9
Section 3: OPERATION
3.10
Starting Procedures
3.11
Starting a Welch Dry Vacuum Pump
Before attaching the pump to a system it is well to familiarize yourself with the function and action of
the pressure vacuum pump that you have acquired. Review the power requirements as described in
Section 2.6. Welch recommends running the pump for a few minutes to warm up before use. The
warm-up improves the pump’s ability to handle humid air.
3.12
Cleanliness
Take every precaution to prevent foreign particulates from entering the pump. Particulates will damage
the pump’s performance. If you fi nd that particulates will come off the process during evacuation, a
particle trap in the foreline will work. A simple, inexpensive trap may be made by placing glass wool in
a glass or plastic tube. Screens must be inserted to hold the glass wool in place.
3.13
Leak Detection
The importance of eliminating all leaks in a vacuum system is obvious. The pump must remove this
added volume of leaked gas to maintain the desired vacuum. Leaks for these pumps can be located by
slightly pressuring the system and painting the suspected area with a thick soap solution. Escaping air
will produce soap bubbles.
3.14
Operating Pressure Range
Model 2581 Dry Vacuum Pumps are designed to be run from atmospheric to their maximum vacuum
level on the intake side. Consult the Specifi cation Table in the back of this manual for the ratings for
your specifi c model.
3.15
Shutdown Procedures
After use, Welch recommends the pump be run for about 2 minutes disconnected from the vacuum
process. The air pumped through the mechanism will purge out water vapor or droplets of water
condensate that may have formed on the inside of the pump. This purge of the pump mechanism helps
prevent corrosion.
Section 4: MAINTENANCE
Welch dry pressure\vacuum units are 100% oil-free. The pump employs a non-lube piston and cylinder.
No maintenance is necessary for the bearings. All bearings are sealed and permanently lubricated.
Lubrication should not be attempted. The units are built for continuous duty operation with the
quietness and durability of a diaphragm, but with piston pump performance.
WARNING
The Pump is not recommended for pumping acid, base or organic
vapors or gases. Serious damage to the pump will shorten the
pump’s service life.In addition, pumping flammable vapors or
gases can lead to serious safety hazard leading to fire or explosion.
Summary of Contents for Welch 2580B-01
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