Spellman LORAD LPX-200, Руководство оператора

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LPX-200
Industrial Imaging System
6-5 Chapter 6: LPX-200 Routine Upkeep and Care
Re-Pressurizing the Tubehead
This x-ray unit operates safely at Tubehead gas pressures as
low as 50 psi @ 70
° F. Should Tubehead gas pressure fall
below this value, but remain above 5 psi (as indicated on the
pressure gauge), Re-pressurizing is required.
This procedure details how to re-pressurize the Tubehead with
dry sulfur hexafluoride gas to bring the Tubehead gas pressure
to within acceptable levels (50 - 55 psi @ 70
° F). This is done
through the charging valve (automobile tire type) on the back
plate of the Tubehead assembly. Use a hose incorporated with
a relief valve or pressure regulator, and a gauge having an
accuracy of at least 4 psi. Note that a charger and
maintenance kit for the Tubehead is available, and can be
purchased through LORAD (see
“ Optional Equipment
Checklist ” in Section 2 of this manual).
Refer to Figure 6-1 and 6-2 while performing this procedure.
! CAUTION !
If gas pressure is below 5 psi @ 70°F,
contaminants which could cause arcing
may have entered the Tubehead chamber. If
Tubehead gas pressure is below 5 psi (at
70°F), the Tubehead must be purged and
then re-filled (see Re-Filling the Tubehead).
DO NOT perform the Re-pressurizing
procedure.
1. Remove the protective cover from the SF6 (sulfur
hexafluoride) cylinder (2). Remove the plug from
the cylinder valve (3) with a 3/8" allen wrench. The
cylinder valve outlet is left-hand threaded.
! WARNING !
Use extreme care while handling the
cylinder to preventing dropping it
after the protective cover has been
removed. Secure the cylinder to a
stationary post, or secure it against
tipping.
2. Connect the SF6 charging regulator assembly (6), or
equivalent, to the SF6 cylinder valve.
NOTE:
The pressure regulator supplied with the optional
LORAD recharge kit is factory set to 70 - 75 psi @
70°F, and locked with a hex nut on the adjustment
knob. However, due to spring tension aging, and/or
various ambient temperatures, this setting may need
to be updated.
3. Connect the Tubehead (1) to the regulator assembly
(6) using the hose (8), as shown in Figure 6-1. Leave
the SF6 cylinder closed at this time. For this
procedure, hose (9), and pump (10) are not required.
4. Open the vacuum line valve (7) slightly, to purge the
hose (8) of standing air. Open the SF6 gas cylinder
slightly to purge the regulator of any standing air.
Now close the vacuum line valve (7), and open the
SF6 cylinder valve (3) to its fully open position
(against its physical stop).
5. The Tubehead will begin filling with SF6. When the
gas gauge indicates the correct pressure, close the
SF6 cylinder valve (3). To determine the correct
pressure, refer to the
“ Pressure vs. Temperature ”
chart (Figure 6-2).
6. Remove the charging hose connection at the
Tubehead. Secure the gas cylinder by removing the
connections and replacing the protective cover.
Recheck the pressure and inspect the Tubehead for
leakage.