Why do many galvanized steel pipes have pores on their surface?

1. Due to the low thermal resistance during the manufacturing process of plastic-coated steel pipes, the liquid tends to cool rapidly during forging. Additionally, the design of the exhaust structure is irregular, leading to a difficulty in expeditiously expelling gases.

2. The paint on the plastic-coated steel pipe has poor exhaustiveness, possibly due to the paint's own insufficient volatility. Another reason is that the storage of raw materials is not standardized, and there was no preheating during the application process.

3. The blockage of air holes may also be due to an unsatisfactory surface lubrication of the metal or improper cleaning of rust, the use of non-standard deoxidizing agents during production, or inadequate replenishment or handling during usage.

Due to the high adaptability of plastic-coated steel pipes, their functional characteristics have been recognized. Therefore, the jointing of such pipes requires careful study. Specific jointing methods:

During the pipeline connection process, it is strictly forbidden to have water nearby. Once in contact with water, it accelerates the rusting of the steel pipe, which can cause certain damage. Therefore, during the connection process, the cross-section cannot come into contact with water, and plastic-coated pipe fittings cannot be replaced by non-plastic coated pipe fittings. The injection-molded joints should be mounted on flanged steel with raised threads, and transition pieces should be selected for connecting with the valve threads. Some transition pieces should also be used for connecting with the water supply, and rubber sealing rings are required for the groove connections. After we have finalized the transition plan, we need to start using different raw materials to facilitate the subsequent connection steps. Pay attention to be careful during this process; mistakes are not permitted. When pushing the plastic-coated steel pipe into the heating furnace for heat treatment, be mindful of the time and do not neglect the time and heat. Additionally, the performance of the plastic-coated composite steel pipe is relatively stable, and the steel pipe needs to maintain a tight bond with the inner and outer plastic coatings over time. These pipes are widely present in our daily lives, bringing many conveniences to our production and daily life.

The above explains the causes of air holes on the surface of plastic-coated steel pipes and the methods of connection. As long as we follow the correct standards for installation and arrangement, there should be no issues. We hope the information provided assists you! Thank you for reading!