Applications of Seamless Stainless Steel Pipes in Fishing Vessels

Fishing vessels are the core carriers of marine fishery production. They operate year-round in harsh ocean environments characterized by high salinity, humidity, and strong corrosion, while also enduring wave impact, mechanical vibration, and temperature fluctuations. These demanding conditions place extremely high requirements on the durability and reliability of onboard components.

Among them, HAOMEI seamless stainless steel pipes have become indispensable materials in fishing vessel construction and maintenance. Thanks to their seamless structure, corrosion resistance, high strength, and excellent formability, they are widely used across critical systems-from power transmission to fish preservation, and from structural support to fluid transport.

Why Are Seamless Stainless Steel Pipes Preferred in Fishing Vessels?

In marine environments, ordinary carbon steel pipes are highly susceptible to corrosion, while welded stainless steel pipes may face the risk of electrochemical corrosion at the weld seam. Seamless stainless steel pipes (TP304, TP316L, etc.) are manufactured through integral piercing and drawing, eliminating the weaknesses of weld seams. Under the same wall thickness conditions, seamless pipes have a pressure resistance rating 15-30% higher than welded pipes, while completely avoiding the risk of intergranular corrosion that may occur in the weld area. Therefore, in critical operating conditions involving high-pressure fluids, high-temperature steam, and corrosive media, seamless stainless steel pipes are often the irreplaceable choice.

HAOMEI Aluminum manufactures marine seamless stainless steel pipes ranging in length from 4-8 meters and wall thickness from 3-40 mm, which can be processed using hot rolling and cold drawing processes to meet different precision requirements.

Production Processes

The two main manufacturing methods are hot rolling (hot extrusion) and cold drawing (cold rolling), often combined for optimal performance.

1. Hot Rolling (Hot Extrusion)

Hot rolling is primarily used for large-diameter and thick-wall pipes.

Process flow:
Billet preparation → Heating → Piercing → Rolling/Extrusion → Sizing → Cooling → Straightening → Inspection

The standard specifications for hot-rolled tubes are typically: outer diameter 54-480mm, wall thickness 4.5-45mm. Due to the high-temperature forming process, the surface precision of hot-rolled tubes is relatively limited, making them suitable for applications such as fluid transport and structural support where dimensional tolerances are not critical.

2. Cold Drawing (Cold Rolling)

For higher precision, thinner walls, and better surface finish:

Process flow:
Mother pipe → Heading → Annealing → Pickling → Lubrication → Multi-pass cold drawing → Heat treatment → Straightening → Inspection

Cold-drawn tubes are available in a range of specifications: outer diameter 6-200mm, wall thickness 0.5-21mm. Their dimensional accuracy and surface finish are significantly better than those of hot-rolled tubes, making them the preferred choice for precision machinery, instrument piping, and hydraulic systems.

Advantages of Marine Seamless Stainless Steel Pipes

1. Superior Corrosion Resistance
   Especially TP316L, which offers excellent resistance to chloride-induced pitting.

2. High Pressure Resistance
   Seamless structure ensures safe operation under high pressure.

3. Smooth Inner Surface
   Reduces flow resistance and minimizes fouling from marine organisms.

4. Wide Temperature Range
   Maintains toughness at -196°C and stability up to 800°C.

5. Eco-Friendly & Recyclable
   100% recyclable with lower lifecycle emissions than coated carbon steel.

Product Specifications

Applications in Fishing Vessels

1. Hull Structure & Support

Seamless pipes are used in structural frameworks due to their high strength and load-bearing capacity, ensuring vessel stability under harsh sea conditions.

2. Piping Systems

Fishing vessels have numerous piping systems, such as oil pipes, cooling pipes, water supply pipes, and drainage pipes. These pipes typically need to withstand the corrosive effects of seawater and salt spray for extended periods. Seamless steel pipes, with their excellent corrosion resistance, are commonly used in various marine piping systems.

3. Power and Transmission Systems

The power and transmission systems of fishing vessels require stable operation over long periods. The high strength and good compressive strength of seamless steel pipes make them ideal materials for this purpose. Seamless steel pipes are commonly used in drive shafts, support shafts, and drive systems.

4. Fishing Net Systems and Equipment

Modern fishing vessels are typically equipped with complex fishing net systems for fishing, lifting, and other operations. Seamless steel pipes are frequently used in the supports and transmission systems of these devices to improve their stability and durability.

5. Living and Refrigeration Systems

In addition to fishing systems, fishing vessels also require living facilities and refrigeration systems. Seamless steel pipes are used in the vessel's water treatment, refrigeration systems, and living pipelines to ensure the convenience of the crew and the preservation of the catch.

Anti-Corrosion Enhancement Measures in Marine Environments

• Passivation Treatment
  Forms a dense Cr₂O₃ layer, improving corrosion resistance by 3–5 times

• Electropolishing
  Reduces surface roughness (Ra ≤ 0.2 μm), minimizing chloride adhesion

• Sealing Optimization
  Use of fluororubber or PTFE seals to prevent crevice corrosion

• Regular Freshwater Cleaning
  Removes salt deposits and maintains protective oxide film

About HAOMEI

As a leading global supplier of industrial piping materials, HAOMEI Aluminum Co., Ltd. specializes in providing high-quality seamless stainless steel pipe solutions for shipbuilding and marine engineering.

Our products include TP304, TP316L, and other grades, manufactured in strict compliance with ASTM A312 and major classification society standards.

Beyond supplying premium products, we offer comprehensive technical support, from material selection to after-sales service.

Choose HAOMEI to build a reliable, durable, and corrosion-resistant system for your fishing vessel operations.