Fluke Calibration P3031, Руководство пользователя

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5-1
Chapter 5
Maintenance & Servicing
Introduction
W
Caution
The piston / cylinder assembly is the most critical and sensitive
part of the deadweight tester. To maintain accuracy, the piston
must always slide freely in the cylinder, and the gas supply
must remain clean and dry.
The Figures on the following pages detail the components of each assembly, together
with the relevant part numbers. Where “SPEC” appears as a part number, this indicates
that this particular component varies with the specification of the deadweight tester, and
is usually associated with other components in an assembly for replacement purposes.
A replacement seal kit is available for instruments covered by this manual,
part number 3874964.
PCU Assembly
Piston Disassembly
1. Hold the weight carrier (1), and lift the piston to its full extent. Unscrew cylinder
retainer (5), and lift out PCU assembly.
2. Unscrew set screw (2) two turns, and remove weight carrier (1).
3. Remove cylinder retainer, and carefully withdraw the piston from the cylinder.
Piston Cleaning
4. Use “non-fluffing”, non-abrasive, lint-free tissue or absorbent cloth. Hold the piston
by the larger “head” end, and rub the tissue back and forth along its length.
5. To remove all traces of contamination, the piston can be cleaned in a suitable solvent.
6. After removal from the solvent, using a NEW tissue, repeat the cleaning procedure in
step 4.
7. Place piston carefully on a NEW tissue where it will not be damaged while the
cylinder is cleaned.
W
Caution
Never touch the working surface of a clean piston with bare
fingers — the natural oil in your skin can cause the piston and
cylinder to stick.
8. Wipe any dirt or moisture from the outside surfaces of the cylinder (3).