EJOT-EVO-PT
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EJOT EVO PT® The evolution of direct fastening into plastic The EVO PT® is the evolutionary development of the self-tapping screw for thermoplastics. With this innovative fastening solution, EJOT has successfully combined production and application technology knowledge with new methods based on physical computer simulations for the first time. Digital service for optimised components The digital calculation service EVO CALC® offers the possibility to pre-calculate the torques and clamp loads as well as the clamp load relaxation under temperature and time. Furthermore, EJOT provides an individual, FEM-based component analysis to save valuable time and money - beginning with the design of the component. Simple and universal design recommendation for EVO PT® screws Innovative thread geometry for high fastening quality and high repeat accuracy Since the forming thread turn generates a virtually constant forming torque, a compensation of different clamping part thicknesses by means of different counterbore depths is not necessary. As we assume to have injection-moulded pre-holes which usually have a draft angle of 1°, the pre-hole diameter of 0.85 x d1 is measured at the top of the pre-hole. For a better measurability, the pre-hole diameter db at the top of the pre-hole is given as 0.85 × d1. The newly developed "start-of-thread" of the EVO PT® allows for an easy and straight positioning in the screw hole. The special positioning thread thus generates an equal load distribution over the circumference of the thread flanks in installed condition, since the screw is centered automatically in the screw hole during the installation. Increased economic efficiency through reduced parts variety and higher process safety in assembly During the installation phase, the innovative forming thread turn creates a torque curve which is virtually independent of the installation depth. The thread forming zone forms a thread turn into the female material which is slightly larger than the clearance that the following thread turns require. The following thread turns can penetrate into the plastic without any appreciable friction. This enables smaller installation spaces or a standardisation of screw lengths and tightening torques. Nominal diameter of the screw: d1 Counterbore diameter: dE = d1 x 1.05 Hole diameter: db = 0.85 x d1 ± 0.05 mm Installation depth: te = 2 x d1 or deeper dT = external boss Ø dh = clearance hole Ø dE = counterbore Ø db = hole Ø ts = counterbore depth = 0.1 x d1 te = installation depth tc = hole depth allowance

Characteristics and features of the EVO PT® screw Thread forming zone Reduced friction during thread forming Bionic contour Safety margins for challenging applications • Higher fatigue strength • Higher breaking torque • Higher tensile breaking stress • Thread forming torque is virtually independent of the installation depth • Installation-depth-independent tightening torques • Reduced parts variety - one screw, one tightening torque per assembly group • Uniform tube design • Supports carry-over part strategies Large torque window thanks to small installation torque Me • High installation...