Product Overview
Carbon steel slip-on flange is a flat, circular forging or plate flange that slips over the pipe and is welded on both the inside and outside to form a connection. It is one of the most economical and widely used flange types in low-pressure and medium-pressure piping. Slip-on flanges are specified by ASME B16.5 (NPS 1/2″ – 24″) and ASME B16.47 Series A/B (NPS 26″ – 60″), as well as EN 1092-1 Type 01. Huaxia-Steel supplies slip-on flanges from NPS 1/2″ to NPS 60″ in Class 150 – 2500 and PN6 – PN400, in A105, A105N, A350 LF2, P250GH, P245GH, and equivalent grades.
Specifications
| Parameter | Range | Standard / Tolerance |
|---|---|---|
| Size | 1/2″ – 60″ (DN15 – DN1500) | ASME B16.5 / B16.47, EN 1092-1 |
| Pressure class | Class 150 – 2500, PN6 – PN400 | Per standard rating tables |
| Bore | Slip-over pipe OD | Bore tolerance per B16.5 |
| Facing | Raised face (RF), flat face (FF), ring joint (RTJ) | Standard finish serrated 125 – 250 AARH |
| Wall / hub | Matched to pipe schedule | Hub dimensions per standard |
| Marking | Size, class, grade, heat number, standard | Stamped or inked |
Available Grades
| Standard | Grade | Service |
|---|---|---|
| ASTM A105 | A105 / A105N | Ambient and high-temperature carbon steel |
| ASTM A350 | LF2, LF3 | Low-temperature service |
| EN 1092-1 | P250GH, P245GH | European pressure equipment |
| JIS B2220 | SOP, SFF | Japanese standard piping |
Manufacturing Standards
- Forging: forged or rolled from killed carbon steel billets; normalized or normalized and tempered.
- Machining: CNC turning to standard face, bore, bolt circle, and hub dimensions; serrated finish on RF.
- Heat treatment: normalizing standard for A105N; A105 without N may be acceptable in some jurisdictions but normalizing improves toughness and machinability.
- Dimensional standard: ASME B16.5 covers NPS 1/2″ – 24″; ASME B16.47 covers NPS 26″ – 60″.
Applications
- Water, oil, and gas low-pressure pipelines
- HVAC and fire protection systems
- Refinery and chemical process piping
- Power plant utility lines
- Shipbuilding and marine piping
Quality Assurance
- EN 10204 3.1 certificate: chemistry, tensile, heat treatment
- Dimensional inspection: OD, bore, bolt circle, thickness, facing finish
- Surface and NDE: MT/PT on forgings; UT on request for large classes
- Positive material identification (PMI) optional
- Third-party inspection (SGS, BV, TÜV) welcomed
Packaging & Shipping
- Plywood cases or steel pallets; cardboard separators between flanges
- Plastic bolt-hole protectors and facing protectors
- Container or bulk shipment with tally and photos
Huaxia-Steel supplies carbon steel slip-on flanges to ASME B16.5, B16.47, EN 1092-1, and JIS B2220 — Class 150 to 2500, PN6 to PN400, factory-direct with full certification. Send us your flange list with size, class, facing, and grade for a same-day quotation.
