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Appendix A: Product Specifications
NW Style ISO Flange Specifications
37
NW Style ISO Flange Specifications
Valve Type Number
253B-
60-63-1
253B-
60-63-2
253B-
3-80-2
253B-
4-100-2
253B-
6-160-2
253B-
8-200-2
253B-
10-250-2
Inside Diameter (A)*
Inches
(mm)
2.362
(60.0)
2.362
(60.0)
3.000
(76.2)
3.875
(98.4)
5.750
(146.1)
7.650
(194.3)
9.700
(246.4)
Mounting Flange
NW-63
NW-63
NW-80
NW-100
NW-160
NW-200
NW-250
Outside Diameter (B)*
Inches
(mm)
5.95
(151.1)
5.95
(151.1)
5.95
(151.1)
7.40
(188.0)
8.90
(226.1)
11.22
(285.0)
13.19
(335.0)
Controllable
Conductance (l/sec)
min
max
TBD
TBD
0.80
375
1.00
500
1.50
900
TBD
TBD
TBD
TBD
TBD
TBD
Closed Leakage
(Torr l/sec)
<10
-7
N/A
N/A
N/A
N/A
N/A
N/A
Flapper Seal**
Viton
None
None
None
None
None
None
Thickness (C)*
Inches
(mm)
0.81
(20.6)
0.81
(20.6)
0.81
(20.6)
0.94
(23.9)
0.94
(23.9)
0.94
(23.9)
0.94
(23.9)
Overall Height
Inches
(mm)
10.79
(274.1)
10.79
(274.1)
10.79
(274.1)
12.24
(310.9)
13.74
(349.0)
16.06
(407.9)
18.03
(458)
No. of Bolt Holes
4
4
8
8
8
12
12
Bolt Hole
Diameter (D)*
Inches
(mm)
0.35
(8.89)
0.35
(8.89)
0.35
(8.89)
0.35
(8.89)
0.43
(10.9)
0.43
(10.9)
0.43
(10.9)
Bolt Circle Diameter
Inches
(mm)
4.330
(110.0)
4.330
(110.0)
4.920
(125.0)
5.710
(145.0)
7.870
(199.9)
10.240
(260.1)
12.200
(309.9)
Flange O-ring groove
ID
N/A
N/A
N/A
N/A
N/A
N/A
N/A
* Refer to Figure 3, page 24.
** Where Viton is used, other materials are available; consult factory.
Summary of Contents for 253B-1-2CF-1
Page 3: ...118843 P1 Rev C 2 99 MKS Type 253B Exhaust Throttle Valve...
Page 8: ...List of Figures and Tables vi...
Page 40: ...Maintenance Chapter Four Maintenance 32 This page intentionally left blank...
Page 52: ...Model Code Appendix B Model Code Explanation 44 This page intentionally left blank...