Zhejiang Chengjiu Pipeline Co., Ltd. is one of the most reliable manufacturers and suppliers of slip on pipe flange in China, also supports customized service. Please feel free to buy high quality slip on pipe flange from our factory. Good service and reasonable price are available.
Product Overview
Slip On Pipe Flange is the most widely specified flange type for low-to-medium pressure piping systems, valued for its straightforward installation and reliable sealing performance across a broad range of industrial applications. The pipe slides through the flange bore and is secured with fillet welds on both the bore face and the back face - no pipe-end bevel is required, which reduces fit-up time and lowers installed cost compared to weld neck designs.
At Chengjiu, we manufacture stainless steel slip on pipe flanges in full compliance with EN 1092-1 (PN6 to PN40), ASME B16.5 (Class 150 to Class 1500), DIN 2576, and JIS B2220. Available material grades cover ASTM A182 F304, F304L, F316, F316L, F51 (Duplex 2205), F53 (Super Duplex 2507), and F321. Standard size range is DN15 (NPS ½") to DN600 (NPS 24"); custom larger diameters are accepted.
How a Slip On Pipe Flange Works
The flange bore is machined to match the pipe outer diameter, allowing the pipe to slide through before welding. Two fillet welds - at the bore face and the back face - secure the joint and provide a leak-resistant seal suitable for moderate pressure and temperature service. Because axial position can be adjusted before welding, field alignment is faster and re-work risk is lower than with weld neck flanges.
Product Specifications
Standards & Pressure Ratings
|
Standard |
Type |
Pressure Rating |
Face Type |
|
EN 1092-1 |
Type 01 (Plate / SO) |
PN6, PN10, PN16, PN25, PN40 |
FF (Flat Face) / RF (Raised Face) |
|
ASME B16.5 |
Slip-On (SORF / SOFF) |
Class 150, 300, 600, 900, 1500 |
RF (Raised Face) / FF (Flat Face) |
|
DIN 2576 |
Slip-On / Plate |
PN6, PN10, PN16 |
FF / RF |
|
JIS B2220 |
Slip-On |
5K, 10K, 16K, 20K |
FF / RF |
Material Grades
|
Grade |
UNS No. |
Key Feature |
Typical Application |
|
F304 / F304L |
S30400 / S30403 |
General corrosion resistance |
Water, food, general piping |
|
F316 / F316L |
S31600 / S31603 |
Chloride & acid resistance |
Chemical, marine, pharma |
|
F51 (Duplex 2205) |
S31803 / S32205 |
High strength + corrosion |
Oil & gas, seawater |
|
F53 (S.Duplex 2507) |
S32750 |
Superior chloride resistance |
Offshore, desalination |
|
F321 |
S32100 |
High-temp stabilized |
Heat exchangers |
For full chemical composition and mechanical properties → check our Material Data Sheet
| Dimensional Range | |
|
Parameter |
Range |
|
Nominal Size |
DN15 - DN600 (NPS 1/2" - NPS 24"); larger on request DN15-DN600, |
|
Pressure Class |
PN6 - PN40 (EN); Class 150 - 1500 (ASME) |
|
Facing |
Flat Face (FF), Raised Face (RF) |
|
Surface Finish |
Ra 3.2 - 6.3 um (standard); mirror-polish on request |
|
Test |
Hydrostatic, PMI, MPI / PT, UT available |
Applications
Slip on flanges are the standard choice where moderate pressure service, maintenance access, and installation cost control are priorities.
Water & Wastewater Treatment
Municipal supply networks, desalination pre-treatment, and effluent systems. PN10/PN16 in SS304 or SS316L for potable water and corrosive effluent.
Chemical Processing
Reactor feed lines, solvent transfer, acid/alkali distribution. SS316/316L and Duplex 2205 for chloride-bearing and oxidizing media.
Oil & Gas - Utilities & Auxiliary Lines
Cooling water, instrument air, and low-pressure process lines at onshore facilities where full RT weld inspection is not a project requirement.
Food, Beverage & Pharmaceutical
CIP lines, process water, non-sterile fluid transfer. Mirror-polished RF finish available; SS316L meets FDA and EC 1935/2004 food-contact requirements.
HVAC & Building Services
Chilled water loops, heating circuits, condenser water piping. PN6/PN10 flat face in SS304 widely specified for this service.
Power Generation
Cooling water intake/discharge, auxiliary steam condensate return, and chemical dosing systems.
Slip On vs. Weld Neck Flanges: When to Choose Each
|
Factor |
Slip On Flange |
Weld Neck Flange |
|
Installation ease |
Easy - no pipe bevel required |
Complex - full penetration butt weld |
|
Cost |
Lower material + labour cost |
Higher - more precision required |
|
Pressure rating |
Moderate - up to Class 600 typically |
High - up to Class 2500 |
|
Fatigue resistance |
Good for static service |
Superior for cyclic loads |
|
RT inspection |
Not easily applied |
Full RT inspection possible |
|
Best for |
Low-to-medium pressure, utilities |
High pressure, high temp, cyclic |
From Our Technical Library
Understanding ASME B16 Standards: Which One Applies to Your Project?
Selecting the correct flange standard is one of the most consequential decisions in piping system procurement. ASME B16.5 governs the majority of slip on flange applications in Class 150 through Class 1500 service - covering dimensional requirements, pressure-temperature ratings, and material group classifications that directly affect which flange you can specify. Our technical article ASME B16 Standards Explained: Which One Do You Actually Need? walks through the full B16 family - B16.5, B16.47, B16.9, B16.34, and B16.36 - and explains how each standard interacts when multiple specifications appear in the same project document. If you are sourcing a Slip On Pipe Flange and need to reconcile a mixed-standard piping spec, that article is the practical starting point.
Manufacturing Process
01
Raw material inspection
Incoming billets are verified by PMI (Positive Material Identification) before production begins. Chemical composition is confirmed against the specified grade - no production starts on unverified material.
02
Hot forging
Billets are heated to 1050–1150°C and pressed in closed dies. Forging ensures grain flow aligned with hub geometry and eliminates the porosity risk present in cast or rolled plate.
03
Solution annealing
Heat treatment at 1040–1100°C followed by water quench restores full corrosion resistance and eliminates sensitization.
04
CNC machining
Over 120 CNC and NC machines across large-bore (DN500+) and small-bore (DN10–DN400) turning zones run simultaneously, allowing us to process both large and small diameter orders without scheduling conflicts.
05
Dimensional inspection
100% check against EN 1092-1 or ASME B16.5 drawing: bore, bolt circle diameter, OD, thickness, raised face height, and surface roughness - all measured and recorded per piece.
06
hird-party inspection
SGS, BV, TÜV, or Lloyd's available on request. Inspector access to the production floor is supported at all stages.
07
Marking & packaging
Each flange is marked per EN 1092-1 with heat number, material, standard, rating, and size. Products are rust-protected and packed for sea freight with complete export documents, including invoice, packing list, B/L, COO, and MTC.
OEM & Custom Specifications
Chengjiu accepts OEM orders and non-standard specifications alongside our standard range. In-house forging and CNC machining covers flanges from DN10 to DN5000 (½" to 80") across 0.25 MPa to 42.0 MPa, giving us capacity for custom dimensions outside published standard tables.
Custom options: non-standard bore diameters, special bolt circle configurations, extended hub lengths, custom face finishes (mirror polish, electro-polish, special Ra values), alternative alloy grades. OEM marking, private-label stamping, and project-specific MTC documentation all supported.
Send your drawing or dimensional table to [sale@cncjflange.com] for lead time and pricing.
Packing, Warehouse & Delivery
Packaging
Before shipment, each flange is marked, cleaned, and surface-inspected. Standard sea freight packing uses wooden cases or pallets with VCI film and desiccant. Customized packing - including special crating for oversized flanges or customer-specified marking - is available on request.
Warehouse
Our warehouse operates three dedicated zones: PMI-tested certified billet stock, rough blanks awaiting machining, and finished goods ready for shipment. Standard grades SS304 and SS316L in common sizes are typically available from finished goods stock, reducing lead time on urgent orders.
Delivery
CNCJ exports to customers in more than 30 countries across five continents. Nearest export ports: Ningbo / Shanghai, with regular consolidated and full-container shipments to all major global destinations. Supported trade terms: FOB, CIF, EXW.
Standard Lead Time
- Standard stocked sizes (PN10/PN16, ASME Class 150/300): 7–15 business days
- Custom sizes, high-alloy grades (Duplex / Super Duplex), large-diameter flanges: 3–6 weeks
Why Source from Chengjiu
Founded 2012 · ISO 9001:2015 · ISO 14001 · ISO 45001
- Full in-house forging, machining, and heat treatment - no subcontracting for critical processes
- 13,000 m² factory · 120+ CNC & NC machines · 50+ production staff · 10,000 t/yr output
- EN 10204 3.1 / 3.2 MTRs standard; hydrostatic testing, PMI, NDT (PT/MT/UT) available
- Third-party inspection by SGS, BV, TÜV, or your nominated inspector supported
- OEM and custom specifications accepted; ASME, EN, DIN, JIS, GOST, AS standards supported
- Exports to 30+ countries; Ningbo/Shanghai port; FOB, CIF, EXW
FAQ
Q: What is the maximum pressure rating for a stainless steel slip on pipe flange?
A: Under ASME B16.5, a Class 300 F316L slip on flange has a cold working pressure of approximately 51.1 bar (740 psi) at 38°C. EN 1092-1 PN40 is rated at 40 bar at ambient temperature. Pressure ratings decrease at elevated temperatures - always consult the P-T rating tables in the applicable standard for your service conditions.
Q: Can slip on flanges be used for steam service?
A: Yes, with conditions. Verify that the flange class and material grade meet pressure-temperature requirements at actual steam conditions. ASME B31.1 limits use of slip-on flanges in Class 300 and above for cyclic steam service; weld neck flanges are generally preferred above 260°C.
Q: What gasket should I use?
A: For raised face (RF) flanges, spiral wound gaskets (SWG) with 316L winding are standard for most industrial services. For flat face (FF) flanges in low-pressure water or chemical service, EPDM or PTFE sheet gaskets are common. Always match gasket material to process fluid and operating temperature.
Q: Do you provide mill test reports and third-party inspection?
A: Yes. All flanges are supplied with EN 10204 3.1 or 3.2 MTRs as standard. Third-party inspection by SGS, BV, TÜV, or your nominated inspector is accommodated on request. PMI testing is available for every heat.
Q: What is your standard lead time?
A: Standard stocked sizes in PN10/PN16 and ASME Class 150/300 typically ship within 7–15 business days. Custom sizes, high-alloy grades (Duplex/Super Duplex), or large-diameter flanges require 3–6 weeks. Contact our sales team for a precise lead time quotation based on your specification.
Q: What trade terms do you support?
A: FOB Ningbo/Shanghai, CIF, and EXW are all supported. We handle all export documentation including commercial invoice, packing list, bill of lading, certificate of origin, and MTC.
Hot Tags: slip on pipe flange, China slip on pipe flange manufacturers, suppliers, factory, stainless steel flange, 2 1 2 threaded flange, blind flange 3, flange type 05, sae socket weld flange, ansi 400 flange dimensions
