The forklift manufacturer Crown relies heavily on robotic welding automation for fabrication/production of their equipment in the Roding (Germany) facility.
The company has now begun to replace the time-consuming manual teaching of the robot systems with simulation-based offline programming for tool path generation. For this, the company relies on the FASTSUITE Edition 2 software and the CENIT team.
Crown is one of the five largest forklift manufacturers in the world. The US-based, family-owned company has a global production, sales, and service network with 19 manufacturing sites around the world and more than 500 sales offices in 84 countries. As a customer-oriented innovation leader, Crown regularly sets trends in the field of material flow solutions.
For the production of forklifts, it is critical to develop robust and durable products that meet the customer's high demands for quality, ergonomics, and reliability, as well as meeting safety-relevant requirements. High quality standards based on a customer-oriented focus are met by Crown's high vertical integration: up to 85 percent of the components are produced in-house.
Crown has been producing forklifts in the Roding facility since 1986. Today there are several complex robot systems with up to 13 axes in the production floor. Programming and fixture construction play an important role. However, some of the solid steel components have seams that are difficult to access or many welds on a small area. This makes manual teaching and fixture construction difficult.
For some time, Crown has been considering using offline programming. Florian Braun, project manager in manufacturing engineering, saw an opportunity to optimise the use of welding robots. One supplier convinced the team: The IT and software consulting company CENIT, with its software FASTSUITE Edition 2, could fulfill their requirements. The 3D simulation platform offers a sophisticated technology package specifically for offline programming of welding processes. A benchmark was set to program a component with the OLP software on a Reis compact weld cell and perform a download. Above all, it was judged how well the download works and how close the robot follows the contour of the weld path.
The software features required by Crown:
- CAD data-based welding seam generation (CAD-to-path algorithms) with automatic approach and departure strategies. Welding path generation not only describes the robot's motion paths, but also includes the control commands for the welding technology. In this way, many manual programming steps are avoided and optimal process parameters are always used.
- The parameters for the weld seams and the positioning of the torch to the workpiece can be easily adjusted if required.
- External axes and workpiece positioners are automatically positioned and interpolated.
The performance of FASTSUITE in the field test was convincing to Crown. Although the cell had not yet been calibrated and prepared for offline programming during the test, the toolpath was already very close to the expected result on the test part. FASTSUITE was able to demonstrate its "ease of use" and the high level of expertise in welding production that CENIT brought gave Crown additional assurance that they had found the right partner.
The implementation project had three phases.
At startup, CENIT configured the software for the requirements of the corresponding system (phase 1). This was followed by the creation of a digital layout model of the cell (phase 2) that corresponds to the real installation. At the customer's site, phase 3 began with the calibration of the facility with the digital model.
The result: The first welding cells were integrated into the simulation environment at the beginning of summer 2017. Instead of taking several days, programming a new workpiece or part variant now only takes a few hours. This is because the programming takes place in the simulation environment of FASTSUITE Edition 2 (offline, i.e. parallel to the productive operation of the system) and as a result the downtimes of the system have been significantly reduced. The production interruptions for setting up and teaching new components has also been reduced to a minimum. The welding quality of the solid steel parts are consistent and corresponds to Crown's high standards.
In summary, the OLP project has had a positive impact on streamlining the development and design of toolmaking. It is much faster and easier to determine the right fixture because the simulated system is available with all kinematics and peripherals as a virtual 3D model. Instead of testing the real device prototypes over and over, the virtual device can be tested for accessibility and then built in real life. New components can be optimised during development for later welding production.
New ideas are already emerging in the Roding facility today. With FASTSUITE, Crown has a software solution that they can grow with, it is open and scalable – and an ideal first step for a company with a strong Industry 4.0 vision.