PREFACE
This INSTRUCTION MANUAL describes instructions and precautions to be observed in handling and
maintenance of
UDS
SCREW TYPE DRY VACUUM PUMP. It is strongly recommended that those who wish to
operate or maintenance
UDS
DRY VACUUM PUMP to read this manual carefully before operation for proper
operation, maintenance and long pump life.
1. GENERAL CONSTRUCTION
1.1 General
This Dry Vacuum pump discharge the inhaled gas under pressure by use of two screw rotors, having a profile
comprising plurality of curves, i.e. Archimedean curve, Quimby curve and arc, which rotate smoothly with a
certain clearance maintained between each other and inside wall of the casing.
The inhaled gas to be fed under pressure is smoothly pressurized against the pressure gas on the discharge
side. The pump is so constructed as to allow no oil to be mixed in the discharge gas. The power of motor is
transmitted to the main Screw shaft through a coupling device, and further to the driven Screw shaft through a
timing gear.
1.2 Construction
●
Screw Shaft
The Screw shaft is made of high grade spheroidal graphite cast steel, and precision machined through
numerical control by a special machine. It has a perfect dynamic balance testing after the Screw is machined.
●
Timing Gear
The timing gear is the most important part of the screw vacuum pump, and it is necessary for turning the
Screws with a certain clearance kept from each other. The tooth surface is heat cured, and then polished with
a special high precision tooth-polishing machine for lowering of noise.
●
Bearing
The bearing on fixed side is an angular contact ball bearing and that on expansion side is a roller bearing of
heavy load capacity. These bearings have been selected as to stand high speed and heavy load service and
to assure the accurate keeping of the clearances between gears and between Screws.
●
Shaft Seal
The shaft seals consist of Triple Lip Seals & slingers on Suction side, Bellows type Mech. Seal on Discharge
side. These Seals prevent oil from Front End Plate to inside of Casing. Front End Cover side of drive shaft is
sealed by an Oil seal.
●
Oil Level Gauge
Oil Level Gauge is located at Front End Cover. Oil should be supplied to the top level of Red mark. If the oil
level is too low, Gear, Bearing and Mechanical Seal will be damaged as a result of improper lubrication. So,
when pump is not in use, be sure to check the oil level and contamination, and then, refill or change the oil
when needed. The oil is splashed over by rotation of timing gear and lubricates bearings and Mechanical
seals.
