Alwin Höfert KG products

Round cord rings are utilized when appropriate O-ring shapes are unavailable, and the production of custom tooling is not cost-effective due to low volume requirements. Unlike molded O-rings, these rings are formed from extruded cord material which can be cut to any specific inner diameter and assembled via splicing or butt vulcanization to meet DIN 7715 standards. Over recent years, vulcanization has become preferred due to its superior physical properties compared to adhesive bonding, albeit the joints possess lesser mechanical strength compared to the original extruded cord. Therefore, these types of rings are not suitable for dynamic sealing, vacuum, or gaseous media applications. The dimensional deviations for cord diameter adhere to DIN 7715 Part 3, Class E2, with circumferential tolerances of ±0.8 percent. Standard O-ring tolerances do not apply. Since 1963, Alwin Höfert KG has been producing quality O-rings and special seals, providing German-made excellence to its clientele.