DIN6927 Stainless Steel Carbon Steel Nylon Flange Nut

  This product is a hexagon flange nut manufactured to DIN 6927 , featuring an integrated flange that replaces the need for a separate flat washer. Available in both carbon steel (property class 8 or 10) and stainless steel (A2-304 or A4-316) variants, it incorporates a non-metallic nylon insert (prevailing torque element) within the threaded portion. This design provides resistance to loosening under vibration and is widely used in automotive, machinery, and structural applications requiring secure locking without additional components .

What are the material property classes and mechanical requirements for carbon steel versus stainless steel versions?

For carbon steel versions, property classes 8 and 10 are standard, with class 8 nuts requiring a proof load stress of 800 MPa suitable for grade 8.8 bolts, and class 10 requiring 1000 MPa for grade 10.9 bolts . Stainless steel versions conform to A2-70 (304 series, 700 MPa tensile) or A4-80 (316 series, 800 MPa tensile) as specified in ISO 3506 . The nylon insert must withstand prevailing torque tests without cracking or losing locking capability after multiple installations .

How does the nylon insert achieve prevailing torque, and what are its performance limits?

The nylon insert is permanently bonded into the nut's threaded portion. When engaged with a mating bolt, the insert is compressed, creating frictional resistance that prevents loosening from vibration . The prevailing torque must meet specified values at first installation and after 5 or 15 re-uses depending on the standard . Operating temperature range for the nylon element is typically -50°C to +120°C , beyond which the locking performance may degrade .

What are the dimensional and functional advantages of the integrated flange design?

The integrated flange, with a bearing surface diameter approximately 1.8 times the thread diameter , distributes clamping load over a larger area compared to standard hex nuts, reducing the risk of surface indentation . The flange also provides a smooth, chamfered bearing surface that minimizes damage to painted or coated substrates . This design eliminates the need for a separate washer, reducing assembly time and component inventory while maintaining consistent clamp force distribution .