Philips PW 1720 User Manual

Page 6

Typical window applications are shown below:

Line focus

Powder diffractometer

Guinier camera

Point focus

Debye - Scherrer camera

Texture goniometer

Laue camera

Weissenberg camera

Precession camera

Reciprocal lattice explorer

3.6.

CHANGING THE X-RAY TUBE

To change the X-ray tube, proceed as follows:

1 . Switch off by pressing the GENERATOR 0 push-button.

2. Turn off the water supply.

Drain water from the instrument by opening the air inlet valve next to the water inlet and outlet

connections, and wait until air has filled the system. Some water may run from the air inlet valve.

Loosen the two captive screws at opposite corners on the top of the tube shield. The X-ray tube should be

removed by lifting upwards, when handling the X-ray tube take care to hold by the metal base and

DO NOT TOUCH THE BERYLLIUM WINDOWS. These windows are thin, and can be poisonous to the skin.
Do not remove the X-ray tube if generator operation has been switched off because of a failure
(safety circuit actuated) see Service section.

Select the new tube and insert into the tube shield, after first checking the condition of the “0” rings

for the water tubes. There is a locating pin on the top of the tube shield to ensure correct positioning of

the tube. Tighten the two fixing screws.

NOTE:

The tube shield is designed to accept X-ray tubes with dimensions as figure 3.3. version A.

For other tubes a spacer ring, such as PW 1043, will be necessary when the dimension from the
underside of the tube base to the centre of the tube base to the centre of the tube window exceeds 21 mm.

Note that dimension "a" must not exceed 120 mm.

Fig. 3.3. X-ray tube dimensions.