Edwards EXT Series, EXT255Hi, EXT255H, EXT255HVi Instruction Manual

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Instruction Manual

EXT Compound Molecular Pumps:

EXT255H, EXT255Hi and EXT255HVi

B753-03-880

Issue F Original

Description Item Number

EXT255Hi/ISO100 B753-03-000 EXT255H/100CF B753-02-000 EXT255H/ISO100 B753-01-000 EXT255HVi/ISO100 B753-07-000

r?owa,Frtr

Declaration

We, Edwards,

lvlanor Royal, Crawtey,

West Sussex dectare under our sole EXT Compound

EXT?55H/tSO100 Dff255H/100CF DCrz55Hi/lSO100 D(T255H/|SO1 00 Port variant Dff2551-tui

to which this dectaration relates is in conformity with the fottowing standard(s) or other normative documentls):

EN 1SO12100-2: 2003 Safety of machinery. Basic concepts,

EN61010-1: 2001 Etl1O1z-Zt 1997 Compressor: and vacuum

EN6'l3Z6t 19971 Electrical equipment for measurement,

+A1

: 1998 + M: 200'l EMC requirements.

(lndustriat

ctass B Emissions) "

The manual

EN6'1326 lmmunity

for detaits).

RH10 9tW, UK

responsibitity that the

Molecular Pumps:

(Long)

Technicat safety requirements for etectrical equipment for measurement, Control and laboratory use, General requirements.*

Location,

pumps

comply with EN61010-1

supptied with the

ctassification is depeldent on

8753-01-000 8753-m-000

.03

B75r

8753.06-0m/8753-08-000

-07-000

8753

principats.

pumps.

of Conformity

product(s)

{00/875 3-04-000

general principals

(2001)

when instalted in

pumps.

Safety requirements. Vacuum

conttol and laboratory use.

accordance with the

the controtler

(see

the controtler manual

for design.

pumps.

fottowing the

20061951EC Z00/.IIOB|EC ElectromagneticCompatbilityDirective. 98137IEC

furrie Brewster,

provisions

Technical Mandger

This

product

of:

low Voltage Directive.

Machinery Safety Directive.

Burgess Hill

hos been manufqctured

Products

under

2--tlt- C).k,{u>.. Z.a:<>-T

-EJ@7-61'r-

quality

system registered

Date ond Place

to lsogffi1

B753-03-880 Issue F

Section Page

1 Introduction .......................................................................................1

1.1 Scope and definitions ................................................................................................... 1

1.2 General description ..................................................................................................... 2

1.3 Vent options and vent control ......................................................................................... 3

2 Technical data ....................................................................................7

2.1 General .................................................................................................................... 7

2.2 Pumping media ........................................................................................................... 7

2.2.1 Pumps without gas purge ............................................................................................... 7

2.2.2 Pumps with gas purge ................................................................................................... 8

2.3 Vent gas specification and vent control data ....................................................................... 8

2.4 Purge gas specification ................................................................................................. 8

2.5 Cooling-water ............................................................................................................ 9

2.6 Materials exposed to gases pumped .................................................................................11

Contents

3 Installation .................................................... ................................... 15

3.1 Unpack and inspect .....................................................................................................15

3.2 Typical installation .....................................................................................................15

3.3 Connect to the vacuum system .......................................................................................18

3.3.1 Inlet screen ..............................................................................................................18

3.3.2 Mechanical fixing .......................................................................................................18

3.3.3 Base mounting ...........................................................................................................19

3.3.4 Inlet connection and orientation .....................................................................................19

3.3.5 Backing connection .....................................................................................................20

3.3.6 Interstage connection (EXT255Hi/EXT255HVi only) ...............................................................20

3.4 Vent-valve connection and control ..................................................................................20

3.5 Purge gas connection ...................................................................................................21

3.5.1 Connect the purge gas .................................................................................................21

3.5.2 Recommended purge gas flow ........................................................................................21

3.6 Electrical installation ..................................................................................................21

3.7 Cooling ...................................................................................................................21

3.7.1 Introduction .............................................................................................................21

3.7.2 Forced-air cooling ......................................................................................................22

3.7.3 Water-cooling ...........................................................................................................22

4 Operation ........................................................................................ 23

4.1 Start-up ..................................................................................................................23

4.2 Stand-by .................................................................................................................. 23

4.3 Shut-down ................................................................................................................ 24

4.4 Safety interlocks and control system ................................................................................24

4.5 Bakeout ................................................................................................................... 2 4

5 Maintenance ..................................................................................... 27

5.1 Introduction .............................................................................................................27

5.2 Bearing life ..............................................................................................................27

5.3 Rotor life .................................................................................................................27

5.4 Clean the pump .........................................................................................................27

5.5 Fault finding .............................................................................................................28

ITR 22302

B753-03-880 Issue F

Contents

6 Storage and disposal ........................................................................... 31

6.1 Storage ...................................................................................................................31

6.2 Disposal ...................................................................................................................31

7 Service, spares and accessories .............................................................. 33

7.1 Introduction .............................................................................................................33

7.2 Service .................................................................................................................... 33

7.3 Spares .....................................................................................................................33

7.3.1 ISX inlet-screen .........................................................................................................33

7.3.2 Inlet-strainer (EXT255Hi pump only) .................................................................................33

7.3.3 Interstage-port seal (EXT255HVi pump only) .......................................................................34

7.3.4 WCX water-cooler ......................................................................................................34

7.3.5 Inlet-flange seals ........................................................................................................34

7.4 Accessories ............................................................................................................... 3 4

7.4.1 Installation ...............................................................................................................34

7.4.2 EXC controller ...........................................................................................................34

7.4.3 Pump-to-controller cable ..............................................................................................34

7.4.4 EXDC drive modules ....................................................................................................35

7.4.5 BX bakeout band ........................................................................................................35

7.4.6 FL20K foreline trap .....................................................................................................35

7.4.7 TAV vent-valve and vent-port adaptor ..............................................................................37

7.4.8 ACX air-cooler ...........................................................................................................37

7.4.9 Vibration isolators ......................................................................................................37

7.4.10 PRX purge-restrictor ....................................................................................................37

7.4.11 VRX vent-restrictor .....................................................................................................37

For return of equipment, complete the HS Forms at the end of this manual.

Illustrations

Figure Page

1 Cross-section view of EXT255H pump ................................................................................. 4

2 Cross-section view of EXT255HVi pump .............................................................................. 5

3 Maximum allowed rise in backing pressure against time for controlled venting:

system pressure (mbar/Pa) against time (s) ......................................................................... 9

4 EXT255H/EXT255Hi dimensions (mm) ...............................................................................12

5 EXT255HVi dimensions (mm) ..........................................................................................13

6 Typical pumping system with an EXT255H pump ..................................................................16

7 Typical pumping system with an EXT255Hi/EXT255HVi pump ...................................................17

8 Correct installation of the inlet-screen ............................................................................18

9 Installation of optional accessories (and spares): EXT255Hi shown .............................................36

Tables

Table Page

1 Technical data ........................................................................................................... 9

2 Checklist of items .......................................................................................................15

3 Vent-restrictor orifice diameter (with atmospheric pressure at the inlet of the vent-valve) ..............20

4 Fault finding .............................................................................................................28

Edwards and the Edwards logo are trademarks of Edwards Limited.

B753-03-880 Issue F

Associated publications

Publication title Publication number

EXC Turbomolecular Pump Controllers: EXC100E and EXC100L D396-20-880 E2M0.7 Rotary Pump A371-31-880 RV Rotary Vane Pumps A652-01-880

Contents

B753-03-880 Issue F

This page has been intentionally left blank.

Edwards and the Edwards logo are trademarks of Edwards Limited.

B753-03-880 Issue F

CAUTION

WARNING

1Introduction

1.1 Scope and definitions

This manual provides installation, operation and maintenance instructions for the Edwards EXT255H, EXT255Hi and EXT255HVi Compound Molecular Pumps. You must use the Pumps as specified in this manual.

The EXT Compound Molecular Pumps are designed for use with an Edwards EXC Controller. Read this manual and the instruction manual supplied with your EXC Controller before you attempt to install or operate the equipment. The EXC Controller contains details of how to set up a pumping system and how to control acce ssories such as an aircooler, vent-valve and bakeout band.

Important safety information in this manual is highlighted as WARNING and CAUTION instructions; you must obey these instructions. The use of WARNINGS and CAUTIONS is defined below.

Warnings are given where failure to observe the instruction could result in injury or death to people.

Introduction

Cautions are given where failure to observe the instruction could result in damage to the equipment, associated equipment and process

In accordance with the recommendations of EN61010, the following warning symbols may appear on the p ump or its accessories:

Warning - refer to accompanying documentation.

Warning - risk of electric shock.

Warning - hot surfaces.

Protective conducter terminal.

The units used throughout this manual conform to the SI international system of units of measurement. Also throughout this manual, wherever flow rates are specified, the abbreviation 'sccm' is used to mean 'standard cm3 min-1: this is a flow of 1 cm3 min-1 at an ambient temperature of 0 °C and a pressure of 1013 mbar (1.013 x 105 Pa).

B753-03-880 Issue F

Introduction

1.2 Gener al description

The EXT255H, EXT255Hi and EXT255HVi pumps are compound vacuum pumps that combine a turbomolecular pump and a drag pump on a single shaft. Refer to Figure 1 and 2, which show the internal structures of the EXT255H and EXT255HVi pumps.

The turbomolecular pump is made from a multi-stage axial-flow turbine which is optimised for operation in molecular flow conditions. The drag pump is made from pumping channels formed by helical grooves. The drag pump is designed for operation at higher pressures than conventional turbomolecular pumps.

The light alloy rotor (13) is machined from one piece to form the angled blades of the turbomolecular pump. The rotor blades rotate between angled stator blades (12) which are supported by spacer rings (11). The rotor and stator blades have an open structure at the pump inlet, and a more closed structure at the outlet. This configuration gives an optimum combination of pumping sp eed and compression when pumping gases of both high and low molecular weight. For the blades to be effective, their speed must be close to the thermal velocity of the gas. The rotor therefore rotates at up to 60000 r min

Gas from the inlet is compressed through each of the bladed stages of the turbomolecular pump and transferred to the drag pump. In the drag pump stages, the gas is further compres sed as it is pump ed around the cha nne ls formed by the helical grooves.

The rotating assembly is supported at the inlet end by a frictionless magnetic bearing (3) and by a precis ion ceramic ball bearing (8) at the outlet end. The ball bearing is lubricated from an oil reservoir and wick mechanism (9).

-1

All of the pumps are supplied with an inlet-screen (2) fitted in the bore of the inlet-flange. The EXT2 55Hi pumps are also supplied with an inlet-strainer which fits in the interstage-port. The inlet-screen and inlet-s trainer p rotect the pump against damage which would be caused by debris which enters the pump. The inlet-screen also protects you from the sharp blades in the pump.

All of the pumps have a vent-port you can use to vent the pump and your vacuum system to atmospheric pressure. The vent-port introduces vent gas part way up the pump rotor; this ensures maximum cleanliness. The pump is supplied with a manual vent-valve fitted to the vent-port. As described in Section 3.4, you can replace the manual vent-valve with a TAV5 or TAV6 solenoid-operated vent-valve (available as an accessory: see Section 7).

All of the pumps have a purge-port (Figure 4 or 5, item 3) in the motor and bearing housing chamber. In order to protect the bearing lubricant from the effects of high oxygen concentrations, you can introduce an inert purge gas through the purge-port. You can fit an optional vent-port adaptor and purge restrictor to the purge-port to control the flow rate of the purge gas and to filter the gas supply (see Section 7).

The EXT255Hi pump has an interstage-por t, between the turbomolecular and drag pump. You can us e the interstageport to pump a separate chamber of your vacuum system or to back another turbomolecular pump. If the pump operates with an outlet pressure of less than 5 mbar (500 Pa) and an interstage inlet flow of less than 70 sccm (1.17 mbar l s interstage operating conditions.

The EXT255HVi pump also has an interstage-port (14). The interstage-port is located in the turbomo lecular p umping region of the pump and, together with the higher conductance provided by the larger size interstage-port, enables higher interstage pumping speeds than the EXT255Hi.

Electrical connection between the EXT and the EXC Controller is by a 19-way connector and a pump-to-controller cable. The cable is a separate item and is available in a choice of lengths (see Section 7 for details). If you use an EXC100L controller it is not necessary to buy a separate cable.

-1

, 117 Pa l s-1), the vacuum performance at the turbomolecular pump-inlet is independent of the

The pump may be cooled using air-cooled or water-cooled optional accessories. Refer to Section 3 for guidance on applications and cooling requirements. Pumps with a Conflat flange are supplied with a water-cooler.

All EXT pumps have thermal sensors to monitor the motor and pump-body temperature.

Edwards and the Edwards logo are trademarks of Edwards Limited.

B753-03-880 Issue F

1.3 Vent options and vent control

To maintain the cleanliness of your vacuum system, we recommend that, whenever you switch the pump off, you vent the pump (or vacuum system) when the speed of the EXT pump is between full rotational speed and 50% of full rotational speed. At and above 50% of full rotational speed, the rotor spins fa st enough to suppress an y backstreaming of hydrocarbon oil from your bac king pump.

However, if you vent the pump w hen it is at full rotational speed and the rate of pressure ri se is too high, the p ump life may be reduced. We therefore recommend that you either limit the vent rate (see Section 2.3), or only open the vent-valve after the EXT pump speed has fallen to 50% of full rotational speed.

The rate of pressure rise cannot be controlled by the manual vent-valve, so if you use the manual vent-valve, you must only open the vent-valve after the EXT pump speed has fallen to 50% of f u ll rotational speed.

If you use a TAV5 vent-valve, but you cannot limit the rate of pressure rise, you must only open the vent-valve after the speed of the EXT pump has fallen to 50% of full rotational speed. If you use the EXC Controller to control your TAV5 vent-valve, configure the EXC Controller to select this option: refer to Section 3.4 for more information. The EXC Controller is factory set to vent when the EXT pump is at 50% of full rotational speed after you select Stop.

Introduction

B753-03-880 Issue F

1. Inlet-flange

2. Inlet-screen

3. Magnetic bearing

4. Safety bearing

5. Envelope

6. Shaft

7. DC motor

8. Ball bearing

9. Oil reservoir

10.Drag stage

11.Spacer ring

12.Stator

13.Rotor

Introduction

Figure 1 - Cross-section view of EXT255H pump

Edwards and the Edwards logo are trademarks of Edwards Limited.

Figure 2 - Cross-section view of EXT255HVi pump

1. Inlet-flange

2. Inlet-screen

3. Magnetic bearing

4. Safety bearing

5. Envelope

6. Shaft

7. DC motor

8. Ball bearing

9. Oil reservoir

10.Drag stage

11.Spacer ring

12.Stator

13.Rotor

14.Interstage-port

B753-03-880 Issue F

Introduction

B753-03-880 Issue F

This page has been intentionally left blank.

Edwards and the Edwards logo are trademarks of Edwards Limited.

B753-03-880 Issue F

CAUTION

WARNING

2Technical data

2.1 General

Performance See Table 1 Dimensions See Figure 4 and 5 Maximum inlet-flange temperature 100 °C Maximum magnetic field 3.5 mT Horizontal field >7mT Vertical field Installation category EN61010 part 1, Category 1 Pollution degree CAN/CSA, UL, EN61010 part 1 Altitude 2000 m Humidity 10 to 90% non condensing Electrical supply 80 V d.c. Equipment type Fixed equipment, for indoor use only

2.2 Pumping media

Technical data

Vent dangerous gases and gas mixtures safely. Do not expose people to these gases.

Do not use EXT pumps to pump explosive gas mixtures as the pumps are not suitable for this purpose.

On EXT255Hi and EXT255HVi pumps, gas pumped through the interstage-port will mix with gas pumped through the pump-inlet. Ensure that the gases will not react or combine to form dangerous gases and substances.

Do not use an EXT to pump gases containing more than 20% oxygen unless the pump is gas purged. If you do, the lubricant will polymerise and the pump will fail prematurely.

Note: Note that concentrations of gases may be modified by the compression of the pump.

2.2.1 Pumps without gas purge

The pumps are designed to pump the following residual gases normally used in high-vacuum systems:

z Air z Carbon monoxide z Neon z Ethane z Methane z Nitrogen z Krypton z Argon z Propane z Carbon dioxide z Helium z Hydrogen z Butane

B753-03-880 Issue F

Technical data

You can use the pumps to pump oxygen and water vapour, subject to the following conditions:

z Oxygen The oxygen concentration must be less than 20% by volume. z Water vapour You must ensure that vapour does not condense inside the pump; refer to Section 3.7.3.

If you wish to pump a gas not in the list above, co ntact your supplier for advice. If you do not contact your supplier, you may invalidate the warranty on the pump. The pumps are not suitable for pumping aggressive or corrosive gases.

2.2.2 Pumps with gas purge

When purged with an inert gas, the pumps can be used to pump oxygen in concentrations above 20% by volume.

2.3 Vent gas specification and vent control data

Although the pump may be vented to atmospheric air, high relative humidity of the air may greatly increase the subsequent pump-down time. To reduce pump-down times you should vent the pump with dry, clean gases.

Vent gas Dry air, nitrogen, argon or other inert gases Maximum dew point at atmospheric pressure - 22 °C Maximum size of particulates 1 Maximum concentration of oil 0.1 parts per million Time for rotational speed to reach 50% >15 sec Rate of pressure rise see Figure 3

µm

2.4 Purge gas specification

Purge gas Dry nitrogen, argon or other inert gases Maximum dew point at atmospheric pressure -22 °C Maximum size of particulates 1 Maximum concentration of oil 0.1 parts per million Allowable purge gas flow (when required) 20 to 100 sccm (0.33 to 1.67 mbar l s Recommended purge gas flow 25 sccm (0.42 mbar l s Maximum allowable purge gas supply pressure 2 bar (gauge) ; 29 psig, 3 x 10

µm

-1

, 42 Pa l s-1)

-1

, 33 to 167 Pa l s-1)

Edwards and the Edwards logo are trademarks of Edwards Limited.

+ 30 hidden pages

Edwards EXT Series, EXT255Hi, EXT255H, EXT255HVi Instruction Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Contents

Illustrations

Tables

Associated publications

1Introduction

1.1 Scope and definitions

1.2 Gener al description

1.3 Vent options and vent control

2Technical data

2.1 General

2.2 Pumping media

2.2.1 Pumps without gas purge

2.2.2 Pumps with gas purge

2.3 Vent gas specification and vent control data

2.4 Purge gas specification