The typical work day in the production area of a narrow web converting plant requires a multitude of physical and mental skills, well focused and properly exercised. Among the physical requirements for a man or woman operating a press, or assisting in print production, is the ability to move rolls of paper, foil and film to the press, onto the press, and away from the press after the job is complete.
Rolls are heavy. Most often they are stored with the core in a vertical position. To be mounted on the press they have to be turned so that the core is horizontal. A roll of paper for a small job to be run on a 6" or 7" wide press might be manageable for some operators, but the bigger rolls for wider presses present a challenge. They can also present a risk.
In wide web shops, materials handling equipment is standard. Forget lifting a roll onto a 60" press. Forget loading the die or the anilox roll by hand. They have equipment to see that those jobs get done right.
In some narrow web shops, two guys and a broom handle solves the problem for moving rolls of label stock here and there. Turning the roll? No problem. The stick becomes a lever. So you damage a few feet of stock in the process. Happens every day.
Roll protection
The two main reasons for buying and using roll handling equipment are that it improves operator safety and that it allows maneuvering of rolls without damaging layers of the rolled substrate.
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"How do you turn a 600 pound roll?" asks Jeffrey Damour, sales manager for Converter Accessory Corporation (CAC), Wind Gap, PA. "With our unit you can turn a roll without damage. Most guys shove a pipe on it and hang on until it falls over. That way, you can damage maybe 10 layers of the material."
"People today are concerned about safety," Damour adds. "That's probably the main reason they use this type of equipment."
Some equipment available today is designed simply to turn the roll. Others are built to move the roll. A third group can do both. Among products produced by CAC is a fork truck roll handler that allows moving of the roll using a forklift vehicle, as well as turning it when it arrives at press side by use of a pivot arm. Standard production models are available in 3" and 6" ID core sizes; hardened steel grippers engage the core when lifting, and it's impossible to disengage the roll when the center lift is carrying any weight.
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Damour says that the complete cost of the handling unit is around $5,000. The pivot arm alone is $2,350.
Another option for moving rolls is to use a handling unit that mounts onto an I-beam. This type of equipment is available for narrow web operations, but is not as common as in wide web converting shops.
The risk of lifting
Manual handling of heavy rolls — or improper handling — comes with risks that might be greater than if a piece of equipment was used to do the job. "What happens," asks Damour, "if the roll falls over and lands on someone's toe?"
"I'm amazed at some shops," says Harold Sexson, sales manager for Aztech Machinery Equipment, Scottsdale, AZ. "I see guys throw rolls around. One of these days your foot is going to slip You get older"
"With the reality of OSHA trying to limit things, you can't have your guys — in our litigious society — lifting over 40 pounds without complications," says Jeff Chosid, vice president of Conversource, Chesterfield, MO.
"The most important," notes Gerald Morton, general manager of Tilt-Lock, St. Michael, MN, "is that company owners consider using this equipment to preserve the health of their work force. People aren't getting any younger these days."
These days, the government's Occupational Safety and Health Administration (OSHA) has been trying to establish limits on how much a person can lift in the work place and avoid undue risk. Parameters for lifting vary by industry, by size of object lifted, and by the actual lifting performance, so there is no single number that can be waved about as a limit. New OSHA regulations actually were passed recently, but the Congress that took office in 2001 threw them out.
Varieties
Conversource offers several models of roll lifting and turning equipment, ranging from the simple Delta Roll Lift to more sophisticated models. One unit, the RWM Roll Turner, can handle loads up to 330 pounds. The company's most popular product is the Alpha Roll Handler, which takes rolls whose cores are horizontal and slides them onto the unwind of the press. Conversource sells between 30 and 40 of the units each year.
"It's unsophisticated, and uses a cable and a crank," Chosid says. "It takes a roll of paper that's on the ground, lifts it up and puts it on your press."
Tilt-Lock's newest roll handling unit is the Model LD1-3 Tip Lift, which is designed to handle light rolls of paper up to 340 pounds. The lift utilizes ergonomically designed handles, and features interlocking safety switches. "This model is aimed at the narrow web industry," says Morton. "It's small and compact."
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"Normally, most of the roll material in the US is shipped from the supplier in the core-vertical position. All printing machines that I know of use the material with the core in the horizontal position. You have to be able to turn these."
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The LD1-3 features a probe that enters the core, after which internal teeth grasp the core; the harder the lift, the stronger the grasp. "The capacity of the unit depends on the width of the roll," Morton adds.
Aztech Machinery offers several versions of its popular Roll Runner MH 40 series, which can handle rolls ranging from 10" up to 40" in width. Model MH80 turns the roll, and can accommodate weights up to 400 pounds. A tilt table attachment to the roll runner enables the operator to turn the roll.
OSHA, ergonomics, and the mathematics of lifting
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In November 2000, the federal Occupational Safety and Health Administration, known as OSHA, succeeded in having the US Congress adopt new regulations governing ergonomics in general industry practice and various industries within. That set of rules, which became effective January 16, 2001, included language on heavy lifting and repetitive motion. They didn't last. Soon after passage the nation elected a new Congress that had a distinctly different attitude toward business and regulation, and by April 2001 the new OSHA regulations were history. When he signed the bill repealing the regulations, President Bush said: "The ergonomics rule would have cost both large and small employers billions of dollars and presented employers with overwhelming compliance challenges. Also, the rule would have applied a bureaucratic one-size-fits-all solution to a broad range of employers and workers — not good government at work." Lower back pain resulting from occupational injury accounts for 34 percent of the total cost of all occupational injuries and illnesses, according to a 1997 study by J.P. Leigh et al. "The study estimates that the cost for lower back pain in 1992 was $49.2 billion — the most recent numbers I've seen. Compare that with the cost to treat Alzheimer's Disease at $67.3 billion," says Thomas Waters of the National Institute for Occupational Safety and Health (NIOSH). "It's one of the leading reasons for people being off work." He cites research from Liberty Mutual Insurance that the average cost of all workplace injuries is $4,000 per case, but the average for a back injury is $8,000. And lifting, Waters adds, is the primary factor in causes of lower back pain. Waters is a principal author of the Applications Manual for the Revised NIOSH Lifting Equation. This work is aimed at helping companies assess the factors involved in lifting at their operation, and to come up with a set of internal guidelines on their own. "There is no single weight limit for lifting," Waters says. "Horizontal distance plays a role. Whether you lift from the floor or from a table makes a difference. Vertical height of the lift plays a roll, as does whether you twist your body when you lift. The weight limit is a function of various characteristics of the task. We've developed the equation so that companies can take measurements and put them into the equation and come up with a recommended weight limit." Companies interested in starting their own ergonomics programs can examine injury data and locations when working with the equation. "The results can help them determine if they need a lift or an automated rotating mechanism," he says. Information about how to order the equation manual is available via the Internet at: http://www.cdc.gov/niosh/lifting1.html NIOSH is making the Applications Manual for the Revised NIOSH Lifting Equation available from the National Technical Information Service (NTIS). To place an order, call the NTIS Sales Desk at 800-553-6847 and quote order number PB94-176930LJM. The price is $12.00 plus a $4.00 handling fee. Delivery is by first class mail or equivalent. |