How to clean the internal components of a Penning gauge - WKB17711

OBJECTIVE or GOAL

Clean the internal components of a Penning vacuum gauge.

ENVIRONMENT

• Xevo TQ-S
• Xevo TQ-XS

PROCEDURE

1. Rotate the collar clockwise to unscrew it from the body tube.
2. Remove the anode assembly and the O-ring.
3. With lock-ring pliers, remove the circle clip from the body tube.
4. Remove the cathode tube and the cathode plate.
5. The anode assembly has a bracket mounted close to the disk on the anode; use a strip of fine emery paper to clean the gap. Ensure that the gap is 0.25 mm, minimum.
6. Use emery paper or a fiberglass pen to clean the cathode tube, the cathode plate, and the body tube.
7. Further clean the cathode tube, the cathode plate, and the body tube as follows: Sonicate in 1:1 methanol/water for 30 minutes; rinse with 100% water and then with 100% methanol; blow dry with nitrogen.
8. Fit the cathode plate and tube in the body tube and secure with the circle clip.
9. Fit a new O-ring and the anode assembly into the body tube, ensuring that the orientation is correct.

ADDITIONAL INFORMATION

It is not really reccommended to clean the internal parts of a Penning gauge as the interval between cleanings will decrease dramatically.
You are much better advised to replace the item completely.  Waters Part Number: 6061138

Note:  The Body tube is identical for all Edwards Penning gauges utilised on Quad and TOF systems.