Multi-Core Stainless Steel Seamless Tube For Shipbuilding

Material

A multi-core tube (also called a multi-line tube bundle) is a prefabricated assembly that integrates multiple seamless stainless steel tube “cores” inside one extruded plastic protective jacket. It is designed to route hydraulic, pneumatic, lubrication, and instrumentation lines through tight shipboard spaces with fewer clamps, joints, and installation steps.

Specifications

• Construction: 2–12 stainless tube cores bundled (parallel or helical) inside a common outer sheath (plastic jacket).

• Core tube materials (typical options): 304L / 316L / Duplex 2205 / Super Duplex 2507 / 904L (others on request).

• Core tube sizes (typical ship bundle range): OD 3–12 mm; wall 0.5–2.0 mm (customizable).

• Delivery form: straight lengths or coils; long continuous lengths can reduce field joints and potential leak points.

• Outer jacket materials (typical): PVC / TPU / PE / PP / PVDF (and similar thermoplastics), selected by temperature, chemical exposure, and abrasion needs.

• Identification: color coding / numbering / laser marking per core for fast hook-up and maintenance.

• Testing (typical): hydrostatic / pneumatic / eddy current / helium leak (per project criticality).

Key Features

• Space-saving line management: multiple circuits in one routed bundle instead of many separate tube runs.

• Corrosion-resistant tube cores: stainless/duplex grades suited for marine humidity and chloride exposure (grade selection depends on severity).

• Plastic jacket protection: impact/abrasion buffer and easier handling during installation and operation.

• Fewer connections: long coils and bundled routing help reduce cutting/welding/fittings.

Our Advantages

1. “Will it survive seawater/chlorides and prevent premature corrosion?”
   We offer a grade ladder (316L → 2205 → 2507 → 904L) so you can match the tube core alloy to chloride severity. For aggressive chloride service and seawater handling, super duplex 2507 is designed for seawater/process systems and umbilical hydraulic/process tubing, with strong pitting resistance and strong SCC resistance.

2. “How do you reduce leak risk in long shipboard runs?”
   Leak risk is driven by joints, ovality/tolerances, and installation handling. Using long continuous coils and minimizing field joints is a proven approach for control-line style tubing. In addition, high-integrity hydraulic/instrumentation tubing is commonly supplied with smooth surfaces and close tolerances to improve coupling performance and reduce leakage risk.

3. “Will the outer coating actually protect the bundle during installation and service?”
   A polymer encapsulation/jacket acts as a protective cushion, improving handling and providing impact protection; it also reduces metal-on-metal contact and helps the bundle slide more easily during routing. Jacket material can be chosen (PP/PE/PVDF, etc.) to match temperature and chemical exposure.

Chemical Composition

Mechanical Properties

Applicable Standards

• ASTM: A269; A789/A790

• EN: EN 10216-5; EN 10088 series

• GOST: GOST 9941

• JIS: JIS G3459; JIS G3463

• GB: GB/T 13296; GB/T 14976 

Application Fields

Main fields: shipbuilding, marine & offshore platforms, and related fluid/control systems where corrosion resistance, compact routing, and reliability matter.

Typical shipboard uses (examples):

• Hydraulic control: steering, stabilizers, hatch/door actuation, deck machinery control circuits.

• Pneumatic/automation: air control lines and valve actuation signals.

• Instrumentation: pressure/temperature impulse lines and monitoring connections.

• Offshore/subsea interfaces (when applicable): umbilical-style hydraulic and chemical injection/control lines.

Q: Are you trading company or manufacturer ?

A: manufacturer,also can do trading.

Q: How long is your delivery time?

A: Generally speaking,it is 10-15 days if the goods are in stock,or it is 30-40 days if the goods are not in stock,

it is according to quantity.

Q: Do you provide samples? is it free or extra ?

A: Yes, we could offer the sample for free charge but need pay the cost of freight.

Q: What is your terms of payment ?

A: Payment<=2000USD, 100% in advance. Payment>=2000USD, 30% T/T in advance ,balance before shippment.

If you have another question, pls feel free to contact with me.