Challenge
Minimize waste and downtime from imperfect log cuts.
Solution
Laser measurement sensors, a PLC, a presence/absence sensor, and a tower light.
Story
Anything that is manufactured has the potential for defects. That seems obvious on a high-speed production line making custom components for the automotive, aerospace, or medical field, but non-traditional manufacturing environments have defects too.
A pallet manufacturer approached the engineers at EMP about a recurring defect. The customer makes pallets by first cutting each log into planks. The planks need to be a certain width with straight cuts on each side. If either requirement is missed, the plank cannot be formed into a pallet and is scrapped.
The EMP engineers designed a solution to minimize that scrap. After the initial cut, each plank is placed on a conveyor. As it moves down the conveyor in a guided position, a presence/absence sensor tells the PLC whether a 40-inch or 48-inch plank is being run. Two laser measurement sensors on either side of the plank measure the distance from the sensor to the wood and send it to the PLC as a voltage. EMP wrote a custom program to compute the overall width of the plank, accounting for any curvature on either side.
The two laser sensors also take measurements every two inches to verify that each side of the plank is straight. All of this data is captured in the PLC and stored to a file for future reference. The system has greatly reduced the customer’s scrap and improved their bottom line.
Have a recurring manufacturing defect? Reach out to the engineers at EMP today.
