Seamless pipes fall under Chapter 73 of the HS Code system, titled “Articles of Iron and Steel.” Specifically, they are categorized under heading 7304, which pertains to "Seamless iron (other than cast iron) or steel pipes, tubes, and hollow sections." This heading is further divided into subheadings based on characteristics such as diameter, thickness, and material composition. This article will briefly introduce HS codes 7304 for import and export of seamless pipes.

Cold Drawn Seamless Tubes (CDS) are widely utilized in applications that demand exceptional strength and resistance to high pressure. In comparison to hot-finished seamless tubes, CDS offers tighter tolerances and superior mechanical properties, making them ideal for mechanical use. These tubes are particularly favored in the hydraulic industry for manufacturing chrome-plated telescopic cylinders and hydraulic rods. Additionally, they are commonly employed in the production of large-diameter, thick-walled, high-pressure hydraulic cylinders. Cold drawn seamless tubes are also integral to the manufacturing of heavy-duty equipment, including cranes and garbage trucks. Below is a detailed size chart for cold drawn seamless tubes.

Galvanized steel pipes are steel pipes coated with a layer of zinc, which serves as a protective barrier against corrosion, significantly extending their service life. This zinc layer acts as a solid "protective armor" for the steel pipe, safeguarding it from the damaging effects of environmental erosion. This article will briefly introduce application of galvanized steel pipes in power engineering.

The petrochemical industry is a vital pillar of the national economy, involving complex production processes that often operate under harsh and extreme conditions. Throughout the oil refining and chemical product synthesis stages, the pipeline system must endure high temperatures, high pressures, and severe corrosive environments. This article will briefly introduce seamless steel pipes in the petrochemical industry.

In recent years, with the continuous improvement of welding processes for large diameter spiral steel pipes (SSAW), their processing quality and performance have significantly improved. As the variety of such pipes increases, there is now a noticeable gap in the quality of these pipes available on the market. So, what factors determine the quality of large diameter spiral steel pipes?

Domestic manufacturers of LSAW (Longitudinal Submerged Arc Welded) pipes often enhance the material's properties by adding alloys. After the cold drawing process, stress annealing is essential to eliminate residual stresses in the material, which helps prevent fractures in the LSAW pipes. This article will briefly introduce breakage prevention methods of straight seam welded pipe.

Rubber lining is a process in which a rubber-based material, typically in the form of sheets or extruded tubes, is applied to the internal surface of steel pipes. This is followed by vulcanization at a controlled temperature to achieve the desired hardness and bonding strength. This protective lining helps prevent corrosion and abrasion, extending the lifespan and functionality of the pipe. The rubber lining process generally consists of the following steps.

Rubber lined carbon steel pipes combine the robust strength of carbon steel with the exceptional properties of rubber lining, offering numerous benefits across various industrial applications. These pipes are designed to meet the demands of both harsh environments and high-performance systems, ensuring durability, efficiency, and cost-effectiveness.

The manufacturing of ceramic lined pipes combines the durability of metal with the high wear and corrosion resistance of ceramics, making them ideal for industries such as mining, chemical processing, power generation, and cement production. These pipes are designed to transport abrasive and corrosive materials while offering a longer service life compared to traditional metal pipes. The process of manufacturing ceramic lined pipes involves several detailed steps to ensure the ceramic lining adheres securely to the pipe and performs effectively under extreme conditions. Below is an overview of the typical manufacturing process of ceramic lined pipe.

Ceramic lined pipes are widely used in industries where pipes are exposed to high wear, abrasion, and corrosive environments, such as in mining, chemical processing, power plants, and cement industries. These pipes combine the durability and resistance of ceramics with the structural strength of metal pipes. The production technology of ceramic lined pipes involves several key steps to ensure the integration of high-performance ceramic materials into the metal substrate. Here’s an overview of the common production process.

The production of plastic-coated steel pipes involves several steps that can lead to various defects affecting both the appearance and performance of the final product. These issues can reduce the quality and durability of the pipes if not properly addressed. Below are some common problems encountered during production.

Rubber-lined pipes are commonly used in industries like mining, chemical processing, and water treatment. Non-destructive testing (NDT) is essential for ensuring the integrity of these pipes without causing any damage. Here are some key NDT methods used for rubber-lined pipes.