How to choose the best quality stainless steel dairy fitting?

Shuangzhan machinery is an international manufacturer and supplier of premium components including stainless steel fittings, valves, sanitary gaskets, pumps, manifolds, custom fabrication and filters for hygienic processing applications in the dairy, food, beverage, pharmaceutical, cosmetics, and other hygienic industries. 

Stainless steel dairy fittings are our main products, for hygiene reasons, all parts of dairy equipment are made of stainless steel. AISI304 and AISI316 are main grades used. 

Specifications for European and USA steel grades are:

USA           AISI 304           AISI 316           AISI 316L
Europe      EN 1.4301        EN 1.4401       EN 1.4404

Stainless steel tubing, sanitary welded fittings, clamp fittings, unions, union fittings, filters, gaskets, valves, sight glasses and pumps are components commonly used in dairy farming or factory. Hereby we introduce pipe system and connection, and next we will introduce mix-proof valve, shut-off valve, control valve and sample valve.

The pipe system

Sanitary tubing and other components assemblied a pipe system, and the product flows between the components of the plant. There are also pipe systems for other media such as water, steam, cleaning solutions, coolant and compressed air. A waste-water system to the drain is also necessary. All these systems are basically built up in the same way. The difference is in the materials used, the design of the components and the sizes of the pipes.

All components in contact with the product are made of stainless steel, AISI316 often. Various materials are used in the other systems, e.g. cast iron, steel, copper and aluminium. Plastic is used for water and air lines, and ceramic for drainage and sewage pipes.

These following fittings types are included in the product pipe system:

• tubings, elbows, tees, reducers and unions

• sight glasses, instrument bends, filters etc.

• control valves, shut-off valves etc for stopping,flow control and directing the flow

• pressure relief/vacuum valve

• pipe supports and clamps

Connection

Welded parts are permanent where disconnection is required, Europe often use a threaded union with a male end, a liner, a gasket and a nut, North Amercian, e.g. Canada, USA and Mexcio often use a clamped union with a gasket, all gaskets available silcion, buna, viton, EPDM, PTFE, food grade absulotely.

The union permits disconnection without disturbing other pipe-work. This type of joint is therefore used to connect process equipment, instruments, etc. that need to be removed for cleaning, repair or replacement.  Different countries have different union standards. There are SMS (Swedish Dairy Standard), DIN (German), BS (British), IDF, 3A and ISO clamps (these two widely used in the USA). Bends, tees and similar fittings are available for welding, union and clamps, so there are clamp bends, clamp tees, union bend and tee with male, liner or nut ends.

All unions must be tightened firmly to prevent liquid from leaking out or air from being sucked into the system and causing problems in downstream parts of the process.

Sight glass is a window when user wants to check of the product is required. Instrument tee or bend is for gauges or sensors often, they are maybe short equal or reducing.