Unauthorized modifications to material handling equipment can be trouble

In this edition of In the Trenches, Acme learns that unsafe production processes prove expensive.

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Years ago, Awnuld Faiblesse vowed he'd never be scrawny. Ever since then he pumped iron. He lifted weights before he went to work in the morning, he sat on a weight bench in the back of the maintenance shop and did curls while eating sandwiches at lunchtime, and after work he went to his health club. No doubt about it, Awnuld worked out and it showed — he was in shape. He seemed almost comical to the folks in the plant because they could tell when he was coming their way from the rhythmic squeaks of his hand grip strengtheners.

On the business side, as a member of the mechanical gang at Acme, Awnuld prided himself on his ability to screw things together tighter than anyone else. You see, Awnuld believed that if he got things tight enough, they just couldn't break. He really didn't concern himself with disassembly. After all, what were cutting torches for?

About a month ago, Acme's production manager Luther Quick requested that maintenance modify a forklift for use under a mezzanine. The mezzanine was installed next to a loading dock to double storage space and so parts could be transferred directly to the appropriate workstation with the least amount of material handling. The only problem was that no one verified the overall height of the forklift trucks and now none would fit under the mezzanine. Thus came a quiet request from Luther for maintenance to modify at least one forklift to accommodate the less-than-adequate height of the mezzanine.

Maintenance engineer Titus Flint understood the situation all too well. He had backed Luther in the cost reduction and productivity improvement plan that called for the mezzanine, and now he couldn't let that project go sour. So he assigned Awnuld the task of modifying the forklift by installing smaller wheels and making the overhead guard lower and removable so the lift truck could travel under the mezzanine.

Late in the day, Titus called Awnuld to his office and told him that he needed a special job done that evening and asked if Awnuld wanted the overtime. After a moment of thought about getting to the gym later than usual, Awnuld agreed.

Titus then laid out the job of modifying the lift truck — replacing the 14-in. wheels with 10-in. wheels, sawing four inches off the overhead guard cage supports and drilling holes to accommodate push-button type locking pins. Titus explained this would make the overhead guard cage easy to remove by simply depressing the spring button on the shaft of the locking pins.

Awnuld told Titus that he understood what was needed and would take care of the job before he left for the day. This put Titus' mind at ease — a minor modification on a forklift truck to avoid a major material handling faux pas.

Awnuld went to work on the lift truck. The job didn't take nearly as long as he expected. Within a couple of hours, the overhead guard cage was four inches lower than it had been. Unless somebody looked closely, there was no way they could tell that any modifications had been made. Changing the wheels was a snap for Awnuld. He felt proud of himself as he stepped back and reviewed his work. The material handling guys would be able to use the lift truck starting on the midnight shift. Then it occurred to him that he ought to make sure that those wheels didn't come loose. So Awnuld got a persuader — a two-foot long piece of pipe to go on the wrench handle — to be certain the nuts were really tight. As he gave the nuts one last healthy turn, he noticed how easily they began to turn. "A persuader sure makes nuts turn easy," he chuckled to himself.

On his way out of the plant, Awnuld stopped by the production office and told one of the clerks to let the material handling foreman know that a forklift truck located in the maintenance area was ready if they needed it. The modified lift truck went back into service immediately. Ely Kroy arrived to pick up the lift truck at the maintenance area almost before Awnuld was out the door.

As Ely drove toward the mezzanine, it occurred to him that there is a better way. If someone would ride on the truck's forks, they could direct him to the right pallet instead of him having to do it by walking down dimly lit, narrow aisles under the mezzanine then walking back or trying to squeeze himself between the lift and the pallets once he drove down the aisles. Ely saw his opportunity in Phil Krate, an inventory cycle counter, who didn't appear to be busy with anything at the time. Phil gladly accepted Ely's offer to soften the boredom of the midnight shift.

Ely's scheme of having a guide on the front of his fork lift seemed to be working. He was actually ahead of production — not much, but ahead. However, every time he backed the lift out from under the mezzanine the truck shook when it hit a broken section of the plant floor. After as many as 15 trips, something went wrong. One of the back wheels broke off the axle, the truck spun out of control and flipped over. The overhead guard cage that was supposed to protect the operator went flying and Ely lay unconscious under the truck. A few feet away, Phil lay half under a pallet of subassemblies.

By 3 A.M., Titus Flint and Luther Quick were back at work. The ambulances that carried Ely and Phil to hospitals had left. Now, Titus and Luther had to figure out what happened and what they would tell Acme management. Titus sat in his chair looking at the broken parts. The heads on the wheel lug nuts had clearly failed — they looked as though they'd been twisted off. But that didn't seem to make much sense since a wheel hitting a hole in the floor would likely put a shear load, not a torsion load, on the bolt, wouldn't it? The easy release push button locking pins apparently released too easily. Only one of four could be found and it was bent.

Titus and Luther agreed on one thing: this was not going to be pretty. And pretty it was not. Ely was rendered a quadriplegic and Acme paid out $12,650,000 in settlements. Phil was able to recuperate after a period of convalescence but Titus and Luther didn’t.

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