In the first part of our Expert Hub series on seating control, our assembly expert Michael Laue describes what happens in a bolted joint after the seating point has been reached.
The second part deals with the question of the joints and torque ranges that the seating control strategy is suitable for.
This part provides specific information on how customers can benefit from the seating control approach in their everyday work. In addition to presenting a practical example, we also demonstrate how you can use the knowledge and expertise of Atlas Copco Tools for your work in connection with assembly:
Expert Hub: Mr. Laue, you and the Atlas Copco Tools Tightening Service Team have already carried out dozens of tightening analyses and have been able to demonstrate the feasibility of seating point detection. Could you give us a practical example of the added benefit to the customer of using the seating control strategy?
Michael Laue: Certainly. I have deliberately chosen an example from furniture production rather than from machinery assembly. It is a mistake to assume that the use of screws in wood is simple. Because of the non-homogeneous nature of the material, joint tightening is often a complex matter.
A company in the furniture industry had to tighten thread inserts into various particle boards made from different materials. The thread inserts had to be tightened in slightly below the surface of the particle board so that the boards would not cause damage to each other or possibly injure customers or employees when they were stacked.
There were three main problem areas
- The inserts were to be tightened into different materials which were non-homogeneous
- The inserts were to be installed in pre-drilled holes in the chipboards by industrial processes and there was some variation in the diameter of the holes
- The customer expected the assembly process to deliver stable and high-quality results
Solution:
The non-homogeneous material and fluctuations in the hole diameter were simulated in a tightening analysis with a view to adjusting seating point detection to material fluctuations. This approach was successful.
It was possible to reliably detect the seating point in all types of particle board used for furniture with an Atlas Copco Power Focus 6000 LV controller combined with an SMT torque arm and an ETD SL21 04 I06 PS tool. Following seating point detection, the thread insert is turned by a defined angle. This prevents damage and injury during handling of the boards.
Thread inserts in wood
Results:
- Quality improvement at the customer’s production facility
- Proactive avoidance of injuries and damage
- Greater customer satisfaction, safer working for employees
- Lower reject costs caused by damage to particle boards
- More reliable processes
- No expensive modification of industrial drilling or particle board production processes required
Expert Hub: These benefits sound convincing, Mr. Laue. Is there any difference between the approach to finding a solution with seating point detection and solutions with a conventional tightening strategy? How do you support the customer on the way to finding a solution?
Michael Laue: No, the approach is basically very similar. To define the parameters for the tightening process with seating control, several tightening tests must be performed.
However, customers need not worry as we offer all the services required from a single source (see link for downloading “Seating point detection in five steps” below).
These five steps indicate the typical procedure for designing a tightening process with seating control. Further information is provided in the flyer (link for downloading below) or can be obtained direct from our Tightening Service Team (contact.po@atlascopco.com).
For Atlas Copco, sharing our knowledge is part of our corporate culture. This naturally also applies to our customers. We offer customers a wide range of training events and workshops connected with tightening technology. For example, we have one-day seminars on direct tightening. Additional information is also available. A flyer (see below) presents our seminar on self-forming joints. This is certainly relevant to many potential customers who would like to know more about seating point detection.
Expert Hub: Mr. Laue, thank you very much for this interview.
Download our flyer "Joint analysis with seating point detection":
- Flyer joint analysis with seating point detection in the laboratory 745 kB, PDF
- Tightening technique - direct tightening 2 MB, PDF
- Seating point detection in five steps 166 kB, PNG