Sewage engineering procurement of steel bellows, how to distinguish the quality of raw materials

In the construction of sewage projects, steel bellows have become one of the core pipes of the drainage system due to their high strength and corrosion resistance. However, the quality of raw materials varies, which directly affects the operation and maintenance effect of the project. It is necessary to master practical identification methods when purchasing. First look at the appearance: the surface of steel bellows made of high-quality raw materials is smooth and uniform, the color is consistent, and there are no variegated spots, bubbles or bumps. The steel belt and plastic layer are tightly bonded, and there is no layered gap. Pipes produced from inferior raw materials are prone to color difference, local irregularities, and the steel belt layer may be loose, and even have obvious splicing marks. Secondly, touch feeling: the thickness of the high-quality pipe wall is uniform, it can rebound quickly after pressing, and the surface has no burrs and roughness; inferior pipes often have thin pipe walls, which are easy to deform when pressed, and some areas have prickly rough edges, which feel light and floating. Furthermore, do a simple combustion test: take a small amount of pipe scraps and ignite them. When the high-quality raw materials burn, the flame is stable, the smoke color is light, and the smell is close to the mild taste of paraffin burning. After burning, the residual ash is less and finely broken; when the inferior raw materials burn, the flame jumps violently, accompanied by thick black smoke, and emits a pungent plastic odor. The residual agglomeration is hard and not easy to crush. Finally, check the raw material label: regular products will clearly label the raw material ingredients (such as high-density polyethylene), without ambiguity or false labeling; if the label is missing or the content is ambiguous, there is a high probability of using inferior or recycled raw materials. When purchasing, comprehensive multi-dimensional testing is required, not just looking at the price, to ensure that the selected steel belt bellows meet the standards, in order to ensure the long-term stable operation of sewage projects.