Standards regulate sanitary tubing uses. Over the years, these standards have evolved as the tubing and fittings have been used in real-life applications. Today, standards vary, which can leave people confused. The following guide provides an overview of common sanity piping standards and their applications.
Materials
Most sanitary piping uses stainless steel thanks to its low cost and durability. Stainless steel is also used for sanitary tubing accessories because it resists corrosion better than other materials. This steel comes in various grades, with higher grades resisting corrosion more effectively. The price of the steel increases with the grade.
Surface Finish
Surface finishes for stainless steel components confuse many because various industries use different reference scales. Most people look at surface roughness scales, with the two most commonly used scales being Ra and grit. Ra refers to the roughness average outlined in ANSI/ASME standard B461.1985. A mirror finish has an Ra of 4. However, the dairy and food industry considers grit rather than Ra. Grit refers to the amount of abrasive grains found in a given area. Higher grit numbers have smoother finishes.
Manufacturers may use electro-polishing to finish a product and provide a smooth surface. People can identify items that have undergone this process because they have the initials EP, and the finish is superior and looks like a mirror. All product piping undergoes interior polishing to prevent soils and microorganisms from adhering to the surface. The finish or the cleaning procedure determines exterior finishes. Insulated surfaces are typically unpolished, while mill-finished piping is appropriate for applications where soil residues and microbial levels are of little concern.
Sanitary Tubing
Seamless stainless steel tubing is widely accepted for metal fabrication, making standardization easier. People can quickly determine which tubing best meets their needs. Sanitary tubing is identified by its exterior diameter and gauge, with 16-gage tubing being the most common. This tubing is made per ASTM A270.
Pipe Fittings
Pipe fittings must also be considered when selecting tubing. Many joint styles and sealing techniques are used to create these products, and industry, manufacturer, or user group often categorizes fitting types. Adapters help connect different fittings or connect fittings to non-sanitary piping. Each component must be carefully selected, particularly when mating a new pipe to existing equipment.
Clamp and bevel seat fittings are commonly used for systems that must be disassembled regularly. Permanent pipe systems allow for the use of butt-weld fittings. The 3-A Sanitary Standards Institute has established hygienic design and sanitation standards for fittings and pipelines. Health inspectors accept fittings that bear the 3-A symbol. Sanitary joints may use gaskets made using food-grade rubber or plastic.
Pipeline Installation
Pipeline materials are only as good as the installation. To prevent issues, professionals should install stainless steel piping. They use orbital welding techniques and inert gas before polishing the piping. Fixing installation mistakes is costly, so this job should be left to the professionals.
Most food processing operations would halt without sanitary piping systems. A manufacturer can never discount the importance of these components and systems. When the piping system is appropriately designed, constructed, and installed, the manufacturer has little to worry about. The system won’t need much attention and will help maintain product quality. As many factors go into creating and installing this system, the job is best left to professionals to reduce the risk of future problems.
