Varian Vacuum Technologies 121 Hartwell Avenue Lexington, MA 02421 (781)861-7200 HS-20 Diffusion Pump Instruction Manual Manual No.
Sales and Service Offices America Varian Vacuum Technologies 121 Hartwell Avenue Lexington, MA 02421, USA Tel: (781) 861 7200 Fax: (781) 860 5437 Toll Free: 1 (800) 882 7426 France Varian s.a. 7 avenue des Tropiques Z.A. de Courtaboeuf – B.P. 12 Les Ulis cedex (Orsay) 91941 France Tel: (33) 1 69 86 38 38 Fax: (33) 1 69 28 23 08 Argentina Varian Argentina Ltd. Sucursal Argentina Av.
Telephone Numbers For technical support and service within the continental United States, Alaska and Hawaii: Continental U.S. only – 1-800-8-VARIAN (1-800-882-7426) Order Entry (Sales) ..............................................................................Press 1 Technical Support and Field Service....................................................Press 2 Training (Information and Registration) .........................................
Warranty Products manufactured by Seller are warranted against defects in materials and workmanship for twelve (12) months from date of shipment thereof to Customer, and Seller’s liability under valid warranty claims is limited, at the option of Seller, to repair, replacement, or refund of an equitable portion of the purchase price of the Product. Items expendable in normal use are not covered by this warranty.
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. Carelessly or improperly operated equipment can cause serious injury or death and/or damage to 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.
THE INSTALLATION, OPERATION, AND/OR SERVICING OR DIFFUSION PUMPS INVOLVES ONE OR MORE OF THE FOLLOWING HAZARDS, ANY ONE OF WHICH, IN THE ABSENCE OF SAFE OPERATING PRACTICES AND PRECAUTIONS, COULD POTENTIALLY RESULT IN DEATH OR SERIOUS HARM TO PERSONNEL. Hazard Suggested Corrective Action Loss of utility: water and/or electricity Provide sufficient backup water and power supply as necessary to effect a safe shutdown under worst case conditions.
Hazard Suggested Corrective Action a. Explosion – Operation of the diffusion pump without prior and continuous evacuation (below 0.5 Torr (66.5 Pa)) or coolant and introducing a strong oxidizer (such as air) or explosive vapors or powders or materials which may react with pumping fluids into a hot (above 300°F or 150°C) pump can cause an explosion.
Prohibited Action Explosion-Causing Condition Contaminate pump with explosive vapors, powders, or reactive materials Lower explosive threshold of gas mixtures Remove, defeat, or override safety countermeasures such as pressure and thermal switches and valve sequencer interlocks Overtemperature, overpressure, more combustible mixtures Machine or weld without removing all oil or solvent residue in pump Source of ignition Use unsuitable pumping fluid especially in large pumps Lower explosive threshold
d. Poisonous and/or Corrosive Compounds – When pumping poisonous, reactive, and/or corrosive 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.
i. Cold Coolant – Liquid nitrogen, a cryogenic liquid, is used in traps. If it is splashed on body tissues or eyes, it can cause severe frostbite or blindness. The extremely low temperature of liquefied 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.
WARNING _____________ High voltages (up to 480 V) can kill. Always break the primary circuit to the power supply before starting to work on the heater and/or its wiring. WARNING _____________ Diffusion pumps are typically cleaned with acetone, alcohol, or other solvents. When heated, sprayed or exposed to high temperature equipment, these solvents become flammable and explosive, causing serious injury or death. Do Not Use Near A High-Temperature Source.
WARNING _____________ If hazardous gas, vapors, chemicals, or combustible mixtures are pumped, sufficient quantities may exist during operation. This pump may contain decomposed and/or overheated pump oils or poisonous and/or corrosive process materials which are highly toxic and also can be an asphyxiant. Proper operation will not always ensure that all hazardous materials have been removed. WARNING _____________ Hot oils can cause serious burns.
Table of Contents Section Page Safety Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i Section I – Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 1-1 1-2 1-3 1-4 1-5 1-6 1-7 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 Operating Specifications . .
List of Illustrations Figure 1-1 1-2 1-3 1-4 1-5 1-6 3-1 3-2 3-3 3-4 Title Speed and Throughput Curves – HS-20 Diffusion Pump . . . . . . . . . . . . . . . . . . . . . . . . . . Outline Drawing – HS-20 Diffusion Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cooling Water Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200/240/400/430/440/480 V Wiring Diagram – HS-20 Diffusion Pump . . . . . . . . . . . . . .
SECTION I INSTALLATION 1-1 GENERAL Upon receipt, inspect the container for evidence of damage in shipment. Do not discard any evidence of rough handling. Factory packing provides for maximum protection during shipment. However, the pump should be inspected immediately and any damage should be reported to the carrier without delay.
Installation Figure 1-1. Speed and Throughput Curves – HS-20 Diffusion Pump 1-3 PHYSICAL SPECIFICATIONS (See Figure 1-2) Flange dimensions (inches): ASA OD ID Thickness Bolt Circle No. of Holes Size of Holes Orientation Gasket Groove ID wide deep Height Inlet Foreline 27.50 9.0 21.25 5.06 1.12 0.75 25.0 7.5 20.0 8.0 1.25 0.75 Straddle center line 21.625 5.31 0.48 0.375 0.25 0.
Installation Figure 1-2.
Installation 1-4 UNPACKING Pumps are factory-packaged to permit prolonged storage in suitably protected areas without special precautions. WARNING _____________ When lifting some Varian diffusion pumps, use power-assisted equipment and trained moving/installation personnel to avoid dropping, slipping, and/or overturning the pump and severely injuring personnel. check weight of equipment before lifting and do not stand under equipment being moved. a.
Installation WARNING _____________ Diffusion pumps are typically cleaned with acetone, alcohol, or other solvents. When heated, sprayed or exposed to high temperature equipment, these solvents become flammable and explosive, causing serious injury or death. Do not use near high temperature source. Ventilate working area with a blower and use in large, well-ventilated room.
Installation 1-6 UTILITY AND SYSTEM CONNECTIONS 1-6-1 Safety Considerations and Interlocks a. Large pumps are equipped with two thermal switches. Both thermal switches on the HS-20 diffusion pump are mounted on a thermal strap located on the side of the pump. These thermal switches are supplied normally closed.
Installation The cooling water discharge should, if possible, be connected to an open drain so that cooling water flow can readily be checked. The temperature of the discharged cooling water should not exceed 130°F (54°C). b. The quick-cool coil at the boiler plate must be connected to an open drain and the feed line controlled by a separate water 3-way valve (open, closed, and vent to atmosphere).
Installation 1-6-4 Electrical Connections (See Figure 1-4 and 1-5, Diffusion Pump Wiring Diagram) WARNING _____________ High voltages (up to 480V) can kill. Always break the primary circuit to the pump before starting to work on the heater and/or its wiring. a. The pump heater has been designed to operate at a certain voltage. Check the heater for correct supply voltage and, in the case of multiphase connections, for load balance by measuring the resistance of each branch.
Installation Figure 1-4.
Installation Figure 1-5.
Installation WARNING _____________ 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.
Installation a. The recommended fluid charge for the pump is five U. S. quarts. The fluid charge will gradually be depleted through use, but the pump will continue to operate normally. When the charge is reduced to approximately 60% of the initial amount, the boiler temperature may begin to rise and under this condition the thermal switch is designed to open the heater circuit. b. This diffusion pump is furnished with fill and drain fittings with special Viton elastomer sealed plugs. c.
SECTION II OPERATION During initial installation, the newly installed pump fluid may be subjected to a degassing process. This may result in foreline pressure fluctuations and "bursts". Such fluctuations are considered normal.
Operation d. Check inlet and forepressure performance by means of the system instrumentation. e. During operation, the gas load at the inlet of the diffusion pump should not exceed the maximum throughput capability of the pump. This means that the pressure at the inlet flange should not (except in transient conditions) exceed approximately 1 x 10-3 Torr (.133 Pa). During operation, the discharge or fore pressure must be below the specified tolerable forepressure.
SECTION III MAINTENANCE 3-1 GENERAL Diffusion pumps generally require little attention when correctly operated. However, it is advisable to perform some periodic checks to insure continued trouble-free operation. By simple preventive maintenance, costly down-time and cleaning procedures can be avoided. A day-to-day log of pump and system performance will indicate the condition of the pump and marked variations will show the need for corrective action.
Maintenance c. When the pump is cold, check that the heaters are bolted snugly to the boiler plate and that all heater terminal connections are tightly fastened inside the junction box. d. Check the total heater input and balance of load if a multi-phase heater is used. e. Check to insure that cooling water flow is unobstructed and not below specified quantities. 3-3 CLEANING Complete cleaning of the pump may be periodically required because of the gradual deterioration of some pump fluids.
Maintenance a. Disconnect all water cooling lines and break the primary circuit supplying power to the pump heaters. b. Unbolt the inlet and foreline connections and remove the pump from the system. c. Drain the pump of all fluid. d. Remove the cold cap and jet assembly following the procedures outlined. e. Thoroughly clean the pump body interior using acetone followed by an isopropyl alcohol rinse. Dry with clean, dry, oil-free compressed air or heat gun. f.
Maintenance Figure 3-1. External Fittings – Cold Cap Assembly NOTE ________ Customer to supply water tubing to be connected to coupling with FPT threads shown above.
Maintenance 3-5 JET ASSEMBLY The HS-20 jet assembly consists of several subassemblies. The lower jet assembly consists of the jet base and stages 3 and 4. A jet shield is provided for the third stage jet. The second stage jet is secured to the central tube and forms a subassembly. A shield is provided for the second stage jet. The top of the central tube carries an orifice plug. The top jet spacer passes through this plug and by a spring-loaded coupling and tie rod secures all stages firmly.
Maintenance Figure 3-2.
Maintenance 3-5-3 Reassembling the Lower Jet Assembly a Carefully replace the fourth stage jet on the jet base. b Replace the third stage jet shield. NOTE ________ Before completing the following step, check that the gaps are even and tighten the screws uniformly and in a cyclic pattern. Jet spacings are preset at the factory and controlled by the spacers secured to respective stages. c Replace and tighten the securing screws between the third and fourth stage jets.
Maintenance Note: If the jet coupling loosens from the jet rod during disassembly, position it so that the top of the jet coupling is flush with the bottom of the orifice plug.
Maintenance Figure 3-4. Heater Element Assembly NOTE ________ Tighten clamping nuts to 250 in.-lbs.
Maintenance WARNING High voltages (up to 480V) can kill. Always break the primary circuit to the power supply before starting to work on the heater and/or its wiring. CAUTION Poor clamping resulting in inadequate thermal contact may result in reduced heater life and poor pump performance. Tighten nuts fingertight on clamping plate, then gradually and evenly tighten them to 250 in-pounds of torque.
Maintenance 3-7 REPLACEABLE PARTS The following is a list of replaceable parts for the Varian HS-20 Diffusion Pump. Part Number 84358301 660811494 F2622001 75786001 622445026 L6367301 84350301 84889301 F6097301 F1755301 77261001 K9050001 K9050002 656118114 648056329 647320025 647320020 647320035 647320040 647320045 647320030 K7108001 K7107001 L6514001 84497001 L9223001 K0377165 695472008 695474008 695475008 Description Cold cap assembly (includes No.10-32 SST Rd Hd screw and No.
Maintenance 3-12
SECTION IV TROUBLESHOOTING 4-1 LEAKAGE Analysis of general operational experience with diffusion pumps indicates that certain locations are more prone to the incidence of leaks. The following locations should be checked first if leakage is the suspected cause of poor system performance. a. Inlet and foreline connections. b. Drain and fill plugs. c. Other compression fittings, such as high-vacuum gauges in the system. d. Threaded connections, such as a foreline gauge.
Troubleshooting Table 4-1 Troubleshooting (Cont’d) Fault Poor ultimate pressure Inlet pressure surges High chamber contamination Pump will not start Probable Cause Corrective Action Contaminated pump fluid Examine and clean pump; replace fluid. Low heat input Check voltage. Check for continuity, burned-out element, poor thermal contact. Inadequate cooling water flow Check water pressure. Check tubing for obstructions and backpressure. Excessive or too cold cooling water Check temperature.