Common steel pipe products

Conventional steel pipes mainly include the following types:

By manufacturing method:

Seamless pipes: the pipe surface has no seams.
Welded pipes: pipes made from steel sheet or strip by twisting and welding.
By material:

Carbon pipes: pipes in which carbon is the main alloying element.
Alloy pipes: pipes in which one or more alloying elements are added to carbon steel to improve performance.
Stainless steel pipes: pipes that are corrosion resistant, with chromium and nickel as the main alloying elements.
By pipe end connection method:

Pipes without threads: pipes without threads at the ends, usually used for welded or flanged connections.
Threaded pipes: pipes with threads at the ends, convenient for threaded connections.
By surface coating characteristics:

Black pipes: the surface is not coated, the metallic color of the pipe itself is preserved.
Coated pipes: the surface of the pipes is treated with a coating to improve corrosion resistance or other characteristics, e.g., galvanized pipes, plastic-coated pipes, etc.
By cross-sectional shape:

Round pipes: pipes with a round cross-section, the most common pipe shape.
Non-standard pipes: pipes with a non-round cross-section, such as square, rectangular, oval, etc., are used in special cases.

-What are the national standards for galvanized pipes? What are they usually like?

The national standard for galvanized pipes is not a single indicator, but depends on the type of pipes and their purpose. Below is a detailed description of the national standard for galvanized pipes:

I. Types of galvanized pipes

Cold-rolled seamless galvanized pipes: these pipes undergo a cold rolling process, have high precision and a smooth surface, and are often used in cases where high requirements are placed on dimensions and surface quality.
Hot-rolled seamless galvanized pipes: produced by hot rolling, they have good mechanical properties and a wide range of sizes, suitable for various structures.
Seamless galvanized pipes for low and medium pressure boilers: specially designed for low and medium pressure boiler systems, they have high thermal and corrosion resistance.
Welded galvanized pipes: connected by welding, they are low-cost and high-performance, widely used in water supply, gas supply, and other piping systems.
Spiral welded galvanized pipes: manufactured using spiral welding, suitable for large diameter pipelines, often used for transporting oil, gas, and other substances over long distances.
Galvanized pipes for electrical wiring: specially designed for electrical wiring and cables, characterized by thin walls and light weight, used to protect electrical wiring from external damage.
II. Wall thickness standards

The wall thickness of galvanized pipes varies according to national standards and depends mainly on the type and purpose of the steel pipes.
Steel pipes of the same diameter may have different wall thicknesses depending on the type. For example, steel pipes for electrical wiring are usually referred to as thin-walled, while other types of steel pipes are referred to as thick-walled.
Thickened steel pipes are pipes whose wall thickness exceeds the thickness specified by national standards. The specific wall thickness value is determined based on the pipe diameter and design requirements.
III. Market Status

Currently, in the galvanized pipe market, including large state-owned factories, pipe manufacturers have negative wall thickness deviations, i.e., the actual wall thickness is less than that specified by national standards.
Thus, state standards for galvanized pipes cover several aspects, including pipe type, wall thickness, and the current market situation. When selecting galvanized pipes, it is recommended to choose products that comply with state standards and are reliable in terms of quality, depending on the specific conditions of use and requirements.