High-pressure alloy steel pipes are pipes made from alloy steel that are specifically designed to withstand high-pressure environments in various industrial applications. Alloy steel is a type of steel that contains additional alloying elements (besides carbon) to enhance its mechanical properties, such as strength, hardness, and resistance to wear and corrosion.

API 5L is a line pipe specification that defines requirements for the manufacture and transportation of oil and natural gas.

Preventing corrosion of oil casing is crucial to ensure the integrity and longevity of oil wells.

Surface treatment of stainless steel pipes is to improve its corrosion resistance, aesthetics and other properties.

OCTG (Oil Country Tubular Goods) casing refers to a type of steel pipe used in the petroleum and natural gas industries, particularly for drilling and producing wells.

The choice between 304 stainless steel and 316 stainless steel for a pipe depends on the specific requirements of the application, as each alloy has its own set of characteristics and advantages.