Modern high-performance electronics are literally live. As they face increasingly stringent requirements, no errors are acceptable in assembly. This is why Germany’s leading manufacturer of laboratory power supplies has changed its assembly process over to tightening tools with monitoring functions from Atlas Copco Tools which already detect and eliminate any errors during the tightening process.
“Nowadays, no electrical laboratory and no research institution can do without unidirectional and bidirectional DC power supplies or DC electronic loads with recovery functions,” says Markus Stops. “These units are essential for testing vehicle electronics and high-voltage components of all types.” The tests needed in connection with electro-mobility, which are becoming increasingly important, would scarcely be possible without this equipment, according to the production manager of EA Elektro-Automatik GmbH & Co. KG (EA) in Viersen, who explains the importance of these unimposing high-tech units, which are only 19 inches wide. The compact white metal housings of these innovative units give no indication that they return up to 96 percent of the energy used to the mains after they have done their work.
96 percent efficiency
“EA is regarded as the inventor of electronic loads with recovery functions and we have recently been able to reduce the power loss to only four percent, the production manager explains with justified pride. He says that this is a world-class achievement, saves costs and also avoids the need for complex cooling systems. Markus Stops admits that the units look relatively inconspicuous; you cannot see that up to 75 function- and safety-critical tightening operations are needed during assembly.
He says that it is absolutely essential to complete these tightening operations correctly, with the right torque values. If only one of these joints failed, it could lead to the shut down of an entire facility. For this reason, EA used to test all the relevant joints following assembly, says Stops, taking us on a tour of the production facilities. The manufacturing depth at the plant is high and includes circuit board assembly as well as the production of entire semi-finished components, comprehensive performance tests and final assembly. “Our objective is to retain our skills within the company by maintaining the highest possible manufacturing depth and to stay up-to-date with all the key production steps,” the production manager emphasizes.
Monitoring to prevent errors
As the most recent example, Stops mentions the changeover to entirely new tightening tools for assembly: “In order to achieve maximum process security and quality, we want to ensure that our assembly processes are monitored seamlessly and the tightening data are evaluated.
This way, we can use the data for further quality improvements. It would not have been possible with the battery driven tools we had previously used. This is why we took up the offer of our tool supplier Tools-Technik-Gilges to try out an innovative MicroTorque system from its partner Atlas Copco Tools.”
This system was to significantly simplify the testing of critical joints and to make further tests superfluous following the successful completion of the trial phase.
An easy start
“The commissioning of the first system was already extremely easy and intuitive,” reports Frank Schriefers, deputy head of production at EA.
“Using the soft buttons on the MicroTorque controller, I was able to set the torque value of 100 Newton-centimeters required for the assembly of our electronic loads and the ideal tightening speed in only a few seconds. Programming with the controller is much more precise and convenient than the mechanical adjustment and checking of the torque on the shut-off clutches of the battery screwdrivers previously used.”
Frank Schriefers, deputy head of production at EA Elektro-Automatik GmbH & Co. KG
In contrast to those tools, the MicroTorque units are equipped with an electronic transducer and work considerably more precisely, without any temperamental mechanical systems.
Tool thinks for its operators
As soon as the MicroTorque system has been programmed with the customer’s individual assembly requirements, the operator can virtually make no more mistakes, says the manufacturer. “The tightening torque and angle for each individual joint are monitored. This way, the possibility of incorrectly tightened screws is practically excluded,” says Schriefers. For example, if a screw with defective thread is inserted or the operator releases the starter lever of the tool too soon, the MicroTorque system immediately initiates an alarm and requests remedial action. In addition, the integrated batch counting function means that a screw cannot simply be forgotten during the assembly sequence, say Frank Schriefers and Markus Stops, reporting on their positive operational experiences: “The counting function supports the operator and makes the process more secure. This way, the intelligent monitoring functions allow us to eliminate subsequent testing steps.”
Smart networked use of assembly data
Thanks to the consistent monitoring of torque and rotational angle, it is not possible for incorrectly assembled modules to leave the production station without detection. The Atlas Copco system with documentation provides EA Elektro-Automatik GmbH & Co. KG with additional security. Using the recorded data, the electronics producer from Viersen can rapidly demonstrate that each joint in the production has been tightened precisely in accordance with the applicable specifications if a complaint arises. For this reason, Stops und Schriefers already incorporated five more of the ESD-certified Atlas Copco screwdrivers approved for use in clean rooms in the production facility after a very short time.
Productivity boost of 30 percent
“Our expectations as regards ergonomics, quality and process safety were entirely fulfilled. We have now changed our assembly facility over to MicroTorque equipment,” Markus Stops emphasizes.
“Thanks to the easy handling of the flexible system and the fact that we no longer need to carry out certain tests, we have been able to improve the overall productivity of our assembly by an impressive 30 percent”
Markus Stops, production manager of EA Elektro-Automatik GmbH & Co. KG
