NS3304 Seamless Pipe

With a nickel-molybdenum-chromium-tungsten alloy composition and extremely low carbon content, NS3304 delivers outstanding resistance in highly corrosive environments where stainless steel and conventional alloys cannot provide reliable service.

Typical chemical composition features include:
● Molybdenum: 15–17%
● Chromium: 14.5–16.5%
● Tungsten: 3.0–4.5%
● Carbon: ≤0.010%

This balanced chemistry allows NS3304 seamless pipe to withstand severe reducing and oxidizing media, including hydrochloric acid, sulfuric acid, hydrofluoric acid, phosphoric acid, and chloride-containing solutions.

Key Advantages of NS3304 Seamless Pipe

1.Excellent Resistance to Severe Corrosion

NS3304, as the Chinese equivalent of Hastelloy C-276, is specifically designed for environments involving multiple corrosion mechanisms.

The alloy provides excellent resistance against:
● Pitting corrosion
● Crevice corrosion
● Chloride stress corrosion cracking
● Intergranular corrosion
● Oxidizing and reducing acid attack

Compared with stainless steel grades such as 316L and duplex alloys, NS3304 offers significantly higher reliability in mixed acid, wet chlorine, and high-chloride environments.

2.Seamless Structure for Improved Safety

The hot extrusion process creates a continuous metal structure without welded joints. Compared with welded nickel alloy pipe, NS3304 seamless pipe provides:

● No longitudinal weld seam
● No weld heat-affected zone
● Uniform corrosion resistance around the circumference
● Consistent mechanical properties along the pipe wall

This makes the pipe especially suitable for pressure-containing systems where weld defects or localized corrosion could lead to unexpected maintenance or downtime.

The uniform structure also allows engineers to optimize wall thickness while maintaining required safety margins, helping reduce material weight and long-term operating costs.

Main Applications

1.Chemical Processing Equipment

Chemical plants commonly use NS3304 seamless pipe for applications involving aggressive acids and mixed chemical media.

Typical applications include:
● Chemical reactors
● Acid transportation piping
● Heat exchangers
● Process equipment

The alloy maintains performance in hydrochloric acid, sulfuric acid, and other highly corrosive environments.

2.Flue Gas Desulfurization Systems

FGD equipment is exposed to wet-dry cycling, chlorides, and acidic compounds that can rapidly damage conventional materials.

NS3304 seamless pipe is commonly used in:
● Absorber spray zones
● Scrubber piping
● Corrosive gas treatment systems

3.Pharmaceutical and Pulp & Paper Industries

The alloy is suitable for industries requiring both corrosion resistance and reliable process hygiene.

Applications include:
● Pharmaceutical reactors
● Clean-in-place (CIP) piping
● Chlorine dioxide bleaching equipment
● Chemical washing systems

4.Offshore and Marine Systems

Offshore environments combine hydrogen sulfide, carbon dioxide, chloride ions, and seawater exposure.

NS3304 seamless pipe is used for:
● Produced-water injection lines
● Seawater heat exchangers
● Offshore corrosion-resistant piping

Its resistance to chloride corrosion provides advantages over stainless steel and duplex alternatives in long-term marine service.

Manufacturing Process and Quality Control

Ji Lai Damanufactures NS3304 seamless pipe through a controlled production process from billet preparation to final inspection.

The manufacturing process includes: 1.Nickel alloy billet preparation 2.Hot extrusion forming 3.Solution annealing 4.Straightening 5.Non-destructive testing 6.Final dimensional inspection

Hot extrusion forms continuous grain flow along the pipe wall, improving structural consistency and reducing the risk of defects associated with welded manufacturing routes.

Each shipment includes complete quality documentation:
● EN 10204 3.1 Mill Test Certificate
● Heat number traceability
● Chemical composition report
● Mechanical testing results
● Inspection records

Custom Dimensions and Direct Factory Supply

Jiangsu Ji Lai Da Nickel-Based Alloy Co., Ltd. supplies NS3304 seamless pipe in standard and customized dimensions.

Available options include:
● Custom OD × wall thickness combinations
● Different length requirements
● Surface finishing options
● Project-specific inspection requirements
● The extrusion process allows tooling adjustments between production campaigns, enabling customized sizes without excessive one-time production costs.

Specification at a Glance

FAQ

Q: Can NS3304 seamless pipe replace welded C-276 pipe in the same service?

A: Yes. The seamless structure provides equal or better corrosion resistance at every point on the circumference, and the absence of a weld seam removes the most common initiation site for pitting and cracking.

Q: What is the minimum order quantity?

A: Jiangsu Ji Lai Da Nickel-Based Alloy Co., Ltd. quotes mill-run quantities starting from 500 kg per size. For smaller volumes, contact the supplier for a quotation based on available stock.

Q: Are dual-certified MTCs available?

A: Every heat is tested and certified to ASTM B619 and GB/T 15009 simultaneously. The EN 10204 3.1 certificate lists both standards on one page.

Q: How does NS3304 differ from NS3305?

A: NS3305 corresponds to Hastelloy C-22 (UNS N06022), which has higher chromium and lower molybdenum. NS3304 (C-276) excels in reducing acids; NS3304 seamless pipe is the more common choice when chlorides and sulfuric acid are both present.