Connections; V-Belt Drive; Coupling Drive; Preparation For Operation - Rietschle TWISTER VSA Serie Manual De Instrucciones

4.3 Connections

4.3.1 V-belt drive

The lives of belt and bearings greatly depend on the belt ten-
sion. If the belt tension is too loose, reduction of transmission
efficiency due to belt slip, and fatigue and heating of belts will
be considerable, which can make the belt life significantly
shorter and damage bearings as a result of belt vibration.If
belts are too tight, too much tension will be applied and belts
will be weakened and bearing damage may occur. Therefore,
adjust the belt tension properly as shown below.
Apply a below listed load vertically at the centre of "l".
The deflection at this time is e = 0.016 x l (mm).
Load in belt tension, F (N)
Type A B
New belt 10 18
Re-tensioning 13 25
After adjusting, run the pump for few days.. Then re-adjust the
belt tension with the same procedure.

4.3.2 Coupling drive

Align coupling by using Dial Gauge. The concentricity should
be as follows:
Motor Pump
side side
Feeler gauge
Class of motor
M180
M200M and above
Class of motor
M132M and under
M160M and above
C D 3V 5V 8V
39 78 25 77 212
54 98 36 102 271
Motor Pump
side side
On side of coupling
less than 0.05
less than 0.08
At end of coupling
less than 0.1
less than 0.18

4.4 Preparation for operation

• Remove dust from Vacuum Pump and piping. Clean the
pipework thoroughly, ensuring welding slag and debris etc.
are removed.
• Check all suction and discharge connections are properly
tightened and all the piping is properly supported. Also
check cooling water piping.
• Supply oil up to the red mark of the oil gauge. If oil level is
low, gear and bearings can seize, and if oil level is too
high, the temperature will rise excessively, and can be the
cause of gear noise or some effect on other parts.
• Cooling water flow to be as specified in chart 1.3.
4.5 First Operation
Warning –> Start-up with pipework
At start-up, severe damage may occur if there is debris in
the pipework.
We therefore recommend a vacuum tight inlet filter of 5
micron rating is installed for start-up.
• With suction valve closed, run the motor briefly to check
direction of rotation, correct if required.
• Run the pump under no load condition for 20-30 minutes
to check for any abnormal vibration or heat. In case of any
abnormality, stop the pump and search for the cause. In
most cases, the cause is improper installation or coupling
centring. Check for correct lubricant level.
• Run the pump for 2 - 3 hours under normal load condition
and check the temperature and vibration of each parts.
• During operation, pay attention to indication of motor am-
pere Meter. If any abnormality is found, stop the pump
immediately and check the cause. Often, the cause is in-
terference between rotors or between the periphery of ro-
tor and the inner surface of casing. All pumps are factory
run before despatch, however, full care will be still neces-
sary after the pump installed on site.
* Caution during Operation:
• Check temperature of bearing & lubricant and indication
of Ampere meter & cooling water.
• Keep operation within designated specifications.

4.6 Stopping

• Shut suction valve.
• If any corrosive gas, solvent or water vapour has been
pumped, introduce atmospheric air ( or N
side for 20-30 minutes before stopping to clean the pump
internals. If a solvent or steam cleaning purge is used, run
the pump for 10 minutes on air or N
solvent has been turned off.
• Stop the pump by turning off the motor.
• Shut off cooling water. If freezing is anticipated, discharge
water by opening of drain valves.

4.7 Lubrication

Lubricants to be used must be good and high grade petro-
leum products containing oxidation inhibitor, rust preven-
tive, extreme-pressure additive, etc. (Do not use any lubri-
cant which contains any element of water , sulphate resin
or tar.).
Turbine oil (ISO VG 68) readily obtainable in the market
will generally satisfy these requirements.
The following brands are recommended for use as lubri-
cants for gear and bearing.
• Lubricant: BP Energol THHT 68, BP Energol THB 68,
Regal R & O 68, Shell Turbo 68, Mobil Gear 626 or equiva-
lent oils.
• Grease: Aeroshell grease 150, Shell Dorium Grease R,
G 40 M, JFE 552 (NOK-Kluber) or equivalent grease.
- 6 -
) from suction
2
purge only after steam/
2