Adding a new automatic glass unloading machine to your line of equipment is one of the best ways to improve productivity while protecting your staff and your inventory. However, it's not just the productivity that's a concern. What happens while the machinery is handling the glass and how it handles variations are just as important, of course. When you start checking out specific models of unloaders, be sure the model you get meets these standards to ensure the best outcomes as you start moving glass sheets through the system.
Can you watch the model in action? The entire process of picking up a glass sheet and moving it through the machine should be smooth, with no close calls that make you think a glass sheet is about to break. You want to be sure that there are no times when you have to sit there and hope the machine doesn't damage anything. Do your best to see the specific model actually move a sheet through its system.
If a machine has a motor, there's going to be vibration; that's normal. But good machinery should have vibration-damping systems in place so that parts don't start to shake uncontrollably, and so that glass moving through the machinery doesn't break. Even if you are moving tempered glass through, a break would result in stopped machinery, lost time, lower productivity, and one heck of a mess. As the machine operates, look at how much parts of it are shaking. Stand as close to it as is safe (and wear all appropriate safety gear) and try to feel for vibrations through the floor. Sometimes those vibrations can transfer into other nearby machinery and affect how those machines work.
If you have coated glass (like low-emission glass) that needs gentle handling, look specifically for a glass loader/unloader that will handle that type of glass. Some loaders are just rough enough that coatings end up with small scratches after the glass runs through the machine. But machines that are designed to hold coated glass are much more gentle and generally do not damage the coatings.
Glass is a special product because it can cause such trouble if it breaks. Any machinery that will have glass sheets running through it must be set up so that the operation of the machine does not ruin the product. It's essential that you inspect machines and watch how they operate before you commit to buying one.