Plate Flange (PL)
Flat-type flange with simple structure, light weight and low cost — ideal for low-pressure pipeline systems.
View DetailsLoading…
Socket Weld Flange (SW)
Socket bore flange with fillet weld — compact and reliable for small-bore, high-pressure systems.
All flange types
SWSteel Pipe Flanges
Overview
Socket Weld Flange (SW) is a flange with a socket structure, which inserts the pipe into the flange socket and fixes it by fillet welding. It has the advantages of compact structure, small volume, reliable sealing and strong pressure resistance, and is suitable for small-diameter, high-pressure pipeline systems. As a high-performance flange type for small-diameter pipelines, it is widely used in high-pressure, high-precision industrial pipeline systems and export projects worldwide.
Size Range
½" – 4" (DN15 – DN100)
Pressure Class
Class 300 – 2500 / PN25 – PN100
Key Features
- Compact structure — small volume and light weight for narrow installation spaces
- Reliable sealing and high pressure resistance via socket bore and fillet weld
- Smooth internal flow — pipe seated in socket with low-resistance transition
- Easy installation — socket design aids alignment and welding quality
- Global standard compliance — ISO, ASME, DIN, EN, JIS and GB manufacturing
- Sealing surfaces: RF, FF and RTJ
- Custom materials and sizes per drawing and working conditions
Benefits
- Strong fillet-weld joint in a compact envelope
- Reduced turbulence and no thread crevices for fluid accumulation
- Ideal for high-pressure small-bore service up to Class 2500
- Customized per customer drawings, materials and standards
Specifications
| Standards | ISO 7005, ASME B16.5, DIN 2501, EN 1092-1, JIS B2220, GB/T 9117, HG/T 20592, HG/T 20615 |
| Materials | Carbon steel (A105, 20#), stainless steel (304, 316L), alloy steel (16Mn, 15CrMo, F11) — customizable per medium and conditions |
| Pressure Ratings | Class 300, 600, 900, 1500, 2500 / PN25, PN40, PN63, PN100 |
| Nominal Diameter | DN15 – DN100 (NPS ½" – 4") |
| Sealing Surface | RF (Raised Face), FF (Flat Face), RTJ (Ring Type Joint) |
| Working Temperature | -40°C – 550°C (high-temperature grades on request) |
| Connection | Socket bore with fillet weld per ASME B16.11 |
Applications
Petroleum and petrochemical small-bore pipingNatural gas and power generation systemsChemical engineering and nuclear energyHigh-pressure instrumentation and process linesSystems requiring smooth flow and tight sealing
Product Enquiry
Standards
- • ISO 7005
- • ASME B16.5
- • DIN 2501
- • EN 1092-1
- • JIS B2220
- • GB/T 9117
- • HG/T 20592
- • HG/T 20615
Materials
- • Carbon Steel: A105, 20#
- • Stainless Steel: 304, 316L
- • Alloy Steel: 16Mn, 15CrMo, F11
Related Products
Slip On Flange (SO)
Sleeve-type flange slipped over the pipe and fixed by fillet welding — economical for medium and low pressure systems.
View Details
Lap Joint Flange (LJ)
Loose flange with stub end — convenient disassembly for large-diameter, low and medium pressure systems.
View DetailsReady to Source Premium Flanges?
Get a competitive quote with full technical specifications and material certificates.