I. Overview of Steel jacket insulation pipe for high temperature steam
Steel jacket insulation pipe for high temperature steam is an insulated piping system designed specifically for transporting high-temperature, high-pressure steam or thermal oil.
Comprising a working steel pipe, an insulation layer, and a steel outer jacket, it offers excellent thermal insulation, high-temperature and pressure resistance, long-term corrosion resistance, and low heat loss.
This pipe is widely used in thermal power plants, chemical plants, industrial parks, and urban central heating trunk lines, ensuring safe and stable transportation of high-temperature media while improving energy efficiency and reducing operating costs.
II. High temperature steam steel jacket insulation pipe structure
(1) Working steel pipe
It bears the pressure of steam or thermal oil and is the main body of the conveying medium.
The material is generally 16Mn, Q345B, 20#, which can withstand high temperature and high pressure.
(2) Inner anti-corrosion layer (optional)
Prevents the medium from corroding the inside of the steel pipe.
Commonly used are epoxy resin, epoxy powder or lined steel pipe.
(3) Insulation layer
The main insulation layer is usually made of inorganic fiber, glass wool, silicate or composite material.
The thermal conductivity is low and the thickness is selected according to the temperature and heat loss requirements.
(4) Sealing layer (optional)
Fill the space between the steel pipe and the outer sheath with sealing material or inorganic fiber to prevent the insulation layer from becoming loose or forming thermal bridges.
(5) Steel outer sheath
Provides mechanical protection, corrosion resistance, and waterproofing.
Material: low carbon steel or stainless steel, thickness 3-6 mm.
(6) External anti-corrosion layer (optional)
The outer sheath surface can be sprayed with epoxy, coal tar or 3PE to enhance corrosion resistance.
(7) Interface and sealing components
Sleeve, flange or welded interface to ensure the sealing and thermal integrity of the pipeline connection.
This is especially important for long-distance pipelines and directly buried pipelines.
III. Implementation Standards for Steel Jacket Insulation Pipes for High-Temperature Steam
i. ISO 15650:2012 – Design and construction of industrial piping systems
Scope of application: Applicable to the design, construction and acceptance of industrial piping systems.
Relevance: Provides general requirements for the design and construction of piping systems and can serve as a reference for the design and construction of high-temperature steam steel jacketed insulated pipes.
ii. ISO 9001:2015 – Quality Management Systems
Scope: Quality management system requirements applicable to any organization.
Relevance: Ensures manufacturing processes comply with international quality management standards, improving product quality and customer satisfaction.
iii. EN 13480 – Metallic Industrial Piping Systems
Scope: Applicable to the design, manufacture, installation, and acceptance of metallic industrial piping systems.
Relevance: Provides detailed design and manufacturing requirements for metallic piping systems and serves as a reference for high-temperature steam steel jacketed insulated pipes.
IV. Application Fields and Selection Guide for Steel Jacket Insulation Pipes for High-Temperature Steam
i. Thermal Power Plants and Power Plants
Application: Transports boiler steam to turbines or heat exchange systems.
Selection Reference:
Operating Temperature: ≤250°C
Pressure: ≤4.0 MPa
Recommended: High-strength carbon steel or alloy steel working tube, polyurethane or high-temperature inorganic fiber insulation, and a steel outer sheath.
ii. Industrial Steam System
Application: High-temperature steam transportation in industrial plants such as chemical, papermaking, and food processing.
Selection Reference:
Operating Temperature: 180-250°C
Pressure: ≤3.0 MPa
Internal anti-corrosion coating (epoxy coating or stainless steel inner tube) can be selected based on the corrosiveness of the medium.
iii. District Heating (Urban Heating Network)
Application: Centralized steam transportation to various user heat exchange stations.
Selection Reference:
Pipe diameters up to DN1200 are available to meet long-distance transmission requirements.
Insulation thickness can be selected from 80 to 150 mm, depending on the allowable heat loss.
Outer sheaths can be HDPE or steel-in-steel to ensure waterproof and corrosion resistance for direct-buried pipelines.
iv. Process circulation system
Applications: Circulating steam or hot oil transport in industrial production, such as refining, chemical reactors, and heat treatment equipment.
Selection Reference:
For high-temperature and high-pressure media, a steel-jacketed steel structure is recommended.
Insulation materials should include high-temperature-resistant inorganic fibers or high-temperature polyurethane composites.
To ensure controlled expansion and displacement of the pipeline, use sliding supports or guide rings.
V. Frequently Asked Questions about Purchasing Steel Jacket Insulation Pipes for High-Temperature Steam
i. What media are suitable for Steel jacket insulation pipes for high-temperature steam?
A: Suitable for high-temperature steam, thermal oil, and industrial circulating hot water. Medium temperatures typically range from 150°C to 250°C, and pressures can reach 4.0 MPa. The working tube material and internal corrosion protection layer should be selected based on the corrosiveness of the medium.
ii. How to choose the appropriate working steel pipe material and wall thickness?
A: The pipe diameter is determined based on steam temperature, pressure, and pipe size. Generally, pipes from DN20 to DN1200 can be made from 16Mn, Q345B, or 20# steel pipes. Wall thickness increases with pressure to ensure safe operation of the pipeline.
iii. How to determine the thickness of the insulation layer?
A: The thickness is generally 50 to 150 mm, depending on the steam temperature, allowable heat loss, and construction environment. The higher the temperature or the longer the transport distance, the thicker the insulation layer should be.
iv. How to choose the outer sheath material?
A: Direct buried pipelines often use HDPE or steel-jacketed steel outer sheaths; overhead or outdoor pipelines can choose galvanized steel or stainless steel sheaths, and corrosion resistance, waterproofing and mechanical protection requirements must be considered.
v. What are the types of pipeline interfaces? How to choose?
A: The main types of joints are sleeve welding, flange connection and welded joints. Long-distance steam pipelines usually use sleeve welding or welded joints to ensure sealing and thermal insulation integrity.
vi. What standards and certifications should I pay attention to when purchasing?
A: For domestic use, please refer to GB/T 23257-2017 and CJ/T 114-2000. For export or international projects, it is recommended to refer to the EN 15632 series of standards to ensure compliance with engineering specifications and international quality requirements.
vii. How to judge whether the pipeline anti-corrosion performance meets the requirements?
A: Check the outer sheath anti-corrosion layer material and thickness (epoxy, 3PE, or HDPE), construction process, and quality inspection report. You can also choose an outer anti-corrosion coating or a steel jacketed steel structure for enhanced durability.
viii. What precautions should be taken during transportation and storage?
Pipes should be placed horizontally to avoid heavy pressure or impact.
Avoid exposure to rain or prolonged sunlight.
Pipe openings should be sealed to prevent foreign matter from entering.
The insulation layer and outer sheath should be protected from scratches and damage to ensure effective insulation after installation.
