Spellman SPX Series, Manual

Page: 6 / 51

SPX X-ray
Industrial Imaging System
Page 4 of 44 SPX Series System Manual
118173-001 Rev. D
The Control Unit
The radiographer uses the Control Unit to set the
radiographic exposure parameters, and to
activate/deactivate x-ray emissions from the Tube
Head. One hundred feet of cable is supplied with the
system, which enables the Control Unit and operator to
maintain a safe distance from the X-ray Tube Head
during use.
The digital-based, micro-processor-regulated Control
Unit houses all the system pushbutton operating
controls, and exposure factor Vacuum Fluorescent
Display (for display of exposure factors, a Message
Vacuum Fluorescent Screen (for display of operating
mode and system messages), and the circuitry required
to provide power to the Tube Head and Cooling Unit.
The Control Unit is enclosed in a metal chassis and a
handle is provided as a means of transporting it.
The Tube Head
The Tube Head is a cylindrical aluminum shell
assembly housing the x-ray tube, the high voltage
power supply and the filament supply. It is insulated
with sulfur hexafluoride gas that is pressurized to 50 psi
@ 70
˚ F. Power to operate the x-ray tube is supplied
through a shielded cable that connects the Tube Head
to the Control Unit. The x-ray tube is end-grounded,
with an exposed anode that contains a beryllium
window approximately 2 inches from the anode end.
Built-in carrying handles are at each end of the Tube
Head.
There are two Tube Head models available:

Liquid-cooled

Air-cooled
The liquid cooled Tube Head uses a separate Cooling
Unit to dissipate anode heat. These models have a
length of twin hoses attaching the Tube Head to the
Cooling Unit. Air-cooled models have an electric cooling
fan mounted at the end of Tube head. The fan is
powered by an inter-connecting cable from the Control
Unit.
The Cooling Unit
(liquid cooled units only)
The Cooling Unit dissipates heat generated at the
anode of the x-ray tube. Liquid coolant from a self-
contained reservoir is pumped through one side of a
twin hose assembly into the Tube Head. Coolant flows
through a manifold in the Tube Head into the anode
and returned to the Cooling Unit through the second
half of the twin assembly.
Once in the Cooling Unit, coolant passes through a flow
switch that is electrically interlocked with the Control
Unit, and then through a filter to screen out
contaminants. The coolant exits the filter and flows
through a forced air radiator where the conducted heat
is dissipated and then back into the reservoir.
An electric motor-driven fan and pump assembly
circulates coolant and creates airflow through the
radiator. Power is supplied via an interconnecting cable
from the Control Unit. When properly connected to the
system, the Cooling Unit is automatically activated by a
switch circuit within the Control Unit.