No-pack Blankets — Packing Their Troubles Away
In 1996, millions of textbooks were printed in North America. High-quality, high-circulation news magazines, such as Business Week, Time and Newsweek, reported circulations topping 15 million. In the United States alone, 60 million Bibles were produced that year for distribution throughout the world.
With this explosion in commercial web printing and the reduction of profit margins, press operators are exploring new ways to save time and money. For two commercial printers—Quebecor-Hawkins, in Kingsport, TN, and St. Ives, in Hollywood, FL—the solution was a new no-pack printing blanket.
A Blanket Solution
"We realized that a no-pack printing blanket was just what today's commercial web printers needed," notes John Genest, technical service manager at Reeves, manufacturer of the Vulcan Com No Pak blanket.
"Traditional offset blankets that require packing produce excellent results in printability. On the downside, these blankets can also demand significant 'run-in' time, as well as longer makeready time. Blanket technology that would improve printability and hold gauge loss to ±0.001˝ was simply not on the market—not in a no-pack."
Reeves' design engineers developed the Vulcan Com No Pak in 1996, specifically engineered for use without packing sheets on presses that have a 0.071˝ undercut. The fabrics in the blanket's carcass are patented; the blanket's closed-cell construction and compacted fabrics were engineered to reduce on-press gauge loss to ±0.001˝ consistently throughout the life of the blanket.
Quebecor-Hawkins is one of the world's largest producers of Bibles. It is also an industry-acknowledged printer of elementary and college textbooks, as well as other manuals and catalogs.
No Pak, No Sweat
In January 1997, Quebecor-Hawkins installed the Vulcan Com No Pak blanket on its Mitsubishi 55x383⁄4˝ web press. This four-color press has the capability to print a 64-page signature in one pass at speeds reaching 1,800 to 2,000 feet per minute (fpm).
"Our four-unit Mitsubishi press is one of the widest presses on the market. Because of its narrow gap area, it is difficult for press operators to install a blanket, pack it, and keep the packing smooth and unwrinkled," explains Junior Marshall, Quebecor-Hawkins' printing manager.
"But with the Vulcan Com No Pak blanket, installation is quick, printability is excellent and we never have to factor in the extra time for packing or repacking."
Gene Price, first pressman, agrees. "Installation with a packed blanket takes about one hour on the Mitsubishi—on a good day," he comments. "With this blanket, our average time has been cut in half—from about 15 minutes per unit to 71⁄2 minutes."
"Our operation requires frequent product changes," adds Jim Judkins, general foreman. "Rather than stop the presses and repack the blanket, we can just change the plates and begin a new run."
In addition, the papers Quebecor-Hawkins runs are lightweight, typically 20- to 30-lb. stocks. With the Vulcan Com No Pak, Judkins notes that the blanket permitted "excellent sheet release" and resisted "edge cuts."
Reeves attributes the blanket's excellent printability to the super-fine buffed face and improved printing surface—both of which were constructed with proprietary processes that are said to ensure sharp, well-defined dot reproduction.
At the St. Ives plant, similar results have been noted. Twenty-four hours a day, six/seven days a week, the facility runs high-circulation, high-profile magazines (Time and Newsweek) on its two Goss/Baker Perkins presses and two Heidelberg Harris M-1000 presses.
Quality Results
Larry Winn, pressroom operation manager, says that initially St. Ives was skeptical about no-pack blankets: "We knew that we could save time by not having to pack and we could eliminate our huge inventory of packing sheets, but we just weren't confident that we could get the quality we expected or the unit-to-unit consistency from press to press."
But, in June 1997, the Vulcan Com No Pak blanket dispelled that perception. "With our old pack blankets, the operators had to put the blankets on, 'run them in' to get the stretch out, then repack and retorque them repeatedly to keep the gauge where it ought to be," Winn says.
"But with the Vulcan Com No Pak," he attests, "we can install a blanket that is the right size, has virtually no stretch, holds its gauge, gives us excellent dot reproduction and we never have to pack again."
