A533-23-880 Issue C
Page 90
© Edwards Limited 2009. All rights reserved.
Edwards and the Edwards logo are trademarks of Edwards Limited.
maintenance
'O’ ring replacement intervals vary depending on your application - your local Edwards office can provide
assistance.
Do not reuse 'O' rings.
Dispose of components, grease and oil safely (refer to Section 7.2).
Take care to protect sealing-faces from damage.
Do not touch or inhale the thermal breakdown products of fluorinated materials which may be present if the
iF system has been overheated to 260
o
C and above. These breakdown products are very dangerous.
Fluorinated materials in the iF system may include oils, greases and seals. The iF system may have
overheated if it was misused, if it malfunctioned or if it was in a fire. Edwards Material Safety Data Sheets
for fluorinated materials used in the pump are available on request: contact your supplier or Edwards. (refer
to Section 1.1 for contact numbers).
Leak-test the system after maintenance work is complete if you have connected or disconnected any vacuum
or exhaust joints; seal any leaks found.
Wipe up any water or oil spilt during maintenance to avoid possible risk of slips.
Route and secure cables, hoses and pipe-work during maintenance to avoid possible risk of trips.
6.2
Correct use of tube fittings
Note:
We recommend that you use a second spanner to hold the connector in position when you connect or
disconnect a tube fitting.
You must know how to correctly fit and tighten tube fittings in order to prevent gas leaks; use the procedures in the
following sections.
6.2.1
Fit a tube fitting
1. Refer to Figure 46 detail A. Undo and remove the nut (4) from the tube fitting (1). Ensure that the front
(tapered) ferrule (2) and the rear ferrule (3) are correctly orientated as shown in detail A, then loosely refit the
nut (4) to the tube fitting (1).
2. Refer to detail B. Insert the tube (5) through the nut (4) and into the tube fitting (1). Ensure that the tube rests
firmly on the shoulder inside the fitting, and that the nut (4) is finger tight.
3. Tighten the nut (4) until you cannot rotate the tube (5). If you cannot turn the tube because of how it is
installed, tighten the nut by 1/8 of a turn.
4. Refer to detail C. Mark the nut (4) at the six o'clock position.
5. Refer to detail D. Hold the body of the connector steady, then turn the nut (4) by 1 and 1/4 turns (to the nine
o'clock position) to fully tighten the connection.
6.2.2
Reconnect a tube fitting
You can disconnect and reconnect a tube fitting many times and still obtain a correct leak-proof seal. Refer to Figure
46 detail A which shows a tube fitting after you have disconnected it. Use the following procedure to reconnect it:
1. Refer to detail B. Insert the tube (5) with the swaged ferrules (2, 3) into the tube fitting (1), until the front
ferrule (2) is fully in the body of the fitting.
2. Refer to detail C. Tighten the nut (4) by hand.
3. Use a wrench or spanner to turn the nut (4) to its original position (you will feel an increase in resistance when
the nut is in its original position), then tighten the nut slightly.
