Quality control of 3PE composite pipes is a comprehensive process involving multiple stages and aspects. Below are the detailed steps for quality control of 3PE composite pipes in terms of raw materials, production process, finished product inspection, and subsequent handling:
Raw Material Quality Control
1.1 Quality Control of Epoxy Powder, Adhesive, and Polyethylene:
Ensure that these raw materials are sourced from reliable suppliers and comply with relevant standards and specifications.
Conduct quality inspections on raw materials, including checks on their physical properties, chemical composition, adhesive strength, and other key indicators.
Monitor the storage environment of raw materials to prevent moisture, contamination, or deterioration.
1.2 Quality Control of Steel Pipes:
Strictly inspect incoming steel pipes, including verification of pipe diameter, wall thickness, pipe number, and manufacturer's certificate of quality.
Check the steel pipe surface for defects such as scratches, dents, etc., and ensure smooth transitions in welds with a surplus height not exceeding specified values.
Perform necessary cleaning and derusting treatments on steel pipes to improve the adhesion of the anticorrosive coating.
Quality Control During Production Process
2.1 Steel Pipe Surface Treatment:
Preheat steel pipes using a preheating device to enhance derusting effectiveness.
Thoroughly clean the steel pipe surface using shot blasting equipment to ensure the required surface cleanliness.
Conduct roughness tests on the derusted steel pipe surface to ensure that the anchor pattern depth falls within the specified range.
2.2 Application of Anticorrosive Coating:
Strictly control the spraying temperature, speed, and thickness of the epoxy powder to ensure a uniform coating free of bubbles and cracks.
The adhesive shall be wrapped uniformly without any missed areas to improve the overall performance of the anticorrosive coating.
The polyethylene shall be tightly wrapped without wrinkles to ensure the integrity and seal of the anticorrosive coating.
2.3 Molding Process Control:
Strictly control process parameters such as conveyor line speed, steel pipe heating temperature, and heating temperatures of the adhesive and polyethylene.
Conduct visual inspections on the molded anticorrosive coating to ensure no defects such as pits, bubbles, or wrinkles.
Finished Product Inspection
3.1 Inspection of Coating Performance:
Use an electric spark leak detector to check the anticorrosive coating for leaks, ensuring no leakage points.
Test the bonding strength, impact resistance, chemical resistance, and other properties of the anticorrosive coating.
3.2 Visual Inspection:
Conduct visual inspections on finished 3PE composite pipes, including coating color, gloss, and uniformity.
Check if the pipe end treatment is smooth and if the bevel processing meets requirements.
3.3 Dimension and Specification Inspection:
Measure the dimensions and specifications of the finished pipes to ensure compliance with design requirements and relevant standards.
Subsequent Handling
4.1 Pipe End Treatment:
Perform special treatments on pipe ends, such as controlling the length of reserved ends and chamfering the end face of the polyethylene layer.
4.2 Packaging and Storage:
Properly package finished 3PE composite pipes to prevent damage during transportation and storage.
The storage environment should be dry, well-ventilated, and free of corrosive gases to prevent aging or damage to the anticorrosive coating.
Quality Records and Traceability
Establish a complete quality record system to document raw material inspection, production process control, and finished product inspection.
Implement quality traceability to ensure rapid identification of causes and implementation of measures for improvement in case of quality issues.
