Spellman SPX Series, Руководство пользователя

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SPX X-ray
Industrial Imaging System
Page 38 of 44 SPX Series System Manual
118173-001 Rev. D
Re-Pressurizing the Tube Head
This x-ray unit can be safely operated at
Tube Head pressures as low as 50 psi @
70º F. Should the Tube Head pressure fall
below this value, but remain above 5 psi (as
indicated on the pressure gauge), the Tube
Head will need re-pressurizing.
The following procedures outline re-
pressurizing the Tube Head to 50 psi with
dry sulfur hexafluoride gas (SF6) at 70º F
through the charging valve (automobile tire
type) on the back of the Tube Head. Use a
hose incorporated with a relief valve or
pressure regulator, and a gauge having an
accuracy of at least ±4 psi. Refer to Figure
7 -1 and Figure 7-2 while performing these
procedures.
! CAUTION!
DO NOT re-pressurize if Tube
Head pressure has fallen below
5 psi @ 70º F. Such low
pressures may have caused
contaminants to enter the Tube
Head chamber, and can cause
damage from high voltage
arcing. If pressure is below 5
psi, the Tube Head must be
purged of all remaining gas,
then re-filled. If the Tube Head
gas pressure is below 5 psi @
70º F, the Tube Head service is
necessary.
1. Remove the protective cover from the
SF6 (sulfur hexafluoride) cylinder.
Remove the plug from the cylinder
valve with a 3/8" allen wrench. The
cylinder valve outlet is left-hand
threaded.
! WARNING!
Extreme care must be exercised
while handling the cylinder so as
not to drop it after the protective
cover has been removed. The
cylinder must be chained to a
stationary post or otherwise
secured against tipping.
2.
Connect the SF
6
charging regulator
assembly, or equivalent, to the SF
6
cylinder valve.
NOTE... The pressure regulator
supplied with the optional Spellman
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 ageing. And/or various
ambient temperatures, this setting may
need to be updated.
3.
Connect the Tube Head to the
regulator assembly using the
hose, as shown in Figure 7-1.
Leave the SF6 cylinder closed
at this time. For this procedure,
hose and pump are not required.
4.
Open the vacuum line valve slightly, to
purge the hose of standing air. Open
the SF6 gas cylinder slightly to purge
the regulator of any standing air. Now
close the vacuum line valve and open
the SF6 cylinder valve to its fully open
position (against its physical stop).
5. The Tube Head will begin filling with
SF6. When the Tube Head gauge
indicates the correct pressure, close the
SF6 cylinder valve. To determine the
correct pressure, refer to the "Pressure
vs. Temperature" chart (Figure 7-2).
6.
Remove the charging hose connection
at the Tube Head. Secure the gas
cylinder by removing the connections