Buchi DuMaster D-480, Operation Manual, Page: 203 / 354

Operating instructions DuMaster D-480 ©BÜCHI Labortechnik AG
8 - Maintaining the instrument 203
Dismantled ball valve
The following picture shows the disassembled ball valve:
Legend:
1 Wheel flange of the half shells
2 Top and bottom half shell
3 Ball
4 Screws
5 Drive bearing
6 Holder plate
7 O-ring
8 Bayonet catch
Phase 1: Cleaning the half shells and ball
Proceed as follows:

Clean the half shells (2) and the ball (3) with acetone.

Check the half shells (2) for grooves. If there are any grooves, replace the half shells.

Check the ball (3) for grooves. If there are any grooves, replace the ball.
Phase 2: Assembling the ball valve
Proceed as follows:

Slighly grease the sealing surface of the half shells and the surface of the ball (contact surface of
the ball).

Insert the bottom half shell (2) and observe the recess for the drive bearing. Insert the ball (3)
and observe the position of the recess for the drive bearing.

Insert the drive bearing (6). Observe the following

the fit of the o-ring (9)