Keeping the lifter lifting

21 June 2021

The installation of condition monitoring devices on gearboxes and cable reels allows fruit processing company, Zentis, to monitor the health of a critical pallet lifter to help prevent unplanned downtime and optimise production.

The pallet lifter – 1500kg nominal load – is vital to the production process, handling around 600 pallets of fruit that is delivered daily. Zentis wanted to be able to ensure that there was no unexpected failure of this important piece of equipment. I identified that it would be possible to use vibration measurement to obtain information at an early stage about any possible signs of wear or damage. A key challenge, however, was the short interval during which measurements can take place. Constant measurement conditions only occur during the ascent and descent operations of the pallet lifter – a duration of just six seconds.

If the pallet lifter fails, the first production stoppages would occur about two hours later. Longer downtimes of the high racking store would have serious implications on all production lines. In percentage terms, around 60% of production volume would be lost after four hours of the pallet lifter being shut down. After six hours, around 90% of production volume would be lost.

Early warning

In order to monitor the pallet lifter, three SmartCheck condition monitoring units from Schaeffler, units were installed on the machine. The monitoring concept is based on an alarm triggering in response to a change in characteristic values. The alarm outputs of the SmartCheck units were connected to a SmartConnect Box and onward to the control system.

The SmartConnect Box acts as a distributor of power supplies and additional signals. It also significantly reduces the amount of cabling required between the various condition monitoring devices and control system.

SmartCheck can be used to monitor vibration and temperature, as well as a range of other machine and process-specific parameters such as speed and load. By monitoring these parameters, users are provided with actionable information in real time to enable accurate assessment of machine condition.

Due to its self-learning mode, the device’s alarm thresholds are adjusted automatically. After set-up and commissioning, the unit operates autonomously. The relevant machine parameters are measured and saved continuously in the system, creating a substantial database of historical data over time.

Using a simple ‘traffic light’ warning system on its status display, SmartCheck provides early indications if limit values are exceeded. It helps to prevent bearing/gear failures and any associated machine downtime. If imbalance is detected that is outside the ‘normal’ pre-set limits, the status display changes from green to yellow. However, the machine can still continue in normal operation. A red warning indicates that action must be taken immediately.

Customer benefits

The predictive maintenance solution implemented by Zentis has increased its production efficiency. The condition monitoring solution effler has enabled an early warning period of several weeks. Through early warnings the internal maintenance team at Zentis can now carry out any necessary preventative repairs to the pallet lifter as part of planned maintenance work, preventing any costly unplanned downtime.