The production process of expansion joints (compensators) varies depending on their material, design, and application, but generally includes several key steps. The following is the general production process flow of metal corrugated expansion joints, and some special processes of rubber expansion joints:
Production process flow of metal corrugated expansion joint:
blanking: Cut the raw material to the desired length and shape according to the design drawing.
coiled tube: Crimp the sheet into a cylindrical shape, which is suitable for preliminary forming of bellows.
Assembly weld longitudinal seam: Weld the edges of the crimped sheet together to form a continuous tubular structure.
Radiographic detection (RT detection): Use X-ray or gamma-ray to check the quality of the weld to ensure that there are no defects such as cracks and pores.
Assembly mold: Install the corrugation mold inside the tubular structure and prepare for the next corrugation.
Hydroforming: Injecting high-pressure liquid into the mold to make the tube wall expand outward to form corrugations.
Appearance inspection: Check the appearance of the corrugations to make sure there are no noticeable damages or irregularities.
mold removal: Remove the mold from the expansion joint.
inspect: Includes further non-destructive testing of the corrugated sections, such as radiographic testing, to ensure all welds and corrugations are up to standard.
End bevel machining: Machining both ends of the expansion joint to facilitate subsequent welding.
Pickling passivation: Use pickling paste or solution to remove surface oxide layer and improve corrosion resistance.
package: The final step is to package the finished product to protect the product from damage during transportation and storage.
Production process of rubber expansion joint:
The production process of rubber expansion joint is different from that of metal corrugated expansion joint, mainly including the following steps:
Material preparation: Selection of suitable rubber formulations, which may include natural rubber, synthetic rubber, or mixtures thereof, as well as reinforcing materials such as nylon cords or steel wire braided mesh.
kneading: Mix the rubber and additives to form a homogeneous rubber mixture.
Forming: Place the rubber mixture into a mold and mold it using a hard mold or air mold. Air molding is generally believed to yield better product quality.
Vulcanization: The formed rubber part is placed under high temperature and pressure to solidify and form a stable structure.
Assembly: Assemble vulcanized rubber balls with metal components such as flanges to form complete expansion joints.
testing: Carry out pressure test, tensile test, etc. on the finished product to ensure that the performance of the expansion joint meets the design requirements.
Packaging and labeling: Finalize the final packaging and identification, ready for delivery to the customer.
Each type of expansion joint may also have some special handling and inspection steps during the specific production process to ensure product quality and performance.