Food-Grade Seamless Duplex Stainless Steel Tube Surface Drawing Process

With the advancement of the times and people's requirements for quality of life, stainless steel is not only widely used in the food and beverage manufacturing and processing industries for manufacturing, bulk storage and transportation, preparation and display applications, but also widely used in the modern construction industry.

Food-grade stainless steel is the reliable material choice for the food industry.  Stainless steel not only can withstand harsh temperatures, but its oxidation protection layer can also prevent rust and prevent food contamination. One of the important characteristics of food-grade stainless steel is that it does not contain hazardous chemicals that may transfer to food.

Food-grade Pipelines Requirements:

1. Material requirements: It is usually made of stainless steel materials such as 304 and 306 that are corrosion-resistant, non-toxic, and do not contain dissolved substances to ensure the purity and hygiene of the product. 304 and 316 stainless steel pipe are common pipe choices because they are relatively low cost, corrosion resistant, and easy to clean.

2. Processing technology requirements: For the processing technology of sanitary pipelines, special machinery and equipment, and processes are required to ensure that the smoothness of the internal surface of the pipeline meets the requirements.

3. Interface connection requirements: Sanitary flange connections, sanitary clamping connections, sanitary threaded connections, etc. are usually used to ensure the sealing and hygiene of the connections.

4. Cleanliness requirements: The cleanliness requirements of sanitary pipelines are very high, and special cleaning methods and equipment are required to ensure the complete removal of pollutants inside the pipelines.

Surface Finish：

Surface finish is 20 μ-in Ra (0.5 μm) ID maximum, 30 μ-in Ra (0.8 μm) OD maximum surface roughness measured per ASME/ANSI B46.1 with the profilometer reading at 90 degrees to the major polishing pattern. All tubing is printed with size, gauge, alloy, ASTM and ASME specifications, heat number, and date of manufacturing for full traceability.

Testing and packaging：

To ensure strict compliance with ASTM A270 and 3A, all sanitary pipe undergoes extensive reverse bend, reverse flattening, flange, and eddy current testing. Upon successful completion of testing, the tubes are sealed with airtight end caps and individually packaged in high-quality polyethylene sleeves. The tubes are then packed in wooden boxes.