Been doing this a long time. Seen a thing or two. I admit I stole that from the insurance commercial but it’s true. Experience is something that can’t be learned in college unlike the way it’s learned by being there. By experiencing the situation firsthand.
Recently, I had occasion to be a part of an accident investigation team for a tall reach truck tip over. No one was hurt, thank goodness, but the forklift is totaled. The EH&S needs to know how it happened to try and prevent it from happening again. During this process, I began taking stock of all the incidents and information I’ve been privy to over the years and noticed a pattern. It was often the result of something no one thought of when designing the forklift, rack, or process. I’ll cover the cause at the end.
To prepare for the future, learn from the past
One early example I remember includes what we call a chain slack switch incident. It seems that the hydraulic mast can collapse if the carriage of a man up orderpicker gets hung up on the rack. Sure, it’s a little bit of operator error in getting hung up but this operator was injured. He was completely surprised when the carriage free-fell 10 to 15 feet after he pulled away from the rack. He didn’t know. Now the chain slack switch limits that free fall to just a couple of feet.
Another example included the simple fact that old technology sometimes resulted in the welding of contact tips. For either travel or lift, this was a dangerous situation and I know of injuries as a result of both. Today, the electronics are much more reliable, and this issue seems to have gone away.
Did you know that all reach trucks have the option for a ‘rear operator post’? This post is designed to prevent an operator from backing up and getting trapped under a load beam of the rack behind him. There are several ways to prevent this rack/forklift interaction including overhead guard posts, and a rack redesign including beams at the floor level. Long ago, the problem of welding contact tips and the lack of the rear operator post resulted in injury. No more if the rack and/or forklift are designed to work together.
Not too many years later, a rolled plastic sheet company had a roll of plastic telescope after the overhead guard of a reach truck tapped it. The telescoping plastic roll came out of the rack, and into the operator compartment. Those rolls are now all in cradles, and no longer stored by handling with a pole.
Look up and down, and all around
Have you ever seen a tall, very narrow aisle turret truck system? You may not have noticed but the floors are designed to be ultra smooth and flat. The gap between the man up carriage and the rack is often only six inches. Travel with that narrow of a gap requires the rack to be perfectly straight, the floor to be smooth, the guidance system to be straight, a careful look at the loads (to ensure nothing sticks out), and a strict training regimen to make sure operators are comfortable. I’ve seen a couple of our used rack friends put together systems without properly understanding the floor requirements resulting in damage and danger. One system was taken down shortly after it was put up. I wonder who paid for that?
Roll form racks are not as durable as structural rack. When paired with a reach truck, it’s important to know the base leg overall width, compare the beam length, and pay attention to the base plate and anchor placement. The right design can greatly minimize how many uprights you’ll have to replace. Thus, designing in the correct guarding not only saves money in repairs year after year, but it can also reduce the risk of a rack collapse.
Drive in racks have their own special overhead guard height considerations. You can buy a special narrower carriage for your reach trucks. Keep in mind that it costs a lot less when you order it right from the factory.
Live and learn, a lot
3,000 lbs. means 3,000 lbs. I had one client who told us the load was 1,600 lbs. and the capacity of the lift truck was 3,000 lbs. The load was actually 3,200 lbs. because the client and a second vendor who designed the rack were planning on storing a double stacked load. The client was surprised when the swing reach leaned over while traversing the load into the topmost pallet location, but not as surprised as the operator. I was the service technician that went up and rescued the truck from its stuck position!
Tunnels require special training. We all know that forklift operators are trained to watch out for doorways and overhead obstructions while traveling. When designing a system with tunnels, keep in mind that the operator must be reminded to practice a no travel until load is fully lowered process to avoid crashing an elevated mast into the tunnel.
Mixed deep reach and single reach rack systems should have pallet stops at all elevated locations to prevent the deep reach truck from pushing a pallet through a flue. Deep reach trucks often have shorter load backrests to reduce the interaction with beams. Deep reach racking should have bay openings increased to allow for more lift off.
Freezer floors in older buildings may heave. Pay close attention to floor levelness when elevating loads. Reach trucks will tip over if loads are elevated on uneven slabs.
The latest incident involving the reach truck tip over seems to have been caused by a combination of factors. A rack design that had pallet backstops in a travel aisle at the same height as the overhead guard was one factor. An indicator of the problem is the marks that clearly show a large number of interactions with the reach truck overhead guards. Scrapes, deep scratches, and bent metal on both the rack and the forklifts were considered “normal”. The aisles were tight, making it more likely that the interaction would occur. The training program failed to address this hazard (being unaware of it) so the operator, during the normal course of elevating, turning and traveling into position to retrieve a pallet on the top level was unaware of the danger. To be clear, the operator’s action caused the tip over. Forcing travel after the OHG hung up was basically like doing a wheelie on a bicycle. Pull on the handlebars and pedal hard. The trouble is the elevated mast made the center of gravity very high. It did not take much to get past the fulcrum and it looks like no one had experienced that problem before. No one expected it.
Sharing more than knowledge
Sharing years, even decades of experience is where we excel at Abel Womack. We’re happy to take a look at your warehouse and operation. Just remember when you call, expect us to bring all that experience and wisdom along too!
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