Direct screw-fittings

EJOT ALtracs® Plus

Optimize processes and reduce costs with EJOT ALtracs® Plus self-tapping screws.

For more safety

Optimally fasten components that are stressed: With the EJOT ALtracs® Plus screw for light metals

Thinner, lighter, better fastened – it’s not surprising that self-tapping screws are gaining more and more significance in the market. EJOT ALtracs® plus screws can be used wherever light metals must be quickly and reliably fastened. Their properties allow the work steps of drilling, thread-cutting, and cleaning to be avoided, thus making the screw particularly economical.

Plus factors

EJOT ALtracs® Plus advantages

Suitable for lightweight construction

The optimized thread geometry of the EJOT ALtracs® Plus enables the use of smaller and shorter screw dimensions, yet its high strength remains the same.
Vibration-resistant

Even without additional safety elements the connection is extremely vibration-resistant.
Metric compatibility

Multiple repeat fastenings are possible. In addition, if there is a need for service, the EJOT ALtracs® Plus can be replaced by a metric screw.
High screw safety

Minimal loss of preload force: The screw holds even under high dynamic and thermal load.
Reliable

High installation safety: Thanks to low installation torque, the EJOT ALtracs® Plus is particularly well-suited for automatic fastenings.

Method and principle

Safe direct fastening for thin-walled light metal components

EJOT ALtracs® Plus is a direct fastener that joins components securely and enduringly without an additional thread-cutting process. Since work steps that were previously necessary – drilling, thread-cutting, cleaning are avoided – you can perform the entire assembly process with greater cost-efficiency. Along with optimizing tool procurement, stock-keeping and cycle times, savings of up to 30 percent can be realized.

Illustration of the work steps for setting screws — **EJOT ALtracs® Plus screw** work steps compared with the work steps of a conventional screw.

Functionality of the EJOT ALtracs® Plus

The EJOT ALtracs® Plus in detail

Optimized thread geometry
With a screw flank angle of 33° instead of 60°, the EJOT ALtracs® Plus achieves a higher connection strength because the load capacity of the nut thread is geometrically increased. The smaller displacement volume of the 33° flank causes lower insertion torques.

Low material displacement due to small 33° flank

Larger nut thread tooth

Greater load capacity of each individual EJOT ALtracs® Plus thread turn

Shorter length of thread engagement is possible
Thread structure
A flat load flank of 22° causes a large axial force component (preload force) and low radial tension. The 11° rear flank prevents premature failure of the thread flank at high preload forces. The tooth root reinforcement provides a stable connection of the thread flank to the screw core.

Small load flank of 22° generates high preload force

Additional stability due to 11° rear flank that absorbs high preload force

Stable connection of the 33° thread flank to the screw core through tooth root reinforcement
In comparison: A 60° thread
Thread of a screw with 60° flank angle in detail

Smaller nut thread tooth than EJOT ALtracs® Plus

Reduced load capacity of each individual thread turn

Greater length of thread engagement necessary
Metric compatibility

The EJOT ALtracs® Plus at assembly forms a thread that you can also reuse for metric screws. If service or repair should be necessary, you can install conventional screws with no problems.
Circular thread geometry
The large flank coverage results in higher extraction forces. The circular contact surfaces in the thread enable higher self-locking and thus an increased screw-locking function. Since more thread flanks are in use, the acceptance of bore tolerances is higher.

Maximum flank coverage

Larger bore tolerances are possible
Improved thread-forming zone
Non-circular short point

Easy setting of the screw

Safe penetration into the material

Safe penetration into any cast skin that may be present

Load capacity of the screw connection

The EJOT ALtracs® Plus cuts a play-free nut thread in light metal. Together with the geometrically reinforced nut thread tooth and the strain hardening effect when forming the thread turns, it produces a screw connection with high resiliency – even under thermal load.
Moreover, the formed EJOT ALtracs® Plus thread attains high dynamic safety due to the effective clamping torque. Additional measures are not necessary, including polyamide coating, micro-encapsulation or underhead profiling.

EJOT ALtracs® Plus compared with metric screws

Relative to strength class 8.8

Higher preload forces
Thus, it may be possible to use smaller screw dimensions
Comparable long-term behaviour
Higher break loose torques
Greater axial extraction forces

Relative to property class 10.9

Comparable preload forces
Comparable long-term behaviour
Higher loosening torques
Greater axial extraction forces

EJOT ALtracs® Plus compared to non-circular screws

The design of the ALtracs® Plus thread geometry enables ideal exploitation of the material properties.

Significant assembly safety due to high overtorque
High and constant preload forces due to reinforced nut thread flanks
Minimal creep tendency under thermal load and/or dynamic load through large thread overlap
Reduced screw-in depth is possible, i.e. shorter screws, smaller components, less weight, more favourable wear conditions in the die-casting tool
Good repeat assembly
High vibration resistance

Unlike other thread cross-sections, the ALtracs® Plus thread is completely engaged on its circular perimeter and fully loadable.

This, together with the higher load capacity of the geometrically reinforced nut thread, results in the following advantages in practice