Detailed explanation of pipeline insulation construction specifications and standards
Pipeline insulation construction is an important link in industrial and civil buildings, and its specifications and standards involve multiple aspects such as material selection, construction technology, and acceptance requirements. The following is a detailed explanation based on national standards and industry norms:
1、 National standards
Main national standards:
The Construction Specification for Industrial Equipment and Pipeline Insulation Engineering (GB50126-2008) is applicable to industrial equipment and pipeline insulation engineering with an external surface temperature of -196~+850 ℃, and specifies construction requirements, material selection, process standards, and other contents.
General Principles for Insulation Technology of Equipment and Pipelines (GB/T 4272-2008): Provide basic requirements and guiding principles for insulation technology.
Design Code for Thermal Insulation Engineering of Industrial Equipment and Pipelines (GB 50274-2013): covers the technical requirements for thermal insulation engineering design.
Scope of application:
Insulation construction of outdoor and indoor heating pipelines (including steam and water media) for newly constructed, renovated, and expanded industrial and civil buildings.
Not suitable for pipeline insulation under special working conditions such as high temperature, high pressure, and strong corrosion.
2、 Industry standards
Petrochemical industry:
Technical Specification for Thermal Insulation of Petrochemical Equipment and Pipelines (SH3010-2000): The outer surface temperature of the insulation layer is required to be ≤ 60 ℃, and generally controlled to be ≤ 50 ℃.
Anti scald insulation range: within 2.1m above the ground or operating platform, and less than 0.75m from the operating surface.
Construction industry:
The insulation of HVAC pipelines should be made of materials with low thermal conductivity, low water absorption, resistance to aging, and environmental friendliness, such as glass wool, rubber, etc.
The joint of insulation materials shall not exceed 2mm, and the height shall not exceed 1.5mm.
3、 Material requirements
Performance of insulation materials:
Thermal conductivity: insulation layer ≤ 0.10W/(m · K), cold insulation layer ≤ 0.064W/(m · K).
Density: Insulation hard material ≤ 220kg/m ³, insulation cold material ≤ 180kg/m ³.
Compressive strength: For hard insulation products, the compressive strength should be ≥ 0.4MPa, and for cold insulation products, the compressive strength should be ≥ 0.15MPa.
Common material types:
Precast tiles: foam concrete, perlite, vermiculite, asbestos tiles, etc.
Pipe shell products: rock wool, slag wool, glass wool, rigid polyurethane foam, etc.
Coil material: polystyrene foam plastic, rock wool, etc.
4、 Construction process requirements
Basic process:
Surface treatment of pipelines → cutting of insulation materials → installation and fixation → construction of protective layer → acceptance.
The insulation of pipelines and equipment should only be carried out after passing the anti-corrosion and hydrostatic tests.
Key process points:
Single layer staggered seams, filled with soft materials of the same operating temperature between the seams.
The insulation material is tied with double stranded galvanized iron wire, with a spacing of no more than 300mm.
The elbow area can be insulated with soft materials of the same temperature, or with expansion joints left in hard materials.
Special part treatment:
Flanges, valves and other parts need to reserve loading and unloading gaps, and after overall insulation, local treatment should be carried out.
The corners of square equipment should be made into cover type lap joints, and vertical through joints should not be formed.
5、 Acceptance criteria
Quality requirements:
The insulation layer should be flat and the joints should be tight; Soft materials require compacted interfaces.
The protective layer should be made of color steel plate, hard aluminum alloy plate or stainless steel plate, with a thickness that meets the design requirements.
Testing method:
The thickness of the insulation layer, the tightness of the wrapping layer, and the treatment of the joints need to be inspected and measured.
100% non-destructive testing of welds shall be carried out in accordance with the "Acceptance Specification for Urban Heating Pipeline Network".
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