www . mksinst . c o mValve Solutions

Two-Stage Valves
Soft start vacuum valves

Features and Benefits• Provides soft pumpdown and isolation of your vacuumsystem• Reduces particulate contamination during early turbulent
pumpdown• Adjustable conductance for variable pumpdown speed• Eliminates the need for small bypass lines that clogeasily• Bellows-sealed poppet valves• Bellows are formed for less particle trapping and alonger cycle life• Angle or inline option• Available in five port diameters ranging from 1 - 4 inches• Choice of KF flanges, CF flanges, or weld stubs, as wellas ISO-Universal flanges for larger port sizes

The body is made of high grade, corrosion resistant,
304 stainless steel using clean, tungsten inert gas (TIG)
welding for significantly fewer entrapment areas, resulting
in less contaminant build-up.
A formed 321 stainless steel bellows, not edge-welded,
prevents outgassing, virtual leaks, and particle entrapment
between bellows convolutions and extends the valve’s
cycle life. The bellows stroke length is optimized to ensure
a longer cycle life while maintaining a high conductance.
Elastomer seal choices include Viton® and Chemraz®,
which has a higher chemical resistance. Vacuum exposedparts are clean and free of lubricants.
Options include air solenoids for electropneumatic control
and a limit switch for the main valve for remote indicationof valve position (open or closed). If a heated Two-Stage
Valve is required, please refer to our Jalapeño Valve
brochure.

Applications

Conductance

To achieve a soft pumpdown and isolate your vacuum
system, MKS recommends its Two-Stage Valve. Itintegrates a small bypass valve into an isolation valve,significantly simplifying system setup and reducing costs.

107

Conductance (Liters/Second)

NW 100The Two-Stage Valve is best suited for high vacuum
applications, specifically semiconductor or opticalprocessing for which a cleaner environment is necessary.
With the integrated slow pumpdown feature, turbulent
flow is diminished preventing contamination buildup anddamage to your product.

106

NW 80

105

NW 40

NW 50

NW 25

104
103
102
101

Description

10-6

Traditionally, the method to soft start a vacuum system
had been to run a secondary bypass line with a small
orifice valve around the main vacuum isolation valve. The
use of bypass lines in semiconductor nitride and etch
processes requires special engineered designs that are
hardware intensive. These lines also clog easily and resultin higher costs.
MKS has designed the Two-Stage Valve specifically toaccommodate space constraints and soft start the system
in two steps. In the first stage, the bypass valve allows
slow pumping from atmospheric pressure to a userspecified vacuum pressure. In the second stage, the mainvalve opens, allowing use of full pumping speed.

10-510-410-3

10-2
10-1
Pressure (Torr )1.0 (25)
1.5 (40)
2.0 (50)
3.0 (80)
4.0 (100)

101

102

Specifications
Vacuum Range

Atmosphere to 1.0 x 10-9 Torr

Suggested Nominal Pressure Supply

65 psig

Helium Leak Rate

1.0 x 10-9 std cc/sec

Maximum Bakeout Temperature

150°C - Body

Limit Switch Rating
Single Pole, Single Throw

5A - 250 VAC
5A - 30 VDCSpecifications - Bypass
Bypass Orifice Sizes Available

The Two-Stage Valve features a removable small orifice
Pneumatic Cylinder Displacement Volume
within the bypass valve to vary slow pump speeds. The
standard bypass orifice diameter is 0.225 inches. See
Approximate Pneumatic Closing Time
specifications for other available sizes. A normally closed,
Blow-By Pressure
pneumatically actuated valve at both stages, the TwoMaximum Internal Spring Closing Pressure
Stage Valve is offered with an optional thumbscrew or
micrometer head for the bypass valve. 			
This allows for flow adjustment by limiting
Specifications - Main
the stroke.
Port Sizein. (NW)100

Weight lb (kg)
Angle

InlineCylinderVolumein3 (cm3)

3.0 (1.4)
6.0 (2.7)
13.8 (6.3)
20.4 (9.3)
26.3 (11.9)

3.0 (1.4)
6.6 (3.0)
17.5 (8.0)
28.5 (13.0)
38.5 (17.5)

3.6 (59)
4.8 (79)
13.3 (218)27.6 (453)27.6 (453)0.225'', 0.063'', 0.125'',0.187'' and custom
0.25 in3, (4.1 cm3)
100 msec
45 psia
40 psia

Actuation Time(msec)
Opening(closing)

Blow-By
Pressurepsia

Max. Internal
Spring Closing
Pressurepsia

500 (1,000)
1,000 (2,000)
1,000 (2,000)
2,000 (2,000)
2,000 (2,000)

60
50
45
3830

43
60
38
40
30

Ordering Information
NW 25 Angle Dimensionsin./(mm)KF

CFTubeA

2.47 (63)2.61 (66)2.47 (63)B

1.97 (50)2.02 (51)1.88 (48)

NW 25 In-Line Dimensions

Ain./(mm)

KF

CFTube4.97 (126)

5.62 (143)5.37 (136)

NW 25 Two-Stage Valve Ordering Information
Body Configuration

BypassActuator Type-X

Limit Switch

Seal Type

V2-XXX-XX

BypassOrifice Size
-XXX

X

Select 1

Select 1

Select 1

Select 1

V2-025-AK
KF 25 Angle

V2-025-IK
KF 25 Inline

V2-025-AT
1'' Tube Angle

V2-025-IT

X

Temperature
Configuration
XX

Pneumatic Solenoid
Voltage*-XXX

Select 1

Select 1

Select 1 or leave blank

225CL

V

NH

24A

0.225''

Normally
Closedw/ Limit
SwitchViton®

Regular

24 VAC 50/60 HzVNZ

24DChemraz®

24 VDC

Thumb
Screw

w/o Limit
SwitchM
Micometer
Head

1'' Tube Inline

V2-025-AC
CF 21/8'' Angle

V2-025-IC
CF 21/8'' Inline

Add the price of the options to the price of the body. Sample part number: V2-025-AK-225-CLVNH-120.
* Price includes one solenoid each for the bypass and main valve.

120120 VAC 50/60 Hz

208
208 VAC 50/60 Hz

240
220 VAC 50/60 HzNone

Main: 1/8'' NPT-F
Bypass: 10-32
UNF-F

NW 40 Angle Dimensions

in./(mm)

KF

CFTubeA

4.00 (102)4.03 (102)3.85 (98)B

3.00 (76)3.03 (76)3.85 (98)

NW 40 In-Line Dimensions

Ain./(mm)KF

CFTube12.00 (305)12.07 (307)11.70 (297)

NW 40 Two-Stage Valve Ordering Information
Body Configuration

BypassActuator Type-X

Limit Switch

Seal Type

V2-XXX-XX

BypassOrifice Size-XXX

X

Select 1

Select 1

Select 1

Select 1

V2-040-AK
KF 40 Angle

V2-040-IK
KF 40 Inline

V2-040-AT
11/2'' Tube Angle

V2-040-IT

X

Temperature
Configuration
XX

Pneumatic Solenoid
Voltage*-XXX

Select 1

Select 1

Select 1 or leave blank225CLVNH

24A

0.225''

Normally
Closedw/ Limit
SwitchViton®

Regular

24 VAC 50/60 HzVN

Z

24D

Chemraz®

24 VDC

Thumb
Screw

w/o Limit
SwitchM
MicometerHead

11/2'' Tube Inline

V2-040-AC
CF 23/4'' Angle

V2-040-IC
CF 23/4'' Inline

Add the price of the options to the price of the body. Sample part number: V2-040-AK-225-CLVNH-120.
* Price includes one solenoid each for the bypass and main valve.

120
120 VAC 50/60 Hz

208
208 VAC 50/60 Hz

240
220 VAC 50/60 Hz

None

Main: 1/8'' NPT-F
Bypass: 10-32
UNF-F

Ordering Information
NW 50 Angle Dimensions

in./(mm)

KF

CFTubeA

4.75 (121)

4.81 (122)

4.61 (117)B

3.50 (89)

3.55 (90)3.35 (85)

NW 50 In-Line Dimensions in./(mm)A

KF

CFTube12.00 (305)12.10 (307)11.70 (297)

NW 50 Two-Stage Valve Ordering Information
Body Configuration

BypassActuator Type-X

Limit Switch

Seal Type

V2-XXX-XX

BypassOrifice Size-XXXX

Select 1

Select 1

Select 1Select 1V2-050-AK
KF 50 Angle

V2-050-IK
KF 50 Inline

V2-050-AT
2'' Tube Angle

V2-050-IT
2'' Tube Inline

X

Temperature
Configuration
XX

Pneumatic Solenoid
Voltage*-XXX

Select 1Select 1Select 1 or leave blank

225

CL

V

NH

24A

0.225''

Normally
Closedw/ Limit
SwitchViton®

Regular

24 VAC 50/60 HzVNZ

24DChemraz®

24 VDC

Thumb
Screw

w/o Limit
SwitchM
Micometer
Head

V2-050-AC
CF 33/8'' Angle

V2-050-IC
CF 33/8'' Inline

Add the price of the options to the price of the body. Sample part number: V2-050-AK-225-CLVNH-120.
* Price includes one solenoid each for the bypass and main valve.

120
120 VAC 50/60 Hz

208
208 VAC 50/60 Hz

240
220 VAC 50/60 Hz

None

Main: 1/8'' NPT-F
Bypass: 10-32
UNF-F

NW 80 Angle Dimensions

in./(mm)

KF/MF

CF

Tube

A

5.50 (140)5.59 (142)5.25 (134)B

4.00 (102)4.09 (104)3.75 (95)

NW 80 In-Line Dimensions in./(mm)

A

KF/MF

CFTube18.00 (457)18.19 (462)17.49 (444)

NW 80 Two-Stage Valve Ordering Information
Body Configuration

BypassActuator Type-X

Limit SwitchSeal Type

V2-XXX-XX

BypassOrifice Size-XXXX

Select 1

Select 1

Select 1

Select 1

V2-080-AM
MF 80 Angle

V2-080-IM
MF 80 Inline

V2-080-AK
KF 80 Angle

V2-080-IK
KF 80 Inline

X

Temperature
Configuration
XX

Pneumatic Solenoid
Voltage*-XXX

Select 1

Select 1

Select 1 or leave blank

225CL

V

NH

24A

0.225''

Normally
Closedw/ Limit
SwitchViton®

Regular

24 VAC 50/60 HzVN

Z

24D

Chemraz®

24 VDC

Thumb
Screw

w/o Limit
SwitchM
MicometerHead120
120 VAC 50/60 Hz

208
208 VAC 50/60 Hz

V2-080-AT

240

3'' Tube Angle

220 VAC 50/60 Hz

V2-080-IT
3'' Tube Inline

V2-080-AC
CF 45/8'' Angle

V2-080-IC
CF 45/8 Inline

Add the price of the options to the price of the body. Sample part number: V2-080-AK-225-CLVNH-120.
* Price includes one solenoid each for the bypass and main valve.

None

Main: 1/8'' NPT-F
Bypass: 10-32
UNF-F

Ordering Information
NW 100 Angle Dimensions

in./(mm)

KF/MF

CFTubeA

6.50 (165)

6.65 (169)

6.25 (159)B

4.88 (124)

5.03 (128)4.63 (118)

NW 100 In-Line Dimensions

Ain./(mm)KF/MF

CFTube18.00 (457)18.30 (465)

17.49 (444)

NW 100 Two-Stage Valve Ordering Information
Body Configuration

BypassActuator Type-X

Limit Switch

Seal Type

V2-XXX-XX

BypassOrifice Size-XXXX

Select 1

Select 1

Select 1

Select 1

V2-100-AM
MF 100 Angle

V2-100-IM
MF 100 Inline

V2-100-AK
KF 100 Angle

V2-100-IK
KF 100 Inline

X

Temperature
Configuration
XX

Pneumatic Solenoid
Voltage*-XXX

Select 1

Select 1

Select 1 or leave blank

225

CL

VNH

24A

0.225''

Normally
Closedw/ Limit
SwitchViton®

Regular

24 VAC 50/60 HzVNZ24DChemraz®

24 VDC

Thumb
Screw

w/o Limit
SwitchM
MicometerHead120
120 VAC 50/60 Hz

208
208 VAC 50/60 Hz

V2-100-AT

240

4'' Tube Angle

220 VAC 50/60 Hz

V2-100-IT
4'' Tube Inline

V2-100-AC
6'' CF Angle

V2-100-IC
6'' CF Inline

Add the price of the options to the price of the body. Sample part number: V2-100-AK-225-CLVNH-120.
* Price includes one solenoid each for the bypass and main valve.

None

Main: 1/8'' NPT-F
Bypass: 10-32
UNF-F

Ordering Information
Spare Parts
Port Sizein (mm)Main Valve Internals,Viton SealsLimit Switch

Viton Seal Set *Chemraz Seal Set *Part Number

Part Number

Part Number

Part Number

100004918
100007131
100007132
100007133
100004917

100001520
100001520
100001683
100001684
100003663

100004915
100004913
100004911
100004909
100004907

100004916
100004914
100004912
100004910
100004908

1.0 (25)
1.5 (40)
2.0 (50)
3.0 (80)
4.0 (100)* In each set, the bonnet and nosepiece seals are of the material specified, and all other seals are of their original material.

Replacement Solenoid Valves
Voltage and Frequency

Watts

Part Number

24 VAC 50/60 Hz
24 VDC12 VDC
120 VAC 50/60 Hz
208 VAC 50/60 Hz
220 VAC 50/60 Hz

6.0
7.0
7.0
7.5
7.5
7.5

100008164
100008163
100008539
100008165
100008166
100008167

Bypass Valve Spare Parts,
Viton Seals
Internal Rebuild Kits

Conversion Kits **Part Number

Part Number

100004937
100004938
100004939

100004919
100004920
100004921

Actuator Type

Normally Closed
Thumb Screw
Micrometer** Conversion kits are for converting one bypass actuator type to another(i.e. thumbscrew to micrometer head).

Two-Stage Valves - 11/15© 2008 MKS Instruments, Inc.
All rights reserved.

MKS Instruments, Inc.
Global Headquarters

MKS Instruments, Inc.
Valve Solutions

2 Tech Drive, Suite 201
Andover, MA 01810

Six Shattuck Road
Andover, MA 01810

Tel: 978.645.5500
Tel: 800.227.8766 (in U.S.A.)
Web: www.mksinst.com

Tel: 978.975.2350

MKS products provided subject to the US Export Regulations. Diversion or transfer contrary to US law is prohibited.
Specifications are subject to change without notice. mksinst™ is a trademark of MKS Instruments, Inc.