Dimensions Spectacle Blinds - ASME B16.48


flanges

 
PRESSURE CLASS 150
NPSOutside
A
Inside
B
Center Line
C
THK
t
Web Width
W
1/2451660338
3/4542170338
1642780338
7342906.438
83481006.438
2102611206.451
107731406.451
3133891506.464
1591021759.764
41721141909.764
51941412159.776
621916824012.776
827621930012.776
1033727336015.7102
1240632443019.1102
1444835647519.1108
1651140646022.4108
1854645758025.4114
2060350863528.4121
2471461075031.8140
NPSOutside
A
Inside
B
Center Line
C
THK
t
Web Width
W
PRESSURE CLASS 600
NPSOutside
A
Inside
B
Center Line
C
THK
t
Web Width
W
1/25116656.438
3/46421806.438
17027906.457
79371009.757
92431159.767
2108551259.757
1276715012.767
31468317012.767
1599618515.776
419110821515.776
523813526519.186
626416229022.486
831821235028.495
1039726543035.1105
1245431549041.1105
1448934652544.5114
1656239760550.8124
1861044865553.8133
2067949772563.5133
2478759784073.2152
NPSOutside
A
Inside
B
Center Line
C
THK
t
Web Width
W
PRESSURE CLASS 900
NPSOutside
A
Inside
B
Center Line
C
THK
t
Web Width
W
1/26016806.438
3/46721906.441
176271006.457
86371109.757
95431259.767
21405516512.757
1626719012.767
31658319015.767
420310823519.176
524413528022.486
628616232025.486
835621239535.195
1043226547041.1105
1249531553547.8105
1451834656053.8114
1657239761560.5124
1863544868566.5133
2069649775073.2133
2483559790088.9152
NPSOutside
A
Inside
B
Center Line
C
THK
t
Web Width
W
PRESSURE CLASS 1500
NPSOutside
A
Inside
B
Center Line
C
THK
t
Web Width
W
1/26116806.438
3/46721909.741
176271009.764
86351109.764
954112512.770
21405316512.770
1626319015.776
31727820519.176
420610224022.489
525112829028.489
627915432035.189
834920339541.1102
1043225548050.8114
1251830357060.5114
1457533363566.5127
1663838170576.2133
1870242977585.9146
2075247883095.3152
24899575990111.3178
NPSOutside
A
Inside
B
Center Line
C
THK
t
Web Width
W
PRESSURE CLASS 2500
NPSOutside
A
Inside
B
Center Line
C
THK
t
Web Width
W
1/26716909.738
3/47321959.741
183271109.764
1023513012.764
1144114515.770
21435317015.770
1656319519.176
31947823022.476
423210227528.489
527612832535.189
631415437041.189
838419844053.8102
1047324854066.5114
1254628962079.2114
NPSOutside
A
Inside
B
Center Line
C
THK
t
Web Width
W
 

 

General Notes:

  • Dimensions are in millimeters unless otherwise indicated.
  • D = Hole size (where required) should be the same as the flange bolt hole. In practice, these dimensions have been rounded round off upwards.
  • Wt = Thickness of the web (or tie bar) should be 6 mm minimum, or equal to Thickness (t) if less than 6 mm. Spectacle Blinds should be made from a plate or forging specification, approved for use by ASME B31.3, of essentially the same chemical composition as the mating flanges and piping involved
  • Spectacle Blinds according to ASME B16.48 may be used for installation between ASME B16.5 flanges
  • Depending on a customer specification, some dimensions can be different from what on this page is defined.

REMARK(S) OF THE AUTHOR...

RAISED FACE JOINT BLANKS
images
  • ASME B16.48 says: The gasket seating surface finish and dimensions for raised face line blanks shall be in accordance with ASME B16.5. A raised face may be specified at the option of the purchaser.
  • A Raised Face would add machining time and complexity so the price would be higher. Call this the Bugatti or Rolls Royce of the line blind world.
  • Personally, I have seen that version once or twice somewhere. The version without Raised Face is the default and is used everywhere.