Hydraulic cylinders are involved in heavy work in industrial applications; for example, in excavators, presses or machine tools. The demands placed on their service life in particular, are correspondingly high. This is why manufacturers focus on endurance strength even at the development stage. Ultimately, only components that have proven successful under sustained loading go into mass production.
Developers use special test benches to determine the fatigue life and endurance characteristics of hydraulic components in terms of operational performance, operating hours, and load cycles. On these test benches, they also simulate – through targeted interference effects – error states and troubleshooting options. A renowned hydraulic cylinder manufacturer commissioned a-solution with the task of modernization of one such development test bench. The aim was to continue using the hydraulic setup and only the measurement and control equipment was to be replaced. The measurement and automation solutions expert chose standard components for implementing the new system. They also used HBK’s QuantumX data acquisition system, which, in this context, impressively demonstrated the advantages it offers to users – such as the possibility of easy integration with existing systems through EtherCAT.
For the modernization of a development test bench, a renowned manufacturer of hydraulic components set a clear task: A modern test system was requested, which would allow the cyclic loading of test samples in endurance tests over several months – this corresponded to approximately 10 million load cycles in typical applications. To this end, the hydraulic setup would be continued to be used and only the partially defective measurement and control equipment had to be replaced – with standard components available in the market that use a robust bus system for reliable signal transmission. Last but not least, the customer wanted open, DIAdem-based software to be used to allow for customization through the user and easy data exchange between test staff and developers.
Thus, a-solution implemented a distributed system consisting of three stand-alone test stations (see figure 1), providing a tailor-made solution that meets the customer’s requirements. A central control computer is used for operation and visualization. Every test station has two analog and eight digital outputs as well as 16 analog inputs with a limit value monitoring function that responds to critical signal states within less than 10 milliseconds. Every measurement computer in turn has two measurement amplifiers. In this case, a-solution decided to use HBK’s compact QuantumX MX840B universal amplifier. The decisive factors were its ease of integration with the overall system architecture through EtherCAT, its flexible configuration and high signal quality as well as the 8 data-acquisitions channels, each available per gateway module.
Connectivity, particularly between the measuring amplifiers and the measuring computer, is crucial for the overall system functionality. The interface needs to transfer data in real time and at high data rates to be able to ensure the requested response time during limit value monitoring. For this reason, a-solution decided to use the fast Industrial Ethernet Standard EtherCAT and the DIAdem-EtherCAT driver, developed in-house, to ensure easy real-time integration of DIAdem software with EtherCAT. One HBK CX27 gateway module each was used to connect the two QuantumX measuring amplifiers of each test station to EtherCAT. The application could be easily and quickly integrated with the system due to the included QuantumX configuration software that allows for convenient configuration and provides diverse diagnostic options. To achieve this, QuantumX Assistant was opened directly from the DIAdem application.
a-solution’s endurance test bench for hydraulic components provides its customer with an application that enables complex testing tasks to be performed using standard hardware and software components. Signal acquisition can be flexibly adapted to different test setups, with the help of HBK's QuantumX universal amplifiers that allow for parameterization. Real-time response of a distributed, Windows-based system to critical signal states is ensured through signal acquisition and output via HBK CX27 gateway, a-solution DIAdem-EtherCAT driver, and additional EtherCAT hardware. The open software structure, based on DIAdem and QuantumX Assistant enables the customer to adapt the application for future requirements.
