Sealing element outside diameter (mm) 1½"" — ASME B16.20
Sealing element outside diameter (mm) 1½"" to ASME B16.20: dn 40, class 150–600 69.9 mm, class 900–2500 69.9 mm.
Dimensions of Sealing element outside diameter (mm) 1½""
| Symbol | Dimension | Value |
|---|---|---|
| · | DN | 40 |
| · | Class 150–600 | 69.9 mm (2.752 in) |
| · | Class 900–2500 | 69.9 mm (2.752 in) |
SKU TSH-GASKET-ASME-B16-20-1½" · Standard ASME B16.20 · teshi-web
Purchase description
SEALING ELEMENT OUTSIDE DIAMETER (MM), 1½"", SS316 + GRAPHITE, CS RINGS, ASME B16.20
Available materials: SS316 + graphite, CS rings, SS316 + PTFE, CNAF (non-asbestos), Neoprene / EPDM rubber, Soft iron / SS316 (ring joint).
Notes
- Dimensions are in millimetres unless stated otherwise.
- For Class 900, NPS ½" to 2½", the Class 1500 gasket is used.
- Class 2500 is listed to NPS 12" only.
- Inner ring inside diameters have been revised between editions of ASME B16.20 and are not tabulated here; ask for the value to the edition your project specifies.
- Nominal sealing element thickness is 4.5 mm (0.175").
Other sizes — Sealing element outside diameter (mm), Standard
½""¾""1""1¼""2""2½""3""4""5""6""8""10""12""14""16""18""20""24""
Frequently asked questions
What are the main types of pipe flanges?
Weld neck (WN), slip-on (SO), blind (BL), socket weld (SW), threaded (THD), lap joint (LJ) and plate flanges. Special types include orifice, long weld neck, reducing flanges and spectacle blinds.
When should I use a weld neck flange instead of a slip-on?
Use weld neck flanges for high pressure, high or cycling temperature, and lines with vibration or fatigue loading. The tapered hub and full-penetration butt weld spread stress smoothly. Slip-on flanges are cheaper and easier to align, but their fatigue life is roughly one third of a WN.
What does Class 150, 300 or 600 mean on a flange?
The ASME class is a pressure-rating designation, not a pressure in psi. The allowable pressure depends on the material group and temperature. A Class 150 A105 flange is rated 19.6 bar at 38 °C but 13.8 bar at 200 °C.
Is a 150# flange rated for 150 psi?
No. A Class 150 carbon-steel flange is rated about 285 psi (19.6 bar) at ambient temperature, and about 170 psi (11.7 bar) at 260 °C. The "150" is a class number.