| Material: | Stainless Steel AISI 316L(1.4404) |
| Seal Material: | FDA-compliant Blue HNBR/EPDM, Hardness 85+5 Shore A |
| Thread Range: | M4 to M16 |
| Surface Finish: | Matte finish (Ra < 0.8 µm) Polished finish (Ra < 0.8 μm) |
| Compliance: | Designed to EHEDG, 3-A, and FDA guidelines |
Our hygienic design stainless steel nuts are engineered for applications where cleanliness, corrosion resistance, and contamination prevention are essential. Designed specifically for food processing, dairy, beverage, and pharmaceutical machinery, these nuts provide a secure fastening solution while maintaining a smooth, easy-to-clean surface.
| Part Series | d3 | t min | d1 | h | SR | R | A/F |
|---|---|---|---|---|---|---|---|
| VTN28 | M4 | 6 | 11 | 9.5 | 7 | 25 | 7 |
| VTN28 | M5 | 6 | 12 | 10.5 | 8 | 25 | 8 |
| VTN28 | M6 | 7.5 | 14 | 12.22 | 9 | 25 | 10 |
| VTN28 | M8 | 9.5 | 18 | 14.5 | 11 | 35 | 13 |
| VTN28 | M10 | 12 | 21 | 17.92 | 13 | 50 | 16 |
| VTN28 | M12 | 14.5 | 25 | 21 | 15 | 50 | 18 |
| VTN28 | M14 | 15.5 | 28 | 23.5 | 20 | 70 | 21 |
| VTN28 | M16 | 17 | 32 | 26 | 26 | 70 | 24 |
| Item | Specification |
|---|---|
| Nut body | AISI 316L stainless steel / EN 1.4404 |
| Certification | 3-A certified |
| Surface finish | Matte or polished, Ra < 0.8 µm |
| HNBR sealing ring | Blue, FDA-compliant material, 85 ±5 Shore A, -25 °C to +150 °C |
| EPDM sealing ring | Blue, FDA-compliant material, 85 ±5 Shore A, -40 °C to +120 °C |
FDA compliance applies to the sealing-ring material, not to the complete nut or installed assembly.
Through our discussions with pharmaceutical equipment manufacturers, we have found that elastomer seals are unsuitable for some high-temperature sterilization and cleaning processes. However, these applications may still require sealing at the fastening point.
Hygienic nut with a metal-to-metal seal: This option uses a metal-to-metal sealing design and requires the sealing contact surface to be precisely finished to Ra < 0.8 µm.
Hygienic nut without a seal: This option is available for applications where sealing is not required.
Hygienic stainless steel nuts are widely used in:
What is the difference between HNBR and EPDM seals?
HNBR: High mechanical strength and good resistance to oil, heat, wear, ozone, and ageing. Well suited to demanding sealing applications involving oils and lubricants.
EPDM: Excellent resistance to weathering, ozone, hot water, and steam, with good flexibility at low temperatures. Generally unsuitable for petroleum-based oils and fuels.
Based on our market observations, HNBR seals are common in food-processing equipment and EPDM seals in pharmaceutical equipment. For other applications, contact us to confirm the suitable material.