Howden WRV, Руководство по обслуживанию, Страница: 13 / 64

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3.3 DOWELLING
Only one unit of any assembly will be dowelled before despatch. Dowels should be fitted to ease re-
alignment when components are removed for overhaul.
3.4 PIPING
Before installing the piping the compressor inlet and outlet ports should be inspected to ensure no
dirt is present.
Note that the pipes and fitting used should not restrict flows. To avoid this always use piping with a
bore ¼” larger than the thread diameter of the compressor port, eg, WRV 204 oil injection
connection thread is ¾” BSP and so a 1” OD pipe should be used.
NOTE: All piping should be supported so that no strain is transmitted to the compressor casings.
The piping should be inspected for cleanliness before installation. As each pipe is connected to the
compressor, the coupling alignment should be checked to ensure that no alteration has taken place.
If alignment has altered the compressor is being strained and the piping supports must be adjusted.
It is not sufficient merely to re-align the drive unit as this will not correct the strain being imposed on
the compressor. Oil injected refrigeration compressors must have a suction strainer permanently
fitted directly on the compressor inlet.