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Appendix A: Product Specifications
ASA Flange Specifications
35
ASA Flange Specifications
(Continued)
Valve Type Number
253B-
4-4-2
253B-
6-4-2
253B-
6-6-2
253B-
8-6-2
253B-
8-8-2
253B-
10-10-2
Inside Diameter (A)*
Inches
(mm)
3.965
(100.7)
5.781
(146.8)
5.781
(146.8)
7.501
(190.5)
7.501
(190.5)
10.000
(254.0)
Mounting Flange
ASA 4”
ASA 4”
ASA 6”
ASA 6”
ASA 8” ASA 10”
Outside Diameter (B)*
Inches
(mm)
8.90
(226.1)
8.90
(226.1)
10.90
(276.9)
10.90
(276.9)
13.19
(335.0)
16.00
(406.4)
Controllable
Conductance (l/sec)
min
max
1.50
950
TBD
TBD
TBD
TBD
TBD
TBD
TBD
TBD
TBD
TBD
Closed Leakage
(Torr l/sec)
N/A
N/A
N/A
N/A
N/A
N/A
Flapper Seal**
None
None
None
None
None
None
Thickness (C)*
Inches
(mm)
0.88
(22.4)
0.88
(22.4)
0.94
(23.9)
0.94
(23.9)
0.94
(23.9)
0.94
(23.9)
Overall Height
Inches
(mm)
13.74
(349.0)
13.74
(349.0)
15.74
(399.8)
15.74
(399.8)
18.03
(458.0)
20.84
(529.3)
No. of Bolt Holes
8
8
8
8
8
12
Bolt Hole
Diameter (D)*
Inches
(mm)
0.75
(19.1)
0.75
(19.1)
0.88
(22.4)
0.88
(22.4)
0.88
(22.4)
1.00
(25.4)
Bolt Circle Diameter
Inches
(mm)
7.500
(190.9)
7.500
(190.9)
9.500
(241.3)
9.500
(241.3)
11.750
(298.5)
14.250
(362.0)
Flange O-ring groove
ID
In
(mm)
Parker
®
No. or
Size (JIS)
5.995
(152.3)
2-258
5.995
(152.3)
2-258
8.000
(203.2)
2-266
8.000
(203.2)
2-266
9.734
(247.2)
2-273
11.938
(303.2)
2-278
* Refer to Figure 1, page 23.
** 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...