Appendix B: Model Code Explanation
Model Code
43
Type 253 with CF Flanges
Type
Number
Nominal Inside
Diameter
inches (mm)
CF Flange Size
Flapper
O-Ring
253B-20-2CF-1
0.779 (20)
2¾”
Yes
253B-20-2CF-2
0.779 (20)
2¾”
No
253B-1-2CF-1
1.270 (32)
2¾”
Yes
253B-1-2CF-2
1.270 (32)
2¾”
No
253B-2-3CF-1
1.888 (48)
3
3
/
8
”
Yes
253B-2-3CF-2
2.000 (51)
3
3
/
8
”
No
253B-2-4CF-1
2.000 (51)
4½”
Yes
253B-2-4CF-2
2.000 (51)
4½”
No
253B-3-6CF-2
3.000 (76)
6”
No
253B-4-6CF-2
3.875 (98)
6”
No
Type 253 with JIS Flanges
Type
Number
Nominal Inside
Diameter
inches (mm)
JIS Flange Size
Flapper
O-Ring
253B-2-50J-1
1.888 (48)
JIS-50
Yes
253B-2-50J-2
2.000 (51)
JIS-50
No
253B-4-100J-2
3.875 (98)
JIS-100
No
Summary of Contents for 253B-1-2CF-1
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