NOTICE: This document contains references to Varian. Please note that Varian, Inc. is now part of Agilent Technologies. For more information, go to www.agilent.com/chem. vacuum technologies VHS-4, VHS-6 and VHS-250 Diffusion Pumps Part No.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Copyright 2008 Varian, Inc.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps 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 an equitable portion of the purchase price of the Product. Items expendable in normal use are not covered by this warranty.
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Declaration of Conformity Declaration of Conformity Konformitätserklärung Déclaration de Conformité Declaración de Conformidad Verklaring de Overeenstemming Dichiarazione di Conformità We Wir Nous Nosotros Wij Noi Varian, Inc.
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VHS-4, VHS-6 and VHS-250 Diffusion Pumps Contents Introduction ............................................................................................................................... 1-1 Pump Specifications ........................................................................................................................... 1-1 Installation ............................................................................................................................... 1-10 Unpacking ...........
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VHS-4, VHS-6 and VHS-250 Diffusion Pumps Figures 1-1 1-2 1-3 1-4 1-5 1-6 3-1 3-2 3-3 3-4 3-5 3-6 VHS-4 Speed and Throughput Curves .................................................................................. 1-4 VHS-4 Wiring Information ................................................................................................... 1-4 VHS-6 Speed and Throughput Curves .................................................................................. 1-6 VHS-6 Wiring Information .................
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VHS-4, VHS-6 and VHS-250 Diffusion Pumps Tables 1-1 1-2 1-3 1-4 4-1 5-1 5-2 5-3 5-4 5-5 5-6 Pump Operational Specifications ........................................................................................ VHS-4 Dimensions ............................................................................................................. VHS-6 Dimensions ............................................................................................................. VHS-250 Dimensions ........................
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VHS-4, VHS-6 and VHS-250 Diffusion Pumps Preface Instructions for Use This equipment is designed for use by professionals. Read this instruction manual and any other additional information supplied by Varian before operating the equipment. Varian will not be held responsible for any events that occur due to non-compliance with these instructions, improper use by untrained persons, non-authorized interference with the equipment, or any action contrary to that provided for by specific national standards.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Safety Diffusion Pump Hazards Designers of systems utilizing diffusion pumps must design out hazards wherever possible. For hazards that cannot be designed out, warnings, procedures, and instructions on proper use and servicing are provided. Please use guards, safety features, and interlocks as recommended.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps General Hazards 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. Overpressure in foreline Provide an interlock to ensure that the power supply to the pump heater cannot be activated if the foreline pump is not running and/or the pressure in foreline is above 0.5 Torr (0.67 mbar).
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Explosion Operation of the diffusion pump without continuous evacuation below 0.5 Torr (0.67 mbar) or without coolant, and then introducing a strong oxidizer (such as air), explosive vapors, powders, or materials which may react with pumping fluids in a hot pump (above 300 °F or 150 °C) can cause an explosion.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Explosive Conditions Prohibited Action Explosion-Causing Condition Do not run pump without cooling water. Overtemperature Do not run pump with low level of pump fluid. Overtemperature Do not run pump without proper backing or holding pump. Overpressure Do not run pump when not evacuated below 0.5 Torr (0.67 mbar). Overpressure Do not admit air to, or rough through, a pump with hot boiler.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Pressurization Hazards Large vacuum pumps and their components are designed for vacuum service. They are not designed to be pressurized, which can cause them to burst and possibly expel 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.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Dangerous Substances Chemical Dangers of Acetone and Alcohol Diffusion pumps are typically cleaned with acetone or alcohol. Acetone, alcohol, and most other solvents are irritants, narcotics, and depressants, and/or carcinogenic. Their inhalation and ingestion may produce serious effects. Even absorption through the skin can result in moderate toxicity. Ensure that cleaning operations are always performed in large, well-ventilated rooms.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps High Temperatures Hot Surfaces Boiler temperatures reach 530 °F (275 °C) which can cause serious burns. Always ensure that surfaces have cooled to near room temperature before touching them. Hot Cooling Water and Steam The water used to cool the pump can reach scalding temperatures. Touching or rupturing the cooling surface can cause serious burns. Water left inside Quick Cool Coils from previous use turns to steam when the pump is reheated.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Section 1. Introduction and Installation 1.1 Introduction Before unpacking and installing a VHS-4, VHS-6 or VHS-250 diffusion pump, thoroughly familiarize yourself with this instruction manual and the diffusion pump operational specifications (Table 1-1). Examine all other technical material supplied in order to gain a better understanding of the operating principles, limitations, correct application, and hazards involved with the operation of this equipment. 1.1.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Table 1-1 Pump Operational Specifications (Continued) Backstreaming Rate at Pump Inlet 5x10−4 mg/cm2/minute (with std cold cap) Electrical Requirements 120, 208, 240; 50/60 Hz; single phase Warm-up Time 10 minutes Cooldown Time (using Quick Cool Coil) 10 minutes Fluid Charge VHS-4: 300 cc VHS-6 and VHS-250: 500 cc Cooling Water Requirements Maximum inlet temperature – 60/80 °F (15 - 26 °C) Maximum outlet temperature at foreline – 120 °F (48.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Table 1-1 Heater circuit resistance (ohms) Pump Operational Specifications (Continued) VHS-4: 1450 watts 120 V – 10 208 V – 29.8 240 V – 39.7 VHS-6 and VHS-250: 2200 watts Clearance (for heater removal) 6" minimum Materials Body, Flanges, Foreline, Baffle – stainless steel Jet Assembly – stainless steel Body Cooling Coils – copper Quick Cooling Coil – stainless steel Cold Cap – nickel-plated copper Shipping Weight VHS-4: 55 pounds DRAFT 1/23/08 120 V – 6.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Figure 1-1 shows the VHS-4 speed and throughput curves. Speed with standard cold cap 5 1200 4 900 3 600 2 300 1 0 10−10 10−9 10−4 10−7 10−10 10−5 10−4 10−3 10−2 10−1 Throughput (Torr-//sec) Air Speed (//sec) Speed with extended cold cap 1800 0 DRAFT 1/23/08 INLET PRESSURE — TORR *Note: Speed curves were generated according to AVS Standards 4.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Table 1-2 lists the VHS-4 dimensions. VHS-4 Dimensions ASA ISO Conflat in mm in mm in mm Height 18.05 458 18.05 458 18.05 458 Centerline to Centerline 10.62 270 10.62 270 10.62 270 Flange Face to Flange Face 5.03 128 5.03 128 5.03 128 EIectrlc8I Box Height 8.63 219 8.63 219 8.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Figure 1-3 shows the VHS-6 speed and throughput curves. DRAFT 1/23/08 Figure 1-3 VHS-6 Speed and Throughput Curves Figure 1-4 gives the VHS-6 schematic and wiring information.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Table 1-3 lists the VHS-6 dimensions. VHS-6 Dimensions ASA ISO Conflat in mm in mm in mm Height 21.92 557 21.92 557 21.92 557 Centerline to Centerline 13.38 340 13.38 340 13.38 340 Flange Face to Flange Face 8.62 219 8.62 219 8.62 219 EIectrlc8I Box Height 9.12 232 9.12 232 9.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps DRAFT 1/23/08 Figure 1-5 shows the VHS-250 speed and throughput curves. Figure 1-5 VHS-250 Speed and Throughput Curves Figure 1-6 gives the VHS-250 schematic and wiring information.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Table 1-4 lists the VHS-250 dimensions. Table 1-4 VHS-250 Dimensions in mm Height 22.79 579 Centerline to Centerline 13.38 340 Flange Face to Flange Face 9.56 243 Electrical Box Height 9.12 232 Sight Glass, Degrees from Foreline 90° clockwise Electrical Box, Degrees from Foreline 30° counterclockwise Inlet Flange, Nominal Size ISO - 250F Inlet Flange, OD 13.19 335 Inlet Flange, ID 10.75 273 Inlet Flange, Thickness 0.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps 1.2 Installation Installation consists of: ❑ Section 1.2.2 “Unpacking” ❑ Section 1.2.3 “Pump Oil Installation” ❑ Section 1.2.4 “Vacuum System Connections” on page 1-11 ❑ Section 1.2.5 “Cooling Water Connections” on page 1-11 ❑ Section 1.2.6 “Electrical Connections” on page 1-12 ❑ Section 1.2.7 “Thermal Switch” on page 1-13 1.2.2 Unpacking When unpacking the pump: DRAFT 1/23/08 1. Inspect the pump to ensure that no damage has occurred during shipping.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps 1.2.4 Vacuum System Connections WARNING Utility failure can cause damage to the equipment, overheating, and explosions. Diffusion pump equipment designers must take appropriate system design action to protect personnel and property from possible hazards. Read the safety section at the beginning of this manual. 1. Install the diffusion pump with the body vertical and plumb. 2. Ensure that the pump inlet mating flange on the system is horizontal within ±1°.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps ❑ The minimum rating of this system should be 85% of the maximum power rating of the diffusion pump. ❑ The Quick Cool Coil feed line, located at the boiler plate, should be controlled by a separate three-way valve (open, closed, and vent to atmosphere). 2.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps 1.2.7 Thermal Switch The pump has been fitted with a manually-resettable thermal switch that is preset at the factory. This switch is located in a box near the bottom of the pump and provides protection to the pump in the event of excessive fluid loss, the loss of cooling water, or high inlet pressure. WARNING ❑ Failure to properly connect the thermal switch circuit can result in catastrophic injury to personnel and major damage to the pump or vacuum system.
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VHS-4, VHS-6 and VHS-250 Diffusion Pumps Section 2. Operation CAUTION ❑ Before turning on the heater, ensure there is fluid in the pump. Running the heater without fluid can ruin the heater and damage the pump. ❑ Do not air-release the pump while the boiler is hot. Most diffusion pump fluids are heat sensitive and breaks down under these conditions. ❑ Do not operate the pump without the internal splash baffle or foreline baffle in place.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps 5. Monitor inlet and foreline pressures. During operation of the diffusion pump: ❑ The gas load at the inlet should not exceed the maximum throughput capability of the pump. ❑ The forepressure should not exceed the specified tolerable forepressure. 2.2 Shutdown 1. Turn off the power to the diffusion pump and continue to back the diffusion pump with the appropriate mechanical pump. 2.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Section 3. Maintenance and Service 3.1 General Maintenance Diffusion pumps generally require little attention when operated correctly. It is advisable to perform some periodic inspections to ensure trouble-free operation. By performing simple preventive maintenance, costly downtime can be avoided. A day-to-day log of pump and system performance helps indicate the condition of the pump and the need for corrective action.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps ❑ Ensure that the cooling water flow is adequate and unobstructed. In areas where the mineral content of the water is high or where there is considerable sediment, it may be advisable to install water filters. 3.3 Cleaning Complete cleaning of the pump may be required due to the gradual deterioration of pump fluids. Removal of the pump from the system is necessary. To clean the pump: 1. Turn off the power and disconnect the power supply plug. 2.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps 3.4 VHS-4 and VHS-6 Cold Cap Removal/Installation To remove the cold cap: 1. Remove the spring (1) (Figure 3-1) attached by round head screw (2), a flat washer (3) and a lock washer (4). The screw types are: ❑ VHS-4: no. 8-32x3/16 ❑ VHS-6: no. 6-32x3/16 2. Loosen the nut (5) holding the cold cap bracket (6) to the copper bar (A) and remove the cold cap (7) from the top of the jet cap (8). 3. Unscrew the no.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps 3.5 VHS-250 Cold Cap Removal/Installation To remove the cold cap: 1. Remove the spring (J) attached by the 6-32x3/16 round head screw (H), a flat washer and a lock washer (Figure 3-2). 2. Loosen the nuts (L) holding the cold cap bracket (E) to the copper bar (C) and remove the cold cap (B) from the top of the jet cap (A). 3. Unscrew the no. 8-32x1/4 socket head cap screw (G) from the top of the ceramic standoff (D). 4. Remove the ceramic standoff (D) and the no.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps 3.6 Jet Assembly Removal/Installation To remove the jet assembly: 1. Remove the cold cap from the pump (Figure 3-3). 2. Unscrew the top cap from the jet assembly. 3. Lift out each section of the jet assembly, being careful not to dent or otherwise damage the jet assembly during disassembly or cleaning. 4. Remove the splash baffle from the pump. To install the jet assembly: 1.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Jet Cap Jet Plug Inner Rod 2nd Stage Drip Shield 3rd Stage Jet 3rd Stage Drip Shield DRAFT 1/23/08 Jet Tube Assembly Jet Base Ejector 4.
DRAFT 1/23/08 VHS-4, VHS-6 and VHS-250 Diffusion Pumps Figure 3-4 VHS-6 and 250 Diffusion Pump Jet Assembly 3-7
VHS-4, VHS-6 and VHS-250 Diffusion Pumps 3.7 Heater Replacement Refer to Figure 3-5 (VHS-6 and VHS-250) and Figure 3-6 (VHS-4) for this procedure: 1. Turn off the power to the diffusion pump and disconnect the power supply. 2. Remove the heater cover and the insulation from the bottom of the diffusion pump. 3. Label the heater wires for proper location during installation. 4. Disconnect the terminal leads.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Heater Element Figure 3-6 DRAFT 1/23/08 647304205 1450 W, 120 V 647304210 1450 W, 208 V 647304250 1450 W, 240 V VHS-4 Heater Mounting 3-9
VHS-4, VHS-6 and VHS-250 Diffusion Pumps 3.8 Pump Fluid Charge The recommended fluid charge is: ❑ 300 cc for the VHS-4 ❑ 500 cc for VHS-6 and VHS-240 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 fill amount, the boiler plate temperature may begin to rise. Under this condition, the thermal switch, when properly connected, is designed to open the heater circuit.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Section 4. Troubleshooting 4.1 Leakage ❑ Inlet and foreline connections ❑ Drain and fill plugs ❑ Other compression fittings, such as high vacuum gauges in the system ❑ Threaded connections, such as foreline gauge 4.2 Outgassing High vacuum systems, even without external leakage, can also exhibit high gas loads due to outgassing from internal surfaces or processes. The pressure in the system is a result of gas load divided by pumping speed (P = Q/S).
VHS-4, VHS-6 and VHS-250 Diffusion Pumps 4.3 Poor Pump or System Performance Before proceeding with a step-by-step troubleshooting program, check the performance and accuracy of the vacuum gauges used on the system. Table 4-1 shows the most frequent faults, their probable causes, and specific repair actions required for each. Table 4-1 Symptom Poor system pressure DRAFT 1/23/08 Poor ultimate pressure Troubleshooting Probable Cause Repair Action Leak in system — virtual or real. Locate and repair.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Table 4-1 Inlet pressure surges High chamber contamination Pump will not start Probable Cause Repair Action Incorrect heater voltage. Check and correct voltage. Fluid outgassing. Condition pump fluid by operating pump for a few hours. Leak in system ahead of pump inlet. Check and correct. Forepressure too high. Check for leak in foreline, poor mechanical pump performance, breakdown of pump fluid, and incorrect valve operation.
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VHS-4, VHS-6 and VHS-250 Diffusion Pumps Section 5. Replacement Parts Table 5-1 lists the VHS-4 models. Table 5-2 lists the VHS-4 replacement parts available from Varian.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Table 5-2 VHS-4 Replacement Parts (Continued) 88164301 Heater Clamp Commercial Heater Clamp Nut, 31/48-16, Hex, stainless steel 694492156 Baffle Retaining Ring K0377183 O-Ring Kit includes: ❑ 3 Butyl inlet flange O-ring, Parker No. 2-258 ❑ 10 Viton fill and drain O-rings (old style), Parker No. 2-112 ❑ 10 Viton fill and drain O-rings (new style, Parker No. 2-113 ❑ 1 Sight glass O-ring, Parker No.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Table 5-4 VHS-6 Replacement Parts Description 86488301 Standard Cold Cap Assembly F6455301 Extended Cold Cap Assembly F3365301 Jet Assembly F3373301 Splash Baffle L9172301 Foreline Baffle Assembly 642906025 Thermoswitch 699006025 Standoff, ceramic insulating, Cold Cap 647306125 120 V / 2200 watt Heater Element 647306175 208 V / 2200 watt Heater Element 647306225 240 V / 2200 watt Heater Element 656179100 Wire, No.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Table 5-4 VHS-6 Replacement Parts (Continued) Commercial Washer, flat, no. 6, stainless steel Commercial Washer, lock, no. 6, stainless steel Commercial Stud, no. 8-32 x 1/2, stainless steel Commercial Screw, Socket hd cap, no. 8-32x1/4, stainless steel Table 5-5 lists the VHS-250 models. Table 5-6 lists the VHS-250 replacement parts available from Varian.
VHS-4, VHS-6 and VHS-250 Diffusion Pumps Table 5-6 VHS-250 Replacement Parts (Continued) 86088301 Heater Cover Plate L8998001 Heater Insulating Blanket L8997001 Heater Cover K0377178 O-Ring Kit includes: ❑ 3 Butyl inlet flange O-ring, Parker No. 2-332 ❑ 3-Butyl-N foreline flange O-ring, Parker No. 2-379 ❑ 10 Viton fill and drain O-rings (old style), Parker No. 2-112 ❑ 10 Viton fill and drain O-rings (new style, Parker No.
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Request for Return Health and Safety Certification ISO Request for Return Health and Safety Certification 9001 R E G I S T E R E D 1. Return authorization numbers (RA#) will not be issued for any product until this Certificate is completed and returned to a Varian, Inc. Customer Service Representative. 2.
Request for Return Health and Safety Certification ISO 9001 R E G I S T E R E D FAILURE REPORT (Please describe in detail the nature of the malfunction to assist us in performing failure analysis): TURBO PUMPS AND TURBOCONTROLLERS Claimed Defect ❒ Does not start ❒ Does not spin freely ❒ Does not reach full speed ❒ Mechanical Contact ❒ Cooling defective Describe Failure: ❒ Noise ❒ Vibrations ❒ Leak ❒ Overtemperature ❒ Clogging Position ❒ Vertical ❒ Horizontal ❒ Upside-down ❒ Other ....................
Sales and Service Offices Sales and Service Offices Canada Central coordination through: Japan Varian, Inc. Other Countries Varian, Inc. Varian, Inc. 121 Hartwell Avenue Lexington, MA 02421 USA Tel: (781) 861 7200 Fax: (781) 860 5437 Toll Free: (800) 882 7426 Sumitomo Shibaura Building, 8th Floor 4-16-36 Shibaura Minato-ku, Tokyo 108 Japan Tel: (81) 3 5232 1253 Fax: (81) 3 5232 1263 Via F.
