The Evolution of Direct Fastening into Plastic
Benefits
EVO CALC® Software validates applications, speeding up engineering development time
FEM based relaxation forecast under temperature and time
CAE- Computer-Aided Engineering for complete assembly groups
Standardization potential of single screw length due to unique thread forming zone approach
EVO-Effect (Low installation torque and larger drive to strip window)
Features
Newer Lead-In thread feature for automatic screw centering
Bionic Contour for optimized plastic thread forming
26° flank angle
Oversized initial forming thread
FEM Analysis of the Screw Joint
Stress Analysis in the Component Under Load
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 optimized components
The digital calculation service EVO CALC® offers the possibility to pre-calculate the torques and clamp loads and 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 component's design.
Simple and universal design recommendation for EVO PT® screws
Since the forming thread turn generates a virtually constant forming torque, a compensation of different clamping part thicknesses using different counterbore depths is unnecessary. As we assume to have injection-molded 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 better measurability, the pre-hole diameter db at the top of the pre-hole is given as 0.85 × d1.
Innovative thread geometry for high fastening quality and high repeat accuracy
The newly developed "start-of-thread" of the EVO PT® allows for easy and straight positioning in the screw hole. The unique positioning thread thus generates an equal load distribution over the circumference of the thread flanks in the 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
The innovative forming thread turn creates a torque curve virtually independent of the installation depth during the installation phase. The thread-forming zone forms a thread turn into the female material, slightly larger than the clearance 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 standardization 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
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 Ti
High installation reliability
High plant availability
Compensation for process fluctuations
Lead-in thread
Automatic centering of the screw in the screw hole
Stable installation process during initial assembly
Line-integrated, fully automated repeat assembly
Constant, low-stress surface connection
Smaller counterbore depth
Less installation space is required
Usage of purchased parts possible without unloading
Automatic compensation in case of axial misalignment (screw/screw hole)
Compensation of component tolerances
Bionic Contour
Safety margins for challenging applications
Higher fatigue strength
Higher breaking torque
Higher tensile-breaking stress
26° flank angle
Excellent plastic forming
One flank geometry, suitable for all common thermoplastics
Reduced radial load in the component
EJOT EVO PT® – is all about you
Everyone is taken care of
Our role is to support your design work even before your customer orders. Together, we can incorporate the positive benefits of direct fastening into plastic into your assembly application at an early stage. At the end of the day, the new EJOT EVO PT® is all about you, a better result for your customer, and, ultimately, your economic success.
We want you to
• plan and produce in a cost- and time-optimised way
• produce process reliably and without errors
• enthuse your customers with your quality before and after the order placement
• receive the order
• quickly have your product ready for serial production
As a manufacturer of products and components, you not only have to control your production, but every process in your company impacts your overall success. That‘s why we keep an eye on the requirements of all persons involved in the overall process and provide you with measurable advantages thanks to the EVO PT®.
Advantages for
Design Engineers
- Maximum mechanical safety
- Precise performance forecasting
- No thread inserts necessary
- Relieving the time budget
Advantages for
Process Engineers
- Maximum plant availability
- Maximum process reliability
- Consolidation of parts
- Error avoidance
- Harmonised assembly concepts
Advantages for
Quality Managers
- Reduced effort for sampling, series, and inspection
- Low error potential
- Consolidation of parts
Advantages for
Purchasers
- Competitive purchase prices
- Consolidation of quantities
- Reduced complexity
- Low total project costs
- Consolidation of suppliers
Your intelligent planning services
When configuring and using EVO PT® screws, you may benefit from these exclusive services:
EVO CALC®
FEM
CAE
Preliminary Design of your Screw Joint with EVO CALC® 
The prognosis program EVO CALC® especially developed for this screw enables the fast and precise determination of all values and information concerning the installation of the EVO PT®, which are essential for your project.
This comprises, for example, creating a design recommendation, calculating the relevant torques, determining different forces, such as the clamp load at the tightening torque, and presenting possible failure modes in case of overload. The results provide immediate information on whether your assembly group is already optimally designed for your requirements or what has to be done to achieve your optimum.
If you have any further questions, please do not hesitate to contact your application engineer.
Details are taken from the prognosis program EVO CALC®.
Advantages
- Prediction of torques and clamp loads
- Early identification of failure risks
- Downsizing suggestion
- Saving of component tests
Additional Family Products
New Thin Thread Technology for Thermoplastics
Data Sheet(s)
