TOBI® Drive-System
The high-performance screw drive concept
Applications Engineer
With the HardTip process, the forming zone of the thread point of a screw is additionally inductive-hardened after previous hardening and tempering or case hardening. Thus, materials which have too high a strength for conventionally hardened screws can also be fastened in a self-tapping way. EJOT® HardTip screws are used if case-hardened fastening elements are not permitted or conventionally hardened screws would fail because the screw-in material is too strong.
Thread geometries EJOT® HardTip:
- Spiralform®
- SHEETtracs®
Further thread geometries upon request.
With the patented "anti cross-threading" points MAThread® and MATpoint® for metric standard threads according to ISO 965-2, EJOT is licensee of MAThread Inc., Whitmore Lake, MI, U.S.A. "Cross threading" is caused by the screw being applied at an angle to the female thread. In the worst case, a new thread is formed or the nut or screw thread is damaged. This ultimately leads to the fact that the screw can not be fastened and the connection fails. The MAThread®/MATpoint® design prevents this "cross threading" and enables shorter assembly times. It reduces or eliminates outages with all negative consequences such as downtimes, reworks, scrap and service effort.
Every screw connection loses clamp load after assembly due to subsidence. If the clamp load falls below a critical level, the connection fails, for example through loosening, separation or a loss of electric contacting. These failures can be prevented by increasing the elasticity in the screw connection, for example with the integration of spring elements into the screw connection. The innovative EJOT® SpringHead geometry realises this resilient feature and reliably compensates for subsidences without additional, conventional spring elements. The spring integrated in the screw head enables a better clamp load retention under dynamic and thermal stress as well as a permanent electrical contacting.
Thread geometries EJOT® SpringHead:
- DELTA PT®
- ALtracs® Plus
- metric screws
Further thread geometries upon request.
1. EJOT CONLOK® - Electric contact
2. EJOT VIBRALOK® - Thread lock
3. Locking serration Thread lock
4. Friction serration Higher Stripping Torque TS
5. EJOT CONLOK® - Ring cutting edge
The EJOT CONLOK® under-head serrations show a discontinuous cup point with a transfer radius starting at the fastener shank. The number of tooth is variable, according to customer request or application. Only the narrowing form is specified.
Advantage:
- Electrical contact between components and fasteners
- Surface coatings up to a thickness of 70µ (powder coating) can be scratched open
- Increased installation and loosening torques due to free design of the serration tooth
EJOT VIBRALOK® has been developed as a thread lock for vibration exposed screw heads connecting to metallic surfaces. Independent expert analysis testify the outstanding properties.
Advantage:
- Increasing the loosening torques
- Prevents loosening under vibration stress
With the combination of two different materials, the EJOT duoHARDtip® screw offers both - a conventionally hardened shaft and an advanced high-strength point. This offers the possibility of direct fastening in advanced high-strength steel materials, setting new standards in terms of the possible application range. The duoHARDtip® complies with highest corrosion requirements, furthermore it reliably prevents hydrogen-induced embrittlement. This is especially crucial to those applications where case-hardened screws are not permitted.
Thread geometries of EJOT duoHARDtip®:
- Spiralform®
- SHEETtracs®
Further thread geometries upon request.