Steel Jacketed Preinsulated Pipe

Published:2025-08-14 | Last Updated: 2025-08-30    Views: 118

I. Structure of steel-jacketed pre-insulated pipes

(1) Working pipe

Located in the inner layer.

Used for conveying media such as steam, hot water, and hot oil.

Common materials include seamless steel pipes, spiral welded steel pipes, and straight seam steel pipes.

High pressure resistance and excellent high-temperature performance.

(2) Insulation layer

Located between the working pipe and the outer pipe.

Common materials include composite silica, rock wool, and polyurethane foam.

Low thermal conductivity, providing significant insulation performance.  

Thickness can be adjusted according to design requirements.  

(3) Outer Steel Pipe  

Located on the outer layer.  

Provides protective functions, preventing damage from groundwater, soil pressure, and mechanical impact.  

Common materials include SSAW steel pipes or LSAW steel pipes with corrosion protection treatment applied to the outer surface.

II. Applications and Scope of Steel sleeve insulated steel pipes

(1) Urban District Heating Projects

Steel-clad insulated pipes are widely used for long-distance transportation of hot water and steam. Underground installation not only effectively minimizes heat loss but also ensures safe and stable transportation.

(2) Industrial Park Heating Networks

In industrial sectors requiring continuous heat sources—such as chemical plants and paper mills—double-walled steel-jacketed buried insulated pipes deliver superior high-temperature and moisture resistance, meeting long-term operational demands in complex environments.

(3) Power Plant Pipeline Systems

Steam transportation from boilers to workshops demands exceptionally high insulation performance Double-wall insulated steel pipe deliver outstanding thermal insulation, significantly reducing energy consumption and enhancing overall energy efficiency.

(4) Other Application Areas

Beyond the scenarios above, steel-jacketed insulated pipes are also suitable for specialized pipeline projects requiring high corrosion resistance, waterproofing, and thermal insulation, demonstrating extensive applicability.

III. Advantages of Steel Jacketed Preinsulated Pipe

（1）Excellent Thermal Insulation

With low thermal conductivity pre insulated pipes effectively minimize heat loss. Energy dissipation during transportation is negligible, achieving high energy efficiency.

（2）High Durability

The robust outer steel pipe structure withstands significant external pressure. Additionally, corrosion-resistant treatment substantially extends the pipeline's service life.

（3）Wide Adaptability

These heating steam pipe operate stably in both high-temperature and low-temperature environments. Suitable for both underground and overhead installations, they offer flexible application scenarios.

（4）Low Maintenance Costs

The robust integrated structure requires minimal additional maintenance during operation, substantially reducing long-term operational and maintenance expenses.

IV. Considerations for Purchasing Steel Jacketed Preinsulated Pipe

(1) Specifications and Dimensions

Determine nominal diameter, working pipe wall thickness, insulation layer thickness, and outer pipe specifications based on design drawings.

Refer to the general specification table and select models according to requirements. For high-pressure transmission, choose seamless carbon steel pipes to ensure safety.

(2) Material Selection

The working pipe material must meet the requirements of the medium and pressure.

Polyurethane insulated steel pipes are suitable for normal-temperature hot water; silicone or rock wool is recommended for high-temperature steam.

(3) Anti-Corrosion Requirements

The anti-corrosion coating of the outer protective pipe must be suitable for underground environments.

Common processes include 3PE, IPN8710, and epoxy coal tar asphalt Steel-in-steel insulated steel pipes feature a robust structure and excellent anti-corrosion performance.

(4) Production Qualifications and Testing

Select manufacturers with valid certifications.

Ensure products pass pressure testing and thermal insulation performance testing.

(5) Transportation and Storage

Protect the anti-corrosion coating during transport.

Store in a dry, level location, shielded from direct sunlight and rain.

V. Steel Jacketed Preinsulated Pipe Installation Procedure

VI. Recommendations for Use and Maintenance of Steel Jacketed Preinsulated Pipes

(1) Regular Inspections

Check pipe joints for signs of ground settlement or water seepage.

Inspect the integrity of the anti-corrosion coating to prevent premature damage that could compromise insulation performance.

(2) Prevent Mechanical Damage

Avoid stacking heavy objects or conducting excavation work above pre-insulated steel-jacketed pipes.

Protect pipe surfaces during construction or handling to prevent scratches or impacts.

(3) Promptly Repair Damaged Areas

Immediately repair any damage to the anti-corrosion coating to ensure long-term protection.

Prevent moisture ingress into the insulation layer to maintain thermal performance.