MKS 253B-1-2CF-1, Instruction Manual

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JIS Flange Specifications Appendix A: Product Specifications
40
JIS Flange Specifications
Valve Type Number 253B-
2-50J-1
253B
2-50J-2
253B
4-100J-2
Inside Diameter (A)*
Inches
(mm) 1.888
(48.0)
2.000
(50.8)
3.875
(98.4)
Mounting Flange 2¾” CF JIS 50 mm JIS 100 mm
Outside Diameter (B)*
Inches
(mm)
4.47
(113.5)
4.47
(113.5)
7.40
(188.0)
Controllable
Conductance (l/sec)
min
max
0.35
300
0.70
300
1.50
900
Closed Leakage
(Torr l/sec)
<10
-7
N/A N/A
Flapper Seal** Viton None None
Thickness (C)*
Inches
(mm)
1.00
(25.4)
1.00
(25.4)
0.94
(23.9)
Overall Height
Inches
(mm) 10.36
(263.0)
10.36
(263.0)
13.29
(337.6)
No. of Bolt Holes
6 4 8
Bolt Hole Diameter (D)*
Inches
(mm) 0.39
(9.91)
0.39
(9.91)
0.47
(11.9)
Bolt Circle Diameter
Inches
(mm)
3.937
(100)
3.937
(100)
6.299
(160)
Flange O-ring groove ID
In
(mm)
Parker
®
No. or
Size (JIS)
2.766
(70.26)
2.765 x 0.157
(70 x (4)
2.766
(70.26)
2.765 x 0.157
(70 x (4)
2.766
(70.26)
2.765 x 0.157
(70 x (4)
* Refer to Figure 5, page 25.
** Where Viton is used, other materials are available; consult factory.
Due to continuing research and development activities, these product specifications are subject to change without notice.