Motion Control Resources
Groundbreaking technologies in heavy-duty applications
by WITTENSTEIN with TECHNIK
WITTENSTEIN Posted 05/28/2020
Our smart drive for bolting systems
A newly developed encoderless synchronous motor and high performance electronics with a wide-range input and smart software from WITTENSTEIN cyber motor give alki TECHNIK GmbH’s electric torque multipliers not just plenty of drive power but also intelligent data acquisition in line with Industry 4.0 principles.
Extremely robust high-end solution
Harsh surroundings and severe stresses are the norm in the characteristic operating environments for heavy-duty torque multipliers. Bridges, tunnels, power plants and wind turbines are just a few of the typical construction applications. Bolts with M160 threads or larger have to be tightened here. And torques of up to 200 kNm are the order of the day. To ensure high availability and accurate performance under these extreme conditions, alki TECHNIK chose an intelligent drive system from WITTENSTEIN cyber motor in the power class up to 10 kN for tightening screws with thread dimensions up to M95.
WANTED: BOLTING SYSTEM WITH FUTURE POTENTIAL
Electric torque multipliers are used whenever high torques, fast operating speed, exact precision or a large number of joints are called for.
alki TECHNIK set out to develop an innovative bolting system that would enable it to expand its portfolio in this segment. New operating modes for complex bolting processes were at the top of the specification list. More extensive control and communications intelligence was also a key priority, so that these processes could be monitored and documented more accurately. The new bolting system additionally needed to provide an integrated user interface and meet all the fundamental requirements for Industry 4.0, including data logging and Bluetooth®. The redesign of the drive system was entrusted to WITTENSTEIN cyber motor, who are in the business of customized motor and electronics development. The customer was particularly convinced by the development of the necessary software with Industry 4.0 functionalities.
FUNCTIONALITY – THE KEY LIES IN THE SOFTWARE
The newly released test box from WITTENSTEIN cyber motor is a perfect addition to the torque multiplier.
This programmable controller (PLC) is used in the alki TECHNIK production process. The torque multiplier being assembled is connected to the box and parametrized – in other words, the mechanic sets the optional operating modes, assigns a gearbox size and a serial number and in doing so defines the multiplier’s customer-specific functionality. Once the bolting system has been set and tested with the box, an inspection certificate is issued automatically. The torque multiplier can also be simply connected to the test box for servicing, for example in order to read out error messages and operating data. It can then be reset to the as-shipped condition.
A development project full of innovation
Through our systematic application of the MINI strategy, which at WITTENSTEIN stands for miniaturization, intelligence, networking and integration, we succeeded in packing a very compact drive into the customer’s torque multiplier housing. One particular highlight of this solution is that, thanks to the special encoderless control with maximum torque, it can start up and then position from standstill. Encoderless commutation was a key success factor because the encoder system which was used in the past made global servicing very difficult. In future, the customer can service the torque multiplier directly in the field. Apart from the cost saving this also enables significant economies of time.
Owing to the wide-range voltage, between 110 VAC and 230 VAC can be supplied, so that the bolting system is ready to use anywhere in the world. Moreover, the power supply unit compensates grid-related voltage variations which could otherwise cause the product to fail, thus contributing effectively towards optimal EMC behavior.
Innovative software enables new functionalities
The electronic hardware and software are based on WITTENSTEIN cyber motor’s modular electronics platform. Customer and application-specific requirements – both technical and commercial – can be realized very efficiently in this way. The latest generation of processor technology is used to achieve fully digital control. The new torque multipliers can consequently be enhanced with smart protection and monitoring functions. The control characteristics, too, are much better, leading to high repeatability. Furthermore, several torque multipliers can now be operated in sync.
This function is especially useful for bolting processes where the end customer needs to tighten a set of bolts more or less simultaneously, e.g. on the cylinder head of a large diesel engine. The new system maps complex bolting processes in up to seven different operating modes – and using the innovative software different modes can be set on each torque multiplier. Customers specify which functionality they require when ordering, though upgrades are also possible at any time.
Connectivity makes the difference
The bolting system has a configurable, process controlled memory unit, which acts as a data logger for recording and storing the bolting torques. The data for each bolting process can be read out directly on the construction site using a smartphone or tablet which is equipped with a wireless Bluetooth® module. However, data logging and wireless transmission do not simply broaden the array of potential applications for the bolting systems; they also prepare them for Industry 4.0. The fully integrated user interface with display and keyboard control opens up a whole series of customizing options to also make servicing and maintenance more straightforward. “Our worldwide dealers will no longer need to return defective torque systems to our plant. In most cases they’ll be able to repair, exchange or program them per plug-and-play on the spot. This is more cost efficient, faster and therefore in the user’s interest”, explains Alexander Kipfelsberger.