Why Choose OMSS Dairy Union
- Verified 304/ 304L/ 316L stainless steel material with MTR report through spectrometers
- Orders from 20 nations,15 years of experience in manufacturing dairy unions
- Advanced equipment from Mazak CNC Japan, high-tech machinery for precision
- Fine interior finish reaching Ra ≤ 0.8 μm, undergoing strict inspections
- Highly customised service, including OEM marking and surface polishing
- Consistent delivery cycles ensure your worry-free production schedules
OMSS: Your Reliable Dairy Union Supplier
OMSS specializes in manufacturing stainless steel fluid components. We utilize premium stainless steel materials and advanced manufacturing processes to ensure our products provide exceptional sealing performance and long-lasting durability.
OMSS dairy unions are finely polished on both the interior and exterior surfaces. The smooth surface ensures your product liquids do not accumulate in the dead corners.
OMSS dairy unions meet the common international hygienic standard, including 3A, ISO, DIN, etc. They are widely used in the dairy industry, which requires fluid components. If you need dairy unions for your pipeline systems, contact us and get your one-stop dairy union solution.
Types of OMSS Dairy Union

Precise in sizes, designed for quick assembly, and using durable materials. Highly compatible with DIN components, fits modular piping systems.

ISO- certified pipe fittings, with extraordinary pressure resistance and sealing performance. Supporting connection with pipes of various materials and adding components.

Compliance with 3A sanitary standards and eliminating bacteria growth ensures the safety, quality, and flavor of your products.

Easy installation and secured sealing, adapts thermal expansion compensation and frequent adjustments, promotes the stability of your pipe system.
Features of OMSS Dairy Union

OMSS dairy unions are made of 304, 304L, or 316L stainless steel. The high-quality material makes the dairy unions with exceptional corrosion resistance.

OMSS dairy unions are resilient in high-temperature environments. The gaskets maintain excellent sealing performance in heat and steam cleaning.

OMSS dairy unions remain robust in high-pressure conditions. They maintain leakage-proof and resist bending under pressure and vibration.

OMSS dairy unions are finely polished to make the surface easy to clean. The smooth interior surface also makes the flow pressure consistent.

OMSS dairy unions are easy to install with common tools. And the nut is removable for routine maintenance.

Stainless steel is a 100% recycle material, and it leaks no poisonous liquid to the water during production.
High Hygienic Standard
The dairy industry has an extensive hygienic standard, and OMSS dairy unions help maintain your product integrity and sanitation throughout pasteurisation, homogenization, and storage stages with their leak-proof connections.
OMSS dairy unions are finely polished on both inside and outside surfaces. The smooth surface reduces the sanitary dead corners for cleaning. The thermal resistance of the material allows OMSS dairy unions process CIP (cleaning-in-place) procedures to maintain hygienic conditions.


Fitting in Different Pipe Systems
OMSS has dairy unions of the most commonly used dimensional standards in the international market, including DIN standard, SMS standard, ISO standard, 3A standard, and RTJ standard.
OMSS also supports the customization of dairy unions. You can search the product handbook and the technical documentation first, and contact us to select the best-fit dairy unions for your pipe systems.
Durable for Longevity
Dairy production requires a wide temperature variation during pasteurisation processes that milk is heated for times. OMSS dairy union is made of 304, 304L, and 316L standard stainless steel. The stainless steel is durable for resistance to corrosion, temperature fluctuations, and high-pressure environments. These properties make OMSS dairy unions resistant to temperature variations and corrosion from the natural acids in milk over a long time.

Applications of Dairy Union

Liquid milk processing includes handling, pasteurization, homogenization, storage, and packaging of fresh milk products. OMSS dairy unions are used to connect the sanitary pipe systems and the manufacturing equipment.
In typical liquid milk factories, the fresh milk products are transported from storage tanks to UHT sterilization systems through pipelines. OMSS dairy unions are installed in crucial positions such as plate heat exchangers, homogenizers, pumps, valves, and storage tanks. Their thread structure allows operators to check and adjust the pipelines quickly.

Yogurt processing includes pasteurizing, cooling, inoculating with bacterial cultures, fermenting, mixing, and filling. In these procedures, OMSS dairy unions play a key role in enhancing the pipelines’ stability and flexibility.
The active bacterial cultures contained in the fermented products require strict hygienic conditions. OMSS dairy unions used stainless steel and corrosion-resistant gasket materials to adapt to frequent CIP procedures. The smooth interior surface can reduce bacterial growth to the lowest level.

Milk powder processing includes milk concentration, evaporation, spray drying, cooling, and packaging. In these procedures, OMSS dairy unions are utilized to connect the pipelines that transport milk and concentrated dairy products.
In the feed lines leading to spray dryers, concentrated milk is sent to spray drying towers through pipelines. OMSS dairy unions secure your pipelines of leakage-proof and hygienic connections and prevent contamination during the drying process. Their adjustable design also reduces downtime during maintenance operations.

Cheese processing includes milk preparation, coagulation, curd cutting, whey separation, pressing, salting, and aging. In these processes, the pipe system transports milk, whey, brine solutions, and cleaning fluids. OMSS dairy unions are widely applied for their reliable and hygienic connections.
The brine tanks in the cheese salting process require corrosion-resistant pipe systems. 316L stainless steel is resilient against salty water conditions and detergents, and provides excellent sealing performance. Their smooth interior surfaces and sanitary gaskets prevent contamination and bacterial growth.

Ice cream processing requires accurate temperature control, sanitary ingredient processing, and flexible pipe systems.OMSS dairy unions are utilized in pipe systems transporting milk, cream, syrup, spices, and stabilizers.
The ice cream mixture is pasteurized and homogenized before sent into the agent tanks. The facilities are automatically cleaned with CIP systems, and using OMSS dairy unions to connect the pasteurizers, homogenizers, pumps, and storage tanks makes routine maintenance and cleaning simple.

Liquid whey is a by-product of cheese manufacturing. Producing whey into high-value ingredients of nutrition products requires advanced filtration, concentration, and drying technologies supported by hygienic piping systems. OMSS dairy unions are applied to connect the pipelines of filtration and concentration systems.
The systems (such as Ultrafiltration (UF), microfiltration (MF), and reverse osmosis (RO) systems) rely on complex pipe networks. OMSS dairy unions offer a great capacity for adjustment and reform of the pipelines.
- Certificate of Compliance
Customer Reviews
No, they can’t. DIN and SMS dairy unions are different in the thread type, sealing face structure, and dimensional standard. In the dairy industry, pipeline systems have strict sanitary demands. Using unmatchable dairy unions can influence the sealing performance and contamination risks.
If you need to connect DIN and SMS systems, adapters are required. These components can ensure the sealing and secure hygiene conditions.
Most modern dairy factories utilize CIP systems. During it works, the alkaline detergents, acidic rinses, and hot water circulate in the pipe system and remove the fat, protein, and mineral deposits by altering the water temperature and flow speed.
Besides CIP, routine inspection by operators is recommended. The operators should loosen the nuts, separate the ferrules, and remove the gasket to check if there is cratches or residue, and clean with food-grade detergents and soft brushes.
Yes, they can. OMSS dairy unions are ideal for automatic product lines.
Automatic production systems use stainless steel piping to transport liquids such as milk, cream, and yogurt, and dairy unions are the key connecting components in these systems.
The engineers in automatic factories form modular systems by quickly connecting pumps, valves, heat exchangers, and tanks with dairy unions without welding.
OMSS dairy unions undergo strict inspections during manufacturing. Here are the main inspections.
- Material inspection: OMSS uses spectrometers to ensure the 304, 304L, and 316L stainless steel meet the standards.
- Dimensional inspection: Including the dimensions of the thread, nut, and ferrules. To ensure they meet the standards of DIN, SMS, ISO, 3A, and RTJ.
- Surface finish inspection: OMSS measures the surface roughness to ensure the interior surface is smooth for hygienic purposes.
Yes, they can. OMSS dairy unions are widely used in the liquid food industry.
During the production of beverages such as bottled water, sparkling water, juice, beer, and wine, OMSS DIN unions are widely applied. They provide stable sealing performance to prevent gas leakage and ensure the sparkling beverage system under consistent pressure conditions.
In the process of brewing, high and low temperatures are required. Stainless steel dairy unions are resistant to temperatures and acidic beverages.
OMSS dairy unions can be installed in various directions according to the pipe system and the direction of liquid flow. They can be assembled vertically, horizontally, and obliquely.
Horizontal installations stabilize the liquid flow and simplify the cleaning process. They are easy to adjust and disassemble.
Vertical installations are common in connections between different layers of the transportation system, such as storage tanks and filling equipment.
Yes, they can. OMSS dairy unions can deal with the common viscous liquids in the food industry. The examples of viscous liquids include cream, yogurt, syrup, sauce, honey, and concentrated milk. The OMSS dairy unions have very few seams, and the surface is finely polished. These features ensure the flow is stable when transporting viscous liquids.
Yes, they do. OMSS dairy unions are highly compatible with modular pipeline systems. One of the key advantages of the OMSS dairy union is its quick assembly and disassembly without welding, which allows for easy reforming of the pipe system.
What is a Dairy Union?
A dairy union is a sanitary connecting component for stainless steel pipes. It is widely applied in the dairy, food, and pharmaceutical industries.
A dairy union has three parts: a union nut, two ferrules (including a male part and a liner), and a gasket. When you screw the nut tightly, the liners compress the gasket and create a reliable and leakage-proof connection.
The common materials of the main body are 304, 304L, and 316L stainless steel and meet the DIN, SMS, ISO, 3A, and RTJ standards.
Dairy Union Gasket Types and Materials
EPDM
EPDM is one of the most common materials for sealing gaskets. It resists high temperature, steam, and chemical cleaners, making it optimal for dairy production factories equipped with the CIP system.
Silicone
Silicone rubber provides high flexibility and resists a wide range of temperatures, which adapts to the food and pharmaceutical industries with high purity demands.
PTFE
PTFE has corrosion resistance to chemicals, and is suitable for cleaning with strong detergents and environments exposed to special chemical ingredients.
NBR
NBR is ideal for products with oil and fat, but it cannot resist high temperatures.
Thread Types for Dairy Unions
| Standard | Thread Type | Typical Application | Key Characteristics | Common Regions of Use |
| DIN (DIN 11851) | Metric thread | Dairy processing, food and beverage production, hygienic piping systems | Uses a union nut and gasket sealing system. Provides a strong mechanical connection and reliable sealing. Compatible with European sanitary pipeline equipment. | Europe, Asia, and international dairy plants |
| SMS (SMS 1145) | Rounded sanitary thread | Dairy pipelines, milk processing equipment, beverage production lines | Similar structure to DIN but with a slightly different thread profile and sealing surface. Known for smooth internal design and hygienic performance. | Scandinavia, Europe, global dairy facilities |
| ISO (ISO 2853) | Metric sanitary thread | International sanitary pipeline systems, food processing and beverage production | Designed for international compatibility. Provides standardized dimensions and hygienic sealing suitable for global processing plants. | Worldwide |
| 3A (3-A Sanitary Standard) | Sanitary thread or clamp connection | Dairy processing, pharmaceutical, and food production lines | Designed according to strict hygienic standards. Ensures easy cleaning and high sanitary performance. | United States, North America |
| RTJ (Ring Type Joint) | Precision-machined thread with a metal ring seal | High-pressure industrial pipelines, specialized processing systems | Uses a metal ring gasket to create a high-pressure seal between precision-machined grooves. | Global industrial sectors |
International Standards System of Dairy Union
| Comparison of International Standards | |||
| Standard | Country/Region | Main Application | Key Features |
| DIN | Germany / Europe | Dairy, food processing equipment and piping | Widely used in Europe, precise engineering standards |
| SMS | Sweden / Scandinavia | Dairy and food industry pipe fittings | Simple structure, reliable sealing |
| ISO | International | Global industrial and dairy standards | Internationally recognized quality and safety standards |
| RJT | United Kingdom | Dairy and sanitary pipeline systems | Hygienic design, easy cleaning |
| 3A | United States | Dairy, food, and pharmaceutical equipment | Strict hygienic requirements, sanitary design |
Comparison Between Dairy Union and Other Connection Methods
Difference Between Dairy Union and Tri-Clamp
Dairy Union has better vibration resistance and connecting stability in long-term connections. And Tri-clamp has a simpler structure. It has weaker mechanical strength and more flexibility for adjustments. Both of them offer you high hygienic conditions.
Difference Between Dairy Union and Welded Connections
A welded connection is permanent. It has better sealing performance, but cannot be disassembled without damaging the material.
A dairy union is flexible for your modular production. It can be removed for cleaning and reforming the pipe system.
Difference Between Dairy Union and Flange Connections
The flange connection is larger and heavier, and needs several nuts to fix. It provides better sealing performance for your pipe system and has higher pressure capacity.
The dairy union has a simple structure compared to a flange connection. It has better hygienic properties and is smaller.
Benefits of Detachable Structure
A detachable structure is a key feature of many sanitary pipe connections. The advantage is not only the connecting method, but also in the aspect of long-term operation and maintenance. When a part of your pipe system is worn and corroded, it can be replaced by disassembling the connection itself without cutting pipes. Thus, it lowers the downtime and maintenance cost.
















