Rotair D425T4F, Operating Maintenance Instructions & Part List

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USER'S AND
MAINTENANCE
MANUAL
Date: 22/12/2016
Code MAN D425T4F ENG
Motor compressor D425T4F
Revision 00
Copyright © 2014, ROTAIR S.P.A. - All rights reserved This manual is intellectual property of ROTAIR S.P.A. Its
full or partial reproduction is forbidden under any form, on any support and by any means, without the written
authorization by ROTAIR S.P.A.
Page
23/57
7 MACHINERY COMPONENTS
This unit is a single-phase, silenced oil injection screw mobile motor compressor.
The engine is internal-combustion, fuelled by gas oil, and is connected to the compressor by flexible coupling.
7.1 Chassis
The chassis is made from contoured and electrowelded metal sheet and is of load-bearing type. This chassis
undergoes two painting treatments which guarantee corrosion resistance and rust-proofing.
In the chassis there is the control panel which is protected by a transparent polycarbonate lid and which allows
the compressed air pressure, the ON/OFF button and the electronic control panel that allows to control all the
warnings which will indicate any anomalies of the machine element to which it is connected.
7.2 Body
The body is built entirely out of galvanized sheet iron. It can easily be turned over thanks to a gas hoist and
thus allows convenient access to the main machine elements. The whole machine is entirely lined with sound
absorbent and fire-retardant material.
Special holes have been created in the elements forming the body, complete with baffles, which allow the cool
air necessary for engine and compressor cooling to be sucked in from one side and the heated air to be expelled
from the other side. These baffles have been carefully designed in terms of size and shape so as to allow the
most efficient internal ventilation of the machine: it is advisable, therefore, to make sure that these openings
are kept free and undamaged.
All the parts of the body have been treated with a special painting process which guarantees excellent finishing
quality together with maximum impact and rust resistance.
7.3 Engine
The unit is equipped with a Diesel engine whose features are described in Section 2.
As related to the user's and maintenance instructions, refer to the manual provided by the Manufacturer and
enclosed to the documentation relevant to this machinery.
7.4 Compression unit
It is completely manufactured in the ROTAIR factory and consists of a central body (cylinder) inside which are
fitted two screw rotors with asymmetric section, a male one with 5 lobes and female one with 6 lobes.
The cylinder is closed at the ends by two head sections which contain the bearings which bear the radial and
axial loads created by the air compression. A series of channels, inside the cylinder and heads, undertake to
deliver the oil to the various components. The distribution of the lubricant, serves to lubricate the bearings and
to maintain a coating of oil between the rotors and the bearings themselves as well as the internal cylinder
walls, thereby promoting compression resistance. Another important function of the oil injected between the
rotors is that of absorbing the heat generated by the air compression.
The compressed air supplied by this compressor is free of any pulsations and compression comes about axially.
A "regulator" unit is mounted on the compression unit, the purpose of which is to regulate the quantity of air
taken in according to the amount of air consumed. A double-stage filter mounted on the top of this unit
guarantees maximum purity of the suctioned air.