Dairy SMS Union
What are Dairy SMS Union?
An SMS Union (Swedish Manufacturing Standard Union) is a hygienic pipe connector used in dairy, food, beverage, and pharmaceutical industries. It includes a male part, liner, nut, and gasket to create a leak-proof joint. Designed for easy assembly and superior hygiene, it supports CIP and SIP cleaning systems.
Asiad Steel Industries is a trusted manufacturer, supplier, and exporter of SMS Unions in SS 304 and SS 316L with fine finish, precision threads, and compliance with SMS 1145 standards.
Key Features
Leak-Proof
Jointing
Sanitary
Design
Easy to
Clean
Standards
Compliant
Corrosion
Resistant
Specifications
| Specification Category | Parameter / Feature | Details / Options |
|---|---|---|
| Size Range | Nominal Bore (NB) | ½” to 6” (DN15 – DN150) |
| Metric Sizes | 12 mm to 154 mm (DIN Standard) | |
| Pressure Ratings | Working Pressure | Up to 10 – 40 bar (depending on size & material) |
| Vacuum Rating | Suitable for full vacuum in hygienic applications | |
| Fitting Types | SMS Union Components | Liner, Nut, Male Part, Gasket (EPDM, NBR, Silicone, PTFE) |
| Variants | Weld End, Threaded End, Hose Tail End | |
| Material Options | Stainless Steel | SS 304, SS 304L, SS 316, SS 316L (as per AISI & DIN) |
| Gasket Materials | EPDM, NBR, Silicone, PTFE (FDA approved) | |
| Other Materials | Customized options available for special applications | |
| Standards & Certifications | Hygienic Standards | SMS 1145, DIN, ISO, 3A, IDF, BS |
| Material Standards | ASTM A182 (Forged SS), ASTM A276 (Bars), ASTM A240 (Plates) | |
| Certifications | ISO 9001, FDA Approved, CE, 3A Sanitary, PED 2014/68/EU | |
| Design Features | Surface Finish | Polished ID ≤ Ra 0.8 μm, OD ≤ Ra 1.6 μm (for hygienic use) |
| End Connections | Welded, Threaded, Hose Shank | |
| Gasket Position | Interchangeable gasket placement for leak-free seal | |
| Assembly | Easy to dismantle & clean, suitable for CIP & SIP processes | |
| Coating & Surface Finish | Surface Treatment | Electro-polished, Pickled & Passivated |
| Optional Finishes | High gloss mirror finish for dairy & pharma applications | |
| Testing & Inspection | Pressure Testing | Hydrostatic & Pneumatic (as per SMS standards) |
| Non-Destructive Testing | Dye Penetrant (DPT), PMI (Positive Material Identification) | |
| Hygienic Testing | Surface roughness check, CIP/SIP validation | |
| Destructive Testing | Tensile & Hardness test on request |
Dimensions
| Size (DN) | Tube OD (mm) | Nut Hex (mm) | Nut Thickness (mm) | Male Part Length (mm) | Liner Length (mm) | Gasket Thickness (mm) |
|---|---|---|---|---|---|---|
| DN10 | 12 | 36 | 15 | 19 | 18 | 3.0 |
| DN15 | 18 | 41 | 16 | 19 | 18 | 3.0 |
| DN20 | 22 | 46 | 18 | 20 | 19 | 3.0 |
| DN25 | 28 | 55 | 20 | 22 | 21 | 3.0 |
| DN32 | 34 | 65 | 22 | 24 | 22 | 3.0 |
| DN40 | 40 | 70 | 24 | 26 | 24 | 3.0 |
| DN50 | 52 | 85 | 27 | 28 | 26 | 3.0 |
| DN65 | 70 | 100 | 30 | 30 | 28 | 3.0 |
| DN80 | 85 | 115 | 32 | 32 | 30 | 3.0 |
| DN100 | 104 | 135 | 35 | 35 | 33 | 3.0 |
Mechanical Properties
| Property | Value | Unit / Standard |
|---|---|---|
| Tensile Strength | 500 – 700 | MPa (for SS 304/316 as per ASTM A182/A240) |
| Yield Strength | 190 – 310 | MPa |
| Hardness | ≤ 200 | HB (Brinell) |
| Elongation | ≥ 40 | % (good ductility for hygienic piping) |
| Density | 7.9 – 8.0 | g/cm³ |
| Impact Toughness | ≥ 100 | J (Charpy V-notch, at room temp) |
| Modulus of Elasticity (E) | ~193 – 200 | GPa |
| Fatigue Strength | 240 – 400 | MPa |
| Corrosion Resistance | Excellent (high resistance to food acids, cleaning agents, CIP/SIP) | – |
| Thermal Conductivity | 14 – 16 | W/m·K |
| Coefficient of Thermal Expansion | 16 – 17 ×10⁻⁶ | /°C (between 20–100 °C) |
| Yield Ratio (YS/UTS) | 0.35 – 0.55 | – |
| Poisson’s Ratio | 0.27 – 0.30 | – |
| Brinell Hardness Range | 120 – 200 | HB |
| Surface Finish | ID ≤ Ra 0.8 µm, OD ≤ Ra 1.6 µm (electro-polished / hygienic finish) | SMS / DIN standards |
| Welding Type | Orbital / TIG weld compatible | – |
| Operating Temperature Range | -20 to 200 | °C (depends on gasket material – EPDM, NBR, PTFE, Silicone) |
| Pressure Rating | Up to 10 – 40 bar | As per SMS 1145 Standard |
Chemical Composition
| Element | SS 304 (%) | SS 304L (%) | SS 316 (%) | SS 316L (%) |
|---|---|---|---|---|
| Carbon (C) | ≤ 0.08 | ≤ 0.03 | ≤ 0.08 | ≤ 0.03 |
| Manganese (Mn) | ≤ 2.00 | ≤ 2.00 | ≤ 2.00 | ≤ 2.00 |
| Silicon (Si) | ≤ 1.00 | ≤ 1.00 | ≤ 1.00 | ≤ 1.00 |
| Phosphorus (P) | ≤ 0.045 | ≤ 0.045 | ≤ 0.045 | ≤ 0.045 |
| Sulfur (S) | ≤ 0.030 | ≤ 0.030 | ≤ 0.030 | ≤ 0.030 |
| Chromium (Cr) | 18.0 – 20.0 | 18.0 – 20.0 | 16.0 – 18.0 | 16.0 – 18.0 |
| Nickel (Ni) | 8.0 – 10.5 | 8.0 – 12.0 | 10.0 – 14.0 | 10.0 – 14.0 |
| Molybdenum (Mo) | — | — | 2.0 – 3.0 | 2.0 – 3.0 |
| Iron (Fe) | Balance | Balance | Balance | Balance |
Applications of Dairy SMS Union
Dairy & Milk Processing
Units
Beverage Plants
Pharmaceutical
Food Processing &
Edible Oil Units
Chemical & Enzyme
Production
Dairy R&D and Quality
Testing Labs
Do you have questions?
What is the key difference between SMS and DIN unions?
Are SMS Unions compatible with CIP systems?
What gasket materials are available for dairy SMS unions?
Can SMS unions be customized for high-pressure use?
