Stainless steel decorative pipe is also called stainless steel welded steel pipe, which is called welded pipe for short. Usually, steel or steel strip is welded into steel pipe after being crimped and formed by the unit and mold. The production process of welded steel pipe is simple, the production efficiency is high, there are many varieties and specifications, and the equipment cost is small, but the general strength is lower than that of seamless steel pipe. There are many kinds of stainless steel pipes, but they are mainly used for the following purposes: 1、 Classification of stainless steel pipes 1. Classification by production method: (1) Seamless pipe - cold drawn pipe, extruded pipe, cold rolled pipe. (2) Welded pipe: (a) According to process classification - gas shielded welding pipe, arc welding pipe, resistance welding pipe (high frequency, low frequency). (b) It is divided into straight welded pipe and spiral welded pipe according to the weld. 2. Classification according to section shape: (1) round steel pipe; (2) Rectangular tube. 3. Classification by wall thickness - thin wall steel pipe, thick wall steel pipe 4. Classified by use: (1) Civil pipes are divided into round pipes, rectangular pipes and flower pipes, which are generally used for decoration, construction, structure, etc; (2) Industrial pipe: steel pipe for industrial piping, steel pipe for general piping (drinking water pipe), mechanical structure/fluid delivery pipe, boiler heat exchange pipe, food sanitation pipe, etc. It is generally used in various fields of industry, such as petrochemical, paper, nuclear energy, food, beverage, medicine and other industries with high requirements for fluid medium. 2、 Seamless steel pipe Stainless steel seamless pipe is a kind of long steel with hollow section and no joints around. 1. Manufacturing process and flow of seamless steel pipe: Smelting>ingot>steel rolling>sawing>peeling>piercing>annealing>pickling>ash loading>cold drawing>head cutting>pickling>warehousing 2. Features of seamless steel pipe: It is not difficult to see from the above process flow: first, the thicker the wall thickness of the product, the more economical and practical it will be. The thinner the wall thickness, the higher the processing cost will be; Secondly, the process of the product determines its limitations. Generally, the precision of seamless steel pipe is low: uneven wall thickness, low brightness of the surface inside and outside the pipe, high sizing cost, and there are pits and black spots on the surface inside and outside the pipe, which are difficult to remove; Third, its detection and shaping must be processed offline. Therefore, it has its advantages in high pressure, high strength and mechanical structure materials. 3、 Welded steel pipe 304 stainless steel decorative tube 304 stainless steel decorative tube Welded steel pipe, referred to as welded pipe for short, is a stainless steel pipe welded from steel plate or steel strip after being crimped and formed by the machine set and mold. 1. Steel plate>Splitting>Forming>Fusion welding>Induction bright heat treatment>Internal and external weld bead treatment>Shaping>Sizing>Eddy current testing>Laser diameter measurement>Pickling>Warehousing 2. Features of welded steel pipe: It is not difficult to see from the above process flow: first, the product is produced continuously and online. The thicker the wall thickness, the greater the investment in the unit and welding equipment, and the less economical and practical it is. The thinner the wall, the lower its input-output ratio will be; Secondly, the process of the product determines its advantages and disadvantages. Generally, the welded steel pipe has high precision, uniform wall thickness, high internal and external surface brightness of stainless steel pipe fittings (the steel pipe surface brightness determined by the surface grade of the steel plate), and can be arbitrarily sized. Therefore, it embodies its economy and beauty in the application of high-precision, medium-low pressure fluid. There is chlorine ion in the use environment. Chlorine ions exist widely, such as salt, sweat, sea water, sea breeze, soil, etc. Stainless steel corrodes rapidly in the presence of chloride ions, even surpassing ordinary low-carbon steel. Therefore, there are requirements for the use environment of stainless steel, and it is necessary to wipe it regularly to remove dust and keep it clean and dry. 316 and 317 stainless steels (see below for the properties of 317 stainless steels) are molybdenum containing stainless steels. The molybdenum content in 317 stainless steel is slightly higher than that in 316 stainless steel. Because of the molybdenum in the steel, the overall performance of this steel is better than 310 and 304 stainless steel. Under high temperature conditions, when the concentration of sulfuric acid is lower than 15% and higher than 85%, 316 stainless steel has a wide range of uses. 316 stainless steel also has good chloride corrosion resistance, so it is usually used in marine environment. With the development of social economy, the application of stainless steel pipe has also been more and more popular. It will bring new changes in all fields.