Edwards 18B4B User manual

B06510880
Issue D
Original Instructions
Instruction Manual
18B4B Vapour Booster Pumps

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Contents
B06510880 Issue D
Contents
Section Page
1 Introduction ....................................................................................... 1
1.1 Scope and definitions ................................................................................................... 1
1.2 Description ................................................................................................................ 1
1.3 Construction .............................................................................................................. 2
1.4 Principle of operation ................................................................................................... 2
1.5 Over-temperature protection .......................................................................................... 3
1.5.1 Cooling-fail thermal snap-switches ................................................................................... 3
1.5.2 Boiler-protection thermal snap-switch ............................................................................... 3
1.6 Low fluid level protection (optional) ................................................................................. 3
1.7 Temperature indication (optional) .................................................................................... 3
1.8 Operation with high ambient humidity ............................................................................... 3
2 Technical data .................................................................................... 7
2.1 Operating and storage conditions ..................................................................................... 7
2.2 Performance .............................................................................................................. 7
2.3 Mechanical data .......................................................................................................... 8
2.4 Pump fluid data .......................................................................................................... 8
2.5 Cooling-water data ...................................................................................................... 8
2.6 Electrical data ............................................................................................................ 9
2.7 Construction materials .................................................................................................. 9
2.8 Pump Item Numbers ....................................................................................................10
3 Installation ....................................................................................... 15
3.1 Safety .....................................................................................................................15
3.2 Unpack and inspect .....................................................................................................15
3.3 Locate the pump ........................................................................................................16
3.3.1 General requirements ..................................................................................................16
3.3.2 Installation on a vacuum system .....................................................................................16
3.3.3 Free-standing installation .............................................................................................17
3.4 Vacuum connections ...................................................................................................17
3.4.1 System design ...........................................................................................................17
3.4.2 Connect the pump inlet ................................................................................................18
3.4.3 Connect the pump outlet ..............................................................................................18
3.5 Cooling-water connections ............................................................................................19
3.6 Pump fluid drain connection (optional) .............................................................................20
3.7 Connect the electrical supply .........................................................................................20
3.7.1 Electrical safety .........................................................................................................20
3.7.2 Connect the supply to the pump .....................................................................................21
3.8 Connect the thermal snap-switches .................................................................................25
3.8.1 Connect the cooling-fail thermal snap-switches ...................................................................25
3.8.2 Connect the boiler protection thermal snap-switch ..............................................................25
3.9 Connect the optional Pt100 temperature probe (if fitted) .......................................................25
3.10 Leak test the system ...................................................................................................26
3.11 Fill the pump with fluid ................................................................................................26
3.11.1 Safety of vapour pump fluids .........................................................................................26
3.11.2 Recommended pump fluids ...........................................................................................27
3.12 Filling procedure ........................................................................................................27
3.12.1 Introduction .............................................................................................................27
3.12.2 General filling procedure ..............................................................................................27
3.12.3 Filling procedure for adjustment of the fluid low level switch ..................................................29
3.13 Connect the optional fluid low level switch (if fitted) ...........................................................29
2020-VIN-GCN-0044

B06510880 Issue D
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Contents
4 Operation ........................................................................................ 31
4.1 Introduction .............................................................................................................31
4.2 Check the insulation resistance of the heaters ....................................................................31
4.3 Start-up ..................................................................................................................32
4.4 Rough pumping ..........................................................................................................32
4.5 Adjust the boiler protection thermal snap-switch (if necessary) ...............................................33
4.6 Re-admission of air to your vacuum system ........................................................................34
4.7 Re-evacuation of your vacuum system ..............................................................................34
4.8 Shut-down ................................................................................................................34
5 Maintenance ..................................................................................... 37
5.1 Safety .....................................................................................................................37
5.2 Tools and equipment required ........................................................................................37
5.3 Maintenance plan .......................................................................................................38
5.4 Check the pump fluid-level ...........................................................................................38
5.5 Inspect the pump fluid (and drain if necessary) ...................................................................38
5.6 Clean and inspect the pump ..........................................................................................39
5.6.1 Introduction .............................................................................................................39
5.6.2 Dismantle the pump ....................................................................................................39
5.6.3 Clean the main pump components ...................................................................................40
5.6.4 Clean the interior components ....................................................................................... 41
5.6.5 Clean the boiler and fluid return pipes .............................................................................41
5.6.6 Reassemble the pump ..................................................................................................41
5.6.7 Prepare the pump for operation .....................................................................................42
5.7 Clean the radiation shield .............................................................................................43
5.8 Replace a pump heater ................................................................................................43
5.8.1 Prepare the pump ......................................................................................................43
5.8.2 Identify and remove the defective heater ..........................................................................44
5.8.3 Assemble and fit the new heater .....................................................................................46
5.8.4 Reassemble the pump ..................................................................................................46
5.9 Check the heater clamp plate and retaining nuts .................................................................47
5.10 Clean the cooling-coil ..................................................................................................47
5.11 Fault finding .............................................................................................................47
6 Storage and disposal ........................................................................... 49
6.1 Storage ...................................................................................................................49
6.2 Disposal ...................................................................................................................49
7 Service, spares and accessories .............................................................. 51
7.1 Introduction .............................................................................................................51
7.2 Service ....................................................................................................................51
7.3 Spares .....................................................................................................................51
7.4 Accessories ...............................................................................................................51
Index .............................................................................................. 53
For return of equipment, complete the HS Forms at the end of this manual.

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Contents
B06510880 Issue D
Illustrations
Figure Page
1 Part-sectional view of the 18B4B pump .............................................................................. 5
2 Typical performance curves ...........................................................................................11
3 Dimensions (mm) .......................................................................................................13
4 Heater wiring connections ............................................................................................21
5 Terminal block ..........................................................................................................22
6 Terminal block links for Star connections ..........................................................................22
7 Star connection wiring diagram ......................................................................................23
8 Terminal block links for Delta connections .........................................................................23
9 Delta connection wiring diagram .....................................................................................23
10 Recommended control circuit ........................................................................................24
11 Adjust the boiler protection thermal snap-switch .................................................................33
12 Typical pumping system ............................................................................................... 35
13 Replace a heater ........................................................................................................45
Tables
Table Page
1 Operating and storage conditions ..................................................................................... 7
2 Performance data ........................................................................................................ 7
3 Mechanical data .......................................................................................................... 8
4 Pump fluid data .......................................................................................................... 8
5 Cooling-water data ...................................................................................................... 8
6 Electrical data ............................................................................................................ 9
7 Construction materials .................................................................................................. 9
8 Pump Item Numbers ....................................................................................................10
9 Checklist of items .......................................................................................................15
10 Vapour pump fluid thermal breakdown .............................................................................28
11 Maintenance plan .......................................................................................................38
12 Fault finding .............................................................................................................47
13 18B4B accessories .......................................................................................................51
14 18B4B pump spares .....................................................................................................52

B06510880 Issue D
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Contents
Supplementary publications
Publication title Publication number
iTEMP PCP TMT 181 Temperature head transmitter KA 141R/09/a3/07.02 51004624
liquiphant S FTL70, FTL71 Level Limit Switch KA 172F/00/a6/04.03 52009621
liquiphant M FTL 51 High Pressure Sliding Sleeve KA 153F/00/a6/12.99 52004587
Note: The above manufacturer’s instructions will only be provided with pumps supplied fitted with the
corresponding option(s).
Associated publications
Publication title Publication number
Application Note: Operation of diffusion pumps in environments
with high ambient humidity P400-50-000
Trademark credits
Fomblin® is a registered trademark of Solvey Solexis
Apiezon® is a registered trademark of M & I Materials, UK

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Introduction
B06510880 Issue D
1 Introduction
1.1 Scope and definitions
This manual provides installation, operation and maintenance instructions for the Edwards 18B4B Vapour Booster
Pumps. You must use the pumps as specified in this manual.
Read this manual before you install and operate your pump. Important safety information is highlighted as WARNING
and CAUTION instructions; you must obey these instructions. The use of WARNINGS and CAUTIONS is defined below.
CAUTION
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 IEC1010, the following warning symbols may appear on the pump or its
accessories:
The units used throughout this manual conform to the SI international system of units of measurement.
The pump identification and rating plate (Figure 3, item 12) provides specific details about the pump, including:
pump type; part number and serial number; name and address of manufacturer; and so on.
1.2 Description
The 18B4B pumps are high performance vapour booster pumps, and have pumping speeds of up to 4000 l s-1.
The pumps are rugged and reliable and have high performance even with relatively high backing pressures.
Three versions of 18B4B pumps are available, with different inlet and outlet flanges: refer to Section 2.8.
WARNING
Warnings are given where failure to observe the instruction could result in injury or death to
people.
Warning - refer to accompanying documentation.
Warning - risk of electric shock.
Warning - hot surfaces.

B06510880 Issue D
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Introduction
1.3 Construction
Refer to Figure 1 which shows a part-sectional view of the 18B4B pump. The pump has:
A vertical top cone assembly (45) which incorporates the three diffusion pump stages (42, 6 and 5).
A horizontal side cone assembly (14).
A boiler (33), which forms part of the base of the pump.
A ‘T’ piece (38), which connects the top cone (45), the side cone (14) and the boiler (33).
A vertical backing condenser (17), which incorporates a baffle assembly (18).
The diffusion pumping jet stages have top (5), second stage (6) and lower (42) vapour tubes, each of which has a jet
cap (47, 44, 43). The top jet cap is covered by a guard ring (2), which minimises the backstreaming of pump fluid.
The lower vapour tube is bolted to the ejector stage ‘T’ piece (38), and the ‘T’ piece is bolted to the boiler assembly
(33), through flanges to allow easy access for cleaning.
The ejector nozzle (8) is housed in the ‘T’ piece (38), which is bolted to the side cone (14) into which the ejector
discharges. The side cone ends in a vertical backing condenser (17).
The pump fluid is heated and vaporised by electric heaters (27). There are three heaters in the pump, rated the same
for all voltage variants. The boiler (33) has a dipstick/fluid filler connection (21) and a fluid drain connection (29).
The electrical supply cables from the heaters are connected into a terminal box (31) on the base of the pump, for
ease of connection to your electrical supply.
The pump boiler assembly (33) has a cleaning port cover (10). You can remove this cover and use the cleaning port
to remove any residue build up from the inside of the boiler. You should regularly clean the boiler, to maintain the
pump performance at its optimum level. A radiation shield (22) underneath the heaters reflects heat from the
underside of the heaters (27) to the boiler, and so increases the efficiency of the pump.
The pump is cooled by water, which flows through copper cooling-coils (13, 19, 41) wound around the top cone, the
side cone and the backing condenser. The cooling couplings (36, 40) connect these coils together, to form a single
cooling circuit around the pump.
The pump can be supplied with one or both of the following optional items:
A fluid low level switch (12): see Section 1.6.
A Pt100 temperature probe (30): see Section 1.7.
1.4 Principle of operation
Refer to Figure 1. Pump fluid is heated in the boiler (33) to produce a vapour, which passes up through the interior
of the diffusion pumping stages (42, 6, 5) and emerges from the gaps in the jet caps (43, 44, 47) as high velocity
vapour streams. The vapour streams condense on the cooled walls of the top cone (45) and the side (ejector)
cone (11), then drain into the boiler (33) for recirculation.
A portion of system gas which arrives at the pump inlet (1), is trapped in the vapour stream from the first stage jet
cap (47) The gases are compressed and transferred to the next stage. The gases then pass through the ejector
nozzle (8) and into the backing condenser (17) where they are removed (through the outlet, 16) by your
backing pump.
The cooled surface of the guard ring (2) above the top jet cap (47) traps and condenses pump fluid vapour and
minimises any backstreaming of pump fluid vapour into your vacuum system.

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Introduction
B06510880 Issue D
1.5 Over-temperature protection
1.5.1 Cooling-fail thermal snap-switches
Refer to Figure 1. The pump has two cooling-fail thermal snap-switches (7, 9) on the cooling-coils. These
snap-switches protect the pump against damage due to failure of the cooling-water supply.
Both snap-switches have normally closed contacts that will open if the temperature of the cooling coils increases
above 46 °C. The snap-switches will reset automatically when the pump cools down.
You must configure the snap-switches to switch off the electrical supply to the pump heaters when the snap-switch
contacts open. You must also interlock the snap-switches so that the pump cannot automatically restart after the
snap-switch contacts have opened and the pump has then cooled again, until the problem has been rectified.
1.5.2 Boiler-protection thermal snap-switch
The pump has a boiler protection thermal snap-switch (Figure 3, item 20) fitted to the wall of the boiler.
The snap-switch protects the pump against damage due to a low level of pump fluid, which causes the boiler
temperature to rise.
As supplied, the snap-switch contacts will open when the boiler wall temperature reaches 250 °C.
You must configure the snap-switch to switch off the electrical supply to the pump heaters when the snap-switch
contacts open. You must also interlock the snap-switch so that the pump cannot automatically restart after the
snap-switch contacts have opened and the pump has then cooled again, until the problem has been rectified.
1.6 Low fluid level protection (optional)
Your pump may be supplied with an optional fluid low level switch (Figure 1, item 12).
If fitted, this level switch will provide a warning that the fluid level in the pump boiler is low, and that more fluid
needs to be added.
As supplied, the level switch is preset to operate when the fluid level in the boiler has fallen to 6 litres.
1.7 Temperature indication (optional)
Your pump may be supplied with an optional Pt100 temperature probe (Figure 1, item 30), fitted to the fluid drain
connection.
If fitted, this probe will provide an indication of the temperature of the pump fluid.
1.8 Operation with high ambient humidity
When the pump is switched off, the heaters in the pump will absorb moisture: this will cause a decrease in the
insulation resistance of the heaters. If you operate the pump in an environment with high ambient humidity, this may
cause the heaters to fail. The rate of moisture absorption (and therefore the time taken for the insulation resistance
of the heaters to fall below the recommended value) depends on the ambient humidity and temperature and the
length of time that the pump is switched off.
In addition to the recommendations made in later sections of this manual, you can overcome the effect of high
ambient humidity if you:
Configure the electrical installation of the pump for ‘soft-start’ operation, when the pump is operated with
typically 20 to 25% of the nominal supply voltage.
Install an anti-moisture heater under the base of the pump. Switch on this heater when you switch off
the pump.

B06510880 Issue D
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Introduction
Detailed information about these recommendations is outside the scope of this manual. If you need more information
about the operation of the pump with high ambient humidity, request a copy of our Application Note P40050000 from
your supplier or Edwards.
Figure 1 - Part sectional view of the 18B4B pump: key
1. Inlet
2. Guard ring
3. Inlet ‘O’ ring
4. Cooling-water inlet
5. Top vapour tube
6. Second stage vapour tube
7. Cooling-fail thermal snap-switch
8. Ejector nozzle
9. Cooling-fail thermal snap-switch
10. Cleaning port cover and gasket
11. Cleaning port access lid
12. Fluid low level switch (optional)
13. Cooling-coil
14. Side cone assembly
15. Cooling-water outlet
16. Outlet (backing connection)
17. Backing condenser
18. Baffle
19. Cooling-coil
20. Condenser fluid return pipe
21. Dipstick
22. Heater radiation shield
23. Mounting feet
24. Clamp plate
25. Heater retaining nut
26. Heater cover
27. Heater
28. Earth (ground) stud
29. Fluid drain plug
30. Pt100 temperature probe (optional)
31. Terminal box
32. Boiler base
33. Boiler
34. Jet stack fluid return pipe
35. Tie-rod
36. Cooling coupling
37. ‘T’ piece ‘O’ ring
38. ‘T’ piece
39. Jet gasket
40. Cooling coupling
41. Cooling-coil
42. Lower vapour tube
43. Lower jet cap
44. Second stage jet cap
45. Top cone assembly
46. Locating pin
47. Top jet cap
48. Setting dimension: 1.6 mm 1
1This is the setting dimension for
Edwards 201 fluid. This dimension may
differ if you use a different fluid: refer to
Section 5.6.6.

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Introduction
B06510880 Issue D
Figure 1 - Part-sectional view of the 18B4B pump

B06510880 Issue D
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Technical data
B06510880 Issue D
2 Technical data
2.1 Operating and storage conditions
2.2 Performance
Note: The performance data in Table 2 and in Figure 2 is for use of the pump with Edwards 201 fluid.
The pumping speeds and throughput specified below and shown in Figure 2 were calculated from
measurements made with partial pressure gauges. If total pressure gauges are used, the calculated values
for pumping speeds are approximately 10% lower. This is because partial pressure gauges do not measure
the pressure added to the system by condensable gases.
We do not give absolute values for the ultimate pressure of the pump. The ultimate pressure depends on
the fluid used in the pump, the leak tightness of the system, outgassing from surfaces, and the use of
cold traps.
Table 1 - Operating and storage conditions
Maximum ambient operating temperature 40 °C
Typical surface temperature during operation
Jet stage cone 30 °C
Boiler 200 °C
Maximum surface temperature during operation
Jet stage cone 55 °C
Under covers/below the pump 250 °C
Minimum backing pump displacement 190 m3 h-1
Recommended Edwards backing pump GV260M, E2M275
Recommended Holding pump Minimum 10% of backing pump
Table 2 - Performance data
Performance curves See Figure 2
Maximum system pressure (absolute) 1.3 bar absolute, 1.3 x 105 Pa
Critical backing pressure 2 to 2.6 mbar, 2 to 2.6 x 102 Pa
Pumping speed (ISO)
Air 4000 l s-1
Hydrogen 6000 l s-1
Maximum throughput (air) 100 mbar l s-1, 1 x 104 Pa l s-1
Backstreaming rate at ultimate vacuum 0.7 mg cm-2 min-1
Fluid loss at 1 x 10-1 mbar, 10 Pa 10 g h-1
Warm-up time to maximum throughput 60 min
Cool-down time (to approximately 100 °C) 120 min

B06510880 Issue D
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Technical data
2.3 Mechanical data
2.4 Pump fluid data
Note: A Edwards Material Safety Data Sheet for the fluid specified below is available on request.
2.5 Cooling-water data
Table 3 - Mechanical data
Dimensions See Figure 3
Mass
Complete pump (without fluid) 165 kg
Complete pump (with full fluid charge) 175 kg
Jet stage cone 40 kg
Side cone assembly 20 kg
Cleaning port cover * 8 kg
Heater assembly and terminal box * 10 kg
Boiler assembly (jncluding * items above) 105 kg
Maximum stability angle 10°
Inlet flange EHVI, ANSI12 or ISO320: see Figure 3
Outlet flange 2 inch union, ANSI14 or ISO160: see Figure 3
Cooling-water connections 1/2 inch BSP female (with 1/2 inch NPT male adaptors)
Table 4 - Pump fluid data
Recommended fluid type Edwards 201 or AP201
Fluid charge
Nominal 10 l
Minimum 6 l
Fluid data
Flash point 196 °C
Auto-ignition point 320 °C for Edwards201
305 °C for AP201
Molecular weight 310
Table 5 - Cooling-water data
Maximum allowed water outlet temperature 35 °C
Minimum cooling-water flow rate (at 25 °C) 375 l h-1
Pressure differential across supply and return
(with minimum recommended flow rate) 1.3 bar gauge, 1.3 x 105 Pa

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Technical data
B06510880 Issue D
2.6 Electrical data
2.7 Construction materials
Table 6 - Electrical data
Heater rating 2 kW
Nominal heater power (3 heaters) 6 kW
Electrical supply
Nominal 200 V supply 200 - 210 V, 50/60 Hz, three-phase
Nominal 220 V supply 220 - 230 V, 50/60 Hz, three-phase
Nominal 240 V supply 240 - 250 V, 50/60 Hz, three-phase
Nominal 380 V supply 380 - 400 V, 50/60 Hz, three-phase
Nominal 440 V supply 415 - 440 V, 50/60 Hz, three-phase
Nominal 480 V supply 460 - 480 V, 50/60 Hz, three-phase
Over-current protection settings (on full heat)
200 V, 50/60 Hz 20 A
220 V, 50/60 Hz 18 A
240 V, 50/60 Hz 16 A
380 V, 50/60 Hz 11 A
440 V, 50/60 Hz 10 A
480 V, 50/60 Hz 9 A
Cooling-fail thermal snap-switch rating 6.3 A at 250 V a.c.
Boiler protection thermal snap-switch rating 5 A at 240 V a.c.
Maximum interlock control voltage 277 Vac
Recommended control voltage 24 Vac
Pt100 temperature probe (optional)
Output (proportional to measurement range) 4 to 20 mA
Measurement range 0 to 300 °C
Power supply voltage 8 to 35 V d.c.
Fluid low level switch (optional)
Power supply voltage 19 to 253 V a.c. or 19 to 55 V d.c.
Relay contacts maximum voltage 253 V a.c., 30 V d.c.
Relay contacts maximum current 6 A
Table 7 - Construction materials
Pump body Nickel plated/painted mild steel
Covers Anodised aluminium
Water cooling coils High conductivity copper
Inlet and backing ‘O’ rings Fluoroelastomer
Internal pump ‘O’ rings Fluoroelastomer
Jet stack gasket Aramid fibre in nitrile rubber binder
Boiler port gasket Carbon fibre in nitrile rubber binder

B06510880 Issue D
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Technical data
2.8 Pump Item Numbers
Table 8 - Pump Item Numbers
Pump voltage and options Inlet
EHVI ANSI ISO
18B4B pump
200 V B06510200 B06520200 B06530200
220 V B06510220 B06520220 B06530220
240 V B06510240 B06520240 B06530240
380 V B06510380 B06520380 B06530380
440 V B06510440 B06520440 B06530440
480 V B06510480 B06520480 B06530480
18B4B pump, with Pt100 temperature probe
200 V B06511200 B06521200 B06531200
220 V B06511220 B06521220 B06531220
240 V B06511240 B06521240 B06531240
380 V B06511380 B06521380 B06531380
440 V B06511440 B06521440 B06531440
480 V B06511480 B06521480 B06531480
18B4B pump, with fluid low level switch
200 V B06512200 B06522200 B06532200
220 V B06512220 B06522220 B06532220
240 V B06512240 B06522240 B06532240
380 V B06512380 B06522380 B06532380
440 V B06512440 B06522440 B06532440
480 V B06512480 B06522480 B06532480
18B4B pump, with Pt100 and fluid low level switch
200 V B06513200 B06523200 B06533200
220 V B06513220 B06523220 B06533220
240 V B06513240 B06523240 B06533240
380 V B06513380 B06523380 B06533380
440 V B06513440 B06523440 B06533440
480 V B06513480 B06523480 B06533480

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Technical data
B06510880 Issue D
Figure 2 - Typical performance curves
1. Pumping speed (l s-1) against inlet pressure (mbar/Pa) for nitrogen
2. Throughput (mbar l s-1) against inlet pressure (mbar/Pa) for nitrogen

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Technical data
Figure 3 - Dimensions (mm): key
1. Inlet
2. Cooling-water inlet
3. Outlet
4. Cooling-water outlet
5. Cooling-fail thermal snap-switches
6. Clearance required to remove heaters
7. Fluid low level switch (optional)
8. Electrical box
9. Earth (ground) stud
10. Pt100 temperature probe (optional)
11. Fluid drain connection
12. Identification and rating plate
13. Hot surfaces: temperatures below this line can reach 250 °C
14. Fixing holes (3 off): Ø17.5 on 549 PCD
15. ISO inlet
16. EHVI inlet
17. ANSI inlet
18. ANSI outlet (8 holes Ø19.2 on 190.5 PCD)
19. ISO outlet (8 holes Ø11.2 on 200 PCD)
20. EHVI outlet (2 inch union nut and tailpiece, counter-bored Ø54.1-54.18 x
19.4, 20.2 deep)
21. Boiler protection thermal snap-switch
22. Fixing holes:
12 holes Ø14 on 395 PCD (ISO inlet)
12 holes Ø25.4 on 431.8 PCD (ANSI inlet)
8 holes Ø11 on 387.4 PCD (EHVI inlet)
ØA ØB C
ANSI 482.6 228.6 807
ISO 425 225 807
EHVI 406 178 810

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Technical data
B06510880 Issue D
Figure 3 - Dimensions (mm)

B06510880 Issue D
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