 3 – 5 seconds allowing the process gas to purge out any
impurities. When purged, close the waste/vent valve and open the process valve allowing pure gas to enter the process line.
Figure 1
