Tube Conditioning / Seasoning; Tube Conditioning (Overview); Tube Conditioning (Procedure) - CPI Indico 100 Series Service And Installation Manual

CPI Canada Inc
6.8.0

TUBE CONDITIONING / SEASONING

Tube conditioning or "seasoning" is particularly important for new tubes or tubes that have not been used for
several days. This should be performed on each X-ray tube before attempting auto calibration, as an
unseasoned tube may not operate properly at higher kV values without arcing. Refer to the X-ray tube
manufacturer's instructions, if available, for the tube conditioning or "seasoning" procedure. If the X-ray tube
manufacturers instructions are not available, the following procedure may be used:
6.8.1

Tube Conditioning (Overview)

The generator does X-ray tube auto calibration at 50 kV, 60 kV, 70 kV, 80 kV, 100 kV and 120 kV. The tube
normally needs to be seasoned before it can be operated at the higher voltages encountered during auto
calibration.
Tube seasoning is started by auto calibrating the kV stations up to and including part of the 70 kV
station. The tube is then seasoned at 70 kV. Progressively higher kV stations are then auto calibrated and
seasoned. Finally the entire kV and mA range is auto calibrated, then the tube is seasoned at the remaining
high kV values.
Manually releasing the exposure button during auto calibration of a particular kV station in the following
procedure prevents the generator from attempting operation beyond that kV/mA value.
NOTE: THE TUBE MANUFACTURER'S RECOMMENDED SEASONING PROCEDURE, IF AVAILABLE,
MUST ALWAYS BE USED IN PLACE OF THE FOLLOWING PROCEDURE.
NOTE: LOW SPEED ONLY EXPOSURES ARE RECOMMENDED FOR THE SEASONING EXPOSURES, TO
PREVENT EXCESSIVE HEAT BUILD-UP IN THE HOUSING FROM THE STATOR WINDINGS OR
THE ROTOR BEARINGS.
X-ray tubes that have not been used for more than 8 hours may suffer thermal shock if operated at high
mA and kV without a warm-up procedure. A cold anode (Molybdenum) is very brittle and when
suddenly heated over a small area may experience thermal cracking of the anode surface, eventually
leading to permanent tube damage.
6.8.2

Tube Conditioning (Procedure)

The procedure below is intended for seasoning an X-ray tube prior to attempting tube auto calibration. To
season a tube that does not need to be calibrated, simply follow steps 2, 4, 6, 8, and 9.
1. Start the tube auto calibration sequence, and manually terminate the exposure at 70 kV and 250 mA.
2. Season the tube at 70 kV by taking approximately 10 exposures of 200 mA and 100 ms. These
exposures should be taken at the rate of approximately one every 15 seconds.
3. Restart the auto calibration sequence and manually terminate the exposure at 100 kV and 250 mA.
4. Season the tube at 100 kV by taking approximately 5 exposures of 200 mA and 100 ms. These
exposures should be taken at the rate of approximately one every 15 seconds.
5. Restart the auto calibration sequence and manually terminate the exposure at 120 kV and 160 mA.
Millenia / Indico 100 Series Service Manual Ch # 740904-10 Rev. D
6
Regular Maintenance
Page 6-9