Slip On Neck Flange | Professional Non-Standard Custom Manufacturer
Slip On Neck Flange (SO Flange) is a commonly used medium and low pressure pipe connection fitting in industrial piping systems. Its performance and structure sit between plate slip-on flanges and weld neck flanges, delivering a perfect balance of cost performance and structural stability. As a professional flange manufacturer based in Cangzhou, we specialize in producing standard slip on neck flanges in accordance with Chinese, American, German and Japanese standards. We also provide custom processing for large-diameter, thick-walled, special bolt pitch and special-shaped non-standard slip on neck flanges. Customization based on drawings and samples is available, with all products supplied directly from the factory without middlemen markup.
1. Features of Slip On Neck Flange
Compared with ordinary plate slip-on flanges, slip on neck flanges adopt an integrally forged tapered neck structure, which greatly improves overall rigidity and pressure resistance and effectively reduces pipeline deformation under stress. Different from the full penetration welding of weld neck flanges, slip on neck flanges adopt socket slip welding technology. Pipes are inserted into the flange inner diameter and welded on both sides, enabling simple operation and high construction efficiency for fast on-site installation.
Manufactured by integral forging, the flange features dense internal structure, no pores or sand holes and excellent deformation resistance. With precise bolt hole positions and smooth sealing faces, it effectively avoids assembly deviation and sealing leakage during on-site installation, perfectly suitable for most normal-temperature, medium and low-pressure industrial piping conditions.
2. Common Materials and Specifications
We customize slip on neck flanges with different materials according to pipeline medium, pressure and service environment to adapt to conventional and slightly corrosive working conditions:
- Carbon Steel Slip On Neck Flange: 20#, Q235B, A105, 16Mn. Featuring stable material performance and high cost performance, it is widely used in water supply, heating, general oil and gas, ventilation and other medium and low-pressure pipelines.
- Stainless Steel Slip On Neck Flange: 304, 316L, 321, 2205 duplex steel. With excellent rust resistance, acid and alkali resistance and corrosion resistance, it is applied in chemical, pharmaceutical, sewage treatment and seawater service pipelines.
- Alloy Steel Slip On Neck Flange: High-temperature resistant materials such as 15CrMo and 12Cr1MoV, suitable for medium-pressure and slightly high-temperature auxiliary pipelines in power stations and industrial equipment.
Specification coverage: Conventional sizes DN15-DN3000 and customized large-diameter products; Pressure grades include PN10, PN16, PN25, PN40, PN64 and American standard Class150, Class300 and other mainstream medium and low-pressure grades.
3. Implementation Standards and Sealing Types
All our slip on neck flanges are produced in strict accordance with domestic and international industry standards, supporting domestic engineering projects and export orders. Main applicable standards include: GB/T9116, HG/T20592, ASME B16.5, EN1092, JIS B2220, etc.
A full range of customizable sealing faces are available, including RF (Raised Face), FF (Full Face) and MFM (Male and Female Face). Among them, RF slip on neck flanges are the most widely used. They can be matched with ordinary rubber gaskets, PTFE gaskets and spiral wound gaskets, featuring low procurement cost and convenient later maintenance.
4. Working Conditions and Application Scope
With convenient welding, high rigidity, stable sealing and moderate price, slip on neck flanges are mainly used for pipe projects with normal temperature, small temperature fluctuation, medium and low pressure and no severe vibration impact, serving as the preferred choice for civil and general industrial pipelines:
- Municipal engineering: Water supply, heating, fire protection and sewage treatment pipeline systems
- General industry: Factory circulating water, ventilation, medium and low-pressure oil and gas transmission pipelines
- Light industry: Supporting pipelines for food, pharmaceutical, daily chemical and environmental protection equipment
- Mechanical and electrical equipment: Connecting flanges for pump and valve ports and mechanical equipment
- Chemical industry: Normal temperature and atmospheric pressure pipelines for slightly corrosive chemical medium transmission
5. Our Production and Customization Advantages
Equipped with complete independent production lines including forging, CNC machining and quality inspection, we meet diverse procurement demands for standard spot wholesale and non-standard engineering customization:
1. Mature and stable technology: Integrally forged blanks and precision CNC turning ensure smooth sealing faces and accurate bolt hole spacing, achieving perfect on-site fitting and eliminating water and air leakage problems.
2. Powerful non-standard customization: We can customize large-diameter, thick-walled, special-shaped flanges with special bolt pitches and exclusive sealing faces. No mold opening is required, and both small trial orders and large-scale engineering orders are acceptable.
3. Strict and traceable quality inspection: Each batch of products is equipped with material certificates and factory inspection reports. Dimension re-inspection and non-destructive testing are available on demand to meet the requirements of domestic project acceptance and export customs clearance.
4. High cost performance and stable delivery: Direct factory sales eliminate intermediate profits. Sufficient stock for standard specifications and controllable production cycle for customized products ensure no delay to project progress.
6. Common Purchasing FAQs
Q: How to choose between slip on neck flange and weld neck flange?
A: Slip on neck flanges are preferred for ordinary working conditions with medium and low pressure and normal temperature due to simple installation and lower cost. Weld neck flanges with better sealing performance and fatigue resistance are recommended for key pipelines with high temperature, high pressure, flammable and explosive media and severe vibration.
Q: Can you produce non-standard large-diameter slip on neck flanges?
A: Yes. We support full-range non-standard customization. Flanges with special sizes, special pressure grades, thickened and widened structures and special shapes can be precisely produced according to customer drawings.
Q: Can you provide complete acceptance documents?
A: We can provide complete documents including product certificates, material test reports, dimension inspection reports and NDT reports free of charge, supporting project acceptance and export customs clearance.
Inquiry & Cooperation
Whether you need in-stock standard slip on neck flanges or custom non-standard products for engineering projects, simply provide your drawings, dimensions, materials and pressure parameters. Our technical team will verify specifications and calculate costs for free, and provide accurate quotations promptly. We welcome long-term cooperation with engineering companies, trading enterprises and terminal manufacturers at home and abroad.