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Forged Pipe Fittings Duplex Stainless Steel Bushing ASTM A815 UNS S31803 1/8"-4" ASME B16.11
| Material Grade | ASTM A694 F42 | Mechanicalstrength | High Tensile Strength |
|---|---|---|---|
| Thread | BSPP BSPT NPT | Heat Treatment | Normalizing, Quenching & Tempering |
| Head Code | Hexagonal | Class Rate | 3000/6000/9000 |
| Class Rating | 3000LB/6000LB | Pressure Rating | 2000 Lbs - 9000 Lbs |
| Usage | Oil Gas Pipe Fittings Connector | Material | Carbon Steel, Stainless Steel, Alloy Steel |
| Function | Piping Connection | Thread Standard | ASME B1.20.1 / BS21.0 |
| Color | Metallic (Silver, Gray, Black Depending On Material And Finish) |
Forged Pipe Fittings Duplex Stainless Steel Bushing ASTM A815 UNS S31803 1/8"-4" ASME B16.11
1. Product Description
This product is a forged pipe fitting bushing manufactured from UNS S31803 (Duplex 2205 / F51) stainless steel in accordance with ASME B16.11 and MSS SP-79/83/95/97 standards. A bushing is a pipe fitting used to connect two pipes or fittings of different sizes, featuring a male thread on the smaller end and a female thread on the larger end . UNS S31803 is a dual-phase stainless steel with a microstructure of approximately 50% austenite and 50% ferrite, offering roughly double the yield strength of standard 300-series austenitic stainless steels while providing exceptional corrosion resistance . As a forged fitting, it is produced by shaping solid steel billets under high pressure, resulting in a tighter grain structure and superior performance under pressure and thermal cycling . This bushing is designed for threaded (NPT) connections in small-bore piping systems.
2. Key Product Parameters
| Parameter | Details / Range |
|---|---|
| Material Standard | ASTM A815 / ASME SA815 |
| Dimensional Standard | ASME B16.11, MSS SP-79/83/95/97 |
| Material Grade | UNS S31803 (Duplex 2205 / F51 / WNR 1.4462) |
| Type | Threaded Bushing (Male-to-Female reducer) |
| Size Range | 1/8" – 4" NB (DN6 – DN100) |
| Pressure Classes | 2000#, 3000#, 6000# |
| Thread Type | NPT (ASME B1.20.1), BSPT, BSPP |
| Chemical Composition | Cr: 21.0-23.0%, Ni: 4.5-6.5%, Mo: 2.5-3.5%, N: 0.08-0.20%, Fe: Balance |
| Tensile Strength (min) | 620–800 MPa (90–116 ksi) |
| Yield Strength 0.2% (min) | 450–550 MPa (65–80 ksi) |
| Elongation (min) | 25% |
| Hardness (max) | 293 HBW / 31 HRC |
| Density | ~7.8 g/cm³ |
| PREN Value | ~34–36 |
| Heat Treatment | Solution annealing at 1020-1100°C, water quench |
3. Application / Usage
This bushing is ideal for high-pressure and corrosive fluid systems requiring threaded transitions between different pipe sizes:
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Oil & Gas: Offshore platforms, subsea piping, high-pressure process lines, wellhead connections
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Chemical Processing: Chloride-containing acids, brine services, heat exchangers
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Marine Engineering: Seawater piping systems, desalination plants
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Power Generation: Cooling water systems, high-temperature service
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Instrumentation: Piping connections requiring size reduction at valves, pumps, or equipment
4. Advantages
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Superior Strength: Yield strength is approximately double that of 316L austenitic steel, enabling thinner wall designs
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Excellent Corrosion Resistance: PREN ~34-36 provides outstanding resistance to pitting, crevice corrosion, and chloride stress corrosion cracking
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Threaded Convenience: No welding required; fast installation and easiest disassembly for maintenance
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Forged Integrity: Tighter grain structure than cast fittings; superior performance under pressure and vibration
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Cost-Effective: Higher strength offsets material cost premium over austenitic grades in critical service
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Versatile Installation: Male thread on small end, female thread on large end allows for direct size reduction at pipe joints
5. Functions
The threaded bushing provides a reliable, leak-proof mechanical transition between two pipes or fittings of different diameters within a piping system. It features a male NPT thread on the smaller end (inserted into a female fitting) and a female NPT thread on the larger end (receiving a male pipe end). This design allows for direct size reduction at connection points, eliminating the need for additional adapters or reducing fittings.
6. Installation Instructions
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Preparation: Clean both male and female threads thoroughly; remove all dirt, oil, and debris
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Thread Sealant: Apply PTFE tape or pipe dope to the male threads (small end) and to the male threads of the pipe that will engage with the bushing's female end
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Thread Engagement (Male End): Screw the small end (male threads) into the mating female fitting by hand, then tighten with a wrench to appropriate torque
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Thread Engagement (Female End): Screw the larger pipe's male threads into the bushing's female end by hand, then tighten with a wrench
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Avoid Over-tightening: Do not exceed recommended torque to prevent cracking the fitting body
7. Precautions
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Thread Compatibility: NPT, BSPT, and BSPP threads are not interchangeable. Verify thread type per system specification
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Temperature Limitation: Not recommended for use above 300°C or below -50°C due to reduced toughness
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Ferrite Balance: Ensure proper material specification to maintain the 50/50 austenite-ferrite microstructure
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Vibration Sensitivity: Threaded fittings are not recommended on lines subject to significant vibration, thermal shock, or hazardous fluid service
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Stress Concentration: Threading creates stress concentrators; verify suitability for the specific service environment
8. Shipping & Delivery
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Standard delivery time is typically 15–30 days, subject to order quantity and specification availability
9. Payment Terms
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Common international payment methods include T/T (Telegraphic Transfer) and L/C at sight (Letter of Credit)
10. Packaging
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Products are securely packed in plywood cases or wooden crates with internal cushioning to ensure safe transportation and prevent damage during transit
11. After-Sales / Return & Warranty Policy
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All products undergo strict quality inspection before shipment, with Mill Test Certificates (EN 10204 3.1/3.2) available
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In case of quality issues, retain original packaging and provide relevant photos or third-party inspection reports
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Specific return, exchange, and warranty terms are subject to the final sales contract agreement.
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FAQ
1. Are you trading company or manufacturer ?
We are manufacturer ,You can see the certification.
2. How long is your delivery time?
Generally it is 5-10 days if the goods are in stock. or it is 15-20 days if the goods are not in stock, it is according to quantity.
3. Do you provide samples ? is it free or extra ?
Yes, we could offer the sample for free charge but need pay the cost of freight.
4. What is your terms of payment ?
Payment<=1000USD, 100% in advance. Payment>=1000USD, 50% T/T in advance ,balance before shippment.

