Contents
Varian Vacuum Technologies 121 Hartwell Avenue Lexington, MA
HS-20 Diffusion Pump
Instruction Manual
781861-7200
Avda Pedro Diez
Sales and Service Offices
716 Yishan Road Shanghai
Continental U.S. only - 1-800-8-VARIAN
Telephone Numbers
FAX Numbers
Hawaii and Alaska
3/5/97
Warranty
Warranty Replacement and Adjustment
OPERATION AND MAINTENANCE OF THIS EQUIPMENT INVOLVES SERIOUS RISK. IT IS THE RESPONSIBILITY OF THE USER TO MAINTAIN SAFE OPERATING CONDITIONS AT ALL TIMES. VARIAN ASSUMES NO LIABILITY FOR PERSONAL INJURY OR DAMAGE RESULTING FROM OPERATION OR SERVICE OF THE EQUIPMENT
SAFE INCORPORATION OF VARIAN DIFFUSION PUMPS INTO VACUUM SYSTEMS IS THE RESPONSIBILITY OF THE SYSTEMS DESIGNER. TAKE APPROPRIATE ACTION THROUGH REDUNDANCY, AND/OR OTHER SAFEGUARDS TO PROTECT PERSONNEL AND PROPERTY FROM THE HAZARDS DESCRIBED BELOW AND IN THE INSTALLATION, OPERATION, AND MAINTENANCE INSTRUCTION MANUAL. SAFE OPERATION IS THE RESPONSIBILITY OF THE USING ORGANIZATION AND ITS PERSONNEL. READ THE INSTRUCTION MANUAL AND UNDERSTAND HOW TO AVOID HAZARDS PRIOR TO OPERATING THE DIFFUSION PUMP. ALL PERSONS WHO WORK WITH OR ARE EXPOSED TO DIFFUSION PUMPS OR EQUIPMENT WHICH UTILIZES SUCH PUMPS OR DIFFUSION PUMP FLUID MUST TAKE PRECAUTIONS TO PROTECT THEMSELVES AGAINST POSSIBLE SERIOUS BODILY INJURY OR DEATH. DO NOT BE CARELESS AROUND SUCH PRODUCTS
Loss of utility water and/or electricity
Three elements are required fuel, oxidizer, and source of ignition. A combination of temperature and pressure can be a source of ignition. Most diffusion pump fluids except mercury are fuels. Hydrocarbon oils are more prone to oxidize and explode than synthetic silicone-based oil. Oxidizer can be air a strong oxidizer from a leak or can be deliberately introduced in a process or can be inadvertently admitted to the system by operator or process controller error. Oxygen and other strong oxidizers are even more dangerous. Certain conditions of temperature and pressure can cause a combustible mix- ture to explode. The larger the diffusion pump, the greater the risk of explosion and the greater the risk of damage and/or injury. Never operate diffusion pumps larger than 10 inches in diameter with hydro- carbon oils without a complete safety analysis for the complete system and application. Never operate any diffusion pump in the following ways because they increase the probability of an explosion
Contaminate pump with explosive vapors
d. Poisonous and/or Corrosive Compounds - When pumping poisonous, reactive, and/or corro- sive gas, vapors, or chemicals, even proper operation and regeneration will not always ensure that all hazardous materials have been totally removed. If hazardous gas, vapors, chemicals, or combustible mixtures are pumped, sufficient quantities may exist during operation or remain after regeneration to cause severe injury or death. Overheating the pump oil, exposing it to air or reac- tive materials, or overpressurizing it above the normal operating range approximately 1 mTorr .133 Pa will decompose the oil and possibly make it toxic. This is especially true of back- streamed mechanical pump oils which are more volatile unstable. Overheating of accidentally introduced or backstreamed mechanical pump oils cannot be protected against by thermal switch- es which are set for diffusion pump oil
i. Cold Coolant - Liquid nitrogen, a cryogenic liquid, is used in traps. If it is splashed on body tis- sues or eyes, it can cause severe frostbite or blindness. The extremely low temperature of lique- fied nitrogen can cause skin damage similar to high temperature burns. Contact with the cold gas evolving from the liquid may produce the same effect. Delicate tissues, such as the eye tissues, are most easily damaged by exposure to cold gas or liquid. To minimize the risk of hazardous con- tact of cold gaseous nitrogen with any part of the body, wear personal safety equipment recom- mended for use with cryogenic materials including face shield, full-sleeved lab coat, and clean, dry gloves which fit loosely so they can be thrown off quickly if frozen by contact with the gas
Page
Page
Section I - Installation
Table of Contents
Safety Considerations
Section
List of Illustrations
List of Tables
Technical Specifications
INSTALLATION 1-1 GENERAL
1-2 OPERATING SPECIFICATIONS See Figure
SECTION
Switches
Installation
PHYSICAL SPECIFICATIONS See Figure
Weight
Installation
Figure 1-2. Outline Drawing - HS-20 Diffusion Pump, with ASA Flanges
Installation 1-4 UNPACKING
1-5 CLEANING A NEW PUMP
Installation
1-6-2 Vacuum Connections
Installation 1-6 UTILITY AND SYSTEM CONNECTIONS
1-6-1 Safety Considerations and Interlocks
1-6-3 Cooling Water Connections See Figure
Installation
Figure 1-3. Cooling Water Connections
Installation
1-6-5 Thermal Switches
1-6-6 Initial Vacuum Test
Installation
1-10
Installation
Figure 1-5. 380/415 V Wiring Diagram - HS-20 Diffusion Pump
Pumps and their components are designed for vacuum service they are not designed to be pressurized which could cause them to burst possibly expelling shrapnel at lethal velocities. Serious accidents have been caused by intentional pressurization of vacuum systems and their components. Never pressurize any part of a vacuum system for test or any other purpose. Always provide pressure relief when designing diffusion pumps into systems and ensure that pressure relief motion is limited to safe envelopes
1-7 ADDING PUMP FLUID
Installation
Installation
Figure 1-6. Sight Glass Assembly
SECTION
2-1 START-UP PROCEDURE
OPERATION
2-2 SHUTDOWN PROCEDURE
Operation
SECTION
MAINTENANCE 3-1 GENERAL
3-2 PERIODIC INSPECTION
Maintenance
3-3 CLEANING
Maintenance
3-4 DISASSEMBLING AND REASSEMBLING THE COLD CAP Refer to Figure
Do not overtighten the screw
c. Drain the pump of all fluid
Maintenance
Figure 3-1. External Fittings - Cold Cap Assembly
3-5-2 Disassembling the Lower Jet Assembly
Maintenance 3-5 JET ASSEMBLY
3-5-1 Disassembling the Jet Assembly Refer to Figure
Maintenance
Figure 3-2. 20-inch Jet Assembly
3-6 HEATER REPLACEMENT
Maintenance 3-5-3 Reassembling the Lower Jet Assembly
3-5-4 Reassembling the Jet Assembly
Maintenance
Figure 3-3 Jet Coupling
Tighten clamping nuts to 250 in.-lbs
Maintenance
Figure 3-4. Heater Element Assembly
Maintenance
Part Number
3-7 REPLACEABLE PARTS
Maintenance
Description
Maintenance
3-12
4-3 POOR PUMP OR SYSTEM PERFORMANCE
TROUBLESHOOTING 4-1 LEAKAGE
4-2 OUTGASSING
SECTION
Troubleshooting
Table 4-1 Troubleshooting Cont’d
