Maintaining the parallelism of rolls is essential for optimizing the efficiency of your roll machinery. Rolls that are well aligned improve product quality and increase productivity through higher machine availability and production output. The parallelism of rolls is especially critical when machines are running at high speeds or when rolls are in close proximity.
Yokohama Tire Manufacturing Mississippi, LLC (YTMM) a subsidiary of Tokyo-based Yokohama Rubber Co., has been the world leader in the development of outstanding tire designs and technology for more than a century. Company leaders understand the value of roll alignment and incorporate it into the international tire manufacturer’s maintenance strategy.
Proper alignment of rolls on a tire line reduces the possibility of unwanted problems related to poor tracking, uneven web tension, and product defects. Misalignment can arise from settling foundations, everyday wear and tear, and roll change-outs or significant overhauls.
YTMM employs roll alignment in the calendering process at its one-million-square-foot facility in West Point, Miss. Calendering in tire manufacturing is where the steel or fabric of each tire is coated with rubber.
A service team from the Prüftechnik division of Fluke Reliability makes regular visits to the plant to measure each roll in the calendaring process with the ParAlign technology to ensure precision alignment within the desired tolerance.
In the most recent service visit by the Fluke Reliability team, the ParAlign technology measured 104 rolls in less than 10 hours. Also, in that same timeframe, several rolls were adjusted by in-house mechanics and remeasured with the ParAlign. The adjustments were made with the help of precision shims.
How the Technology Works
The ParAlign device operates as an inertial measuring system, using three ring-laser gyroscopes positioned in the x, y, and z axes to measure the angular velocity in each direction, respectively.
The gyroscopes, often used in military aircraft and spacecraft applications, measure the roll, pitch, and yaw of the ParAlign device as it is swept across the circumference of each roll. A minimum of 20 degrees of sweep is needed to measure the center axis of the roll; a line-of-sight isn’t required to measure rolls with the ParAlign.
As points are collected along the arc, the corresponding software equates an angle through geometrical equations. It utilizes the length from bearing to bearing of each roll to determine the horizontal and vertical offsets.
The graphical, easy-to-interpret reporting format allows mechanics to quickly understand what adjustments need to be made and allow for proper corrections with precision shims and dial indicators. Each roll takes roughly 30 seconds to measure, which enables entire machines to be regulated in less than a single day.
Sample report above
Summary
It is critical to the quality of the tires and the life of the machine components to align the rolls in calendering lines.
Inspecting a machine to target a problem, like tracking, must be done efficiently and reliably to keep the machine online and producing goods. Uptime and reliability are byproducts of regularly checking the parallelism of rolls.
YTMM routinely schedules ParAlign visits to maximize the performance of its machinery and ensure its final product meets customer expectations.
Chelsea Fiegel is a Prüftechnik Sales and Application Engineer for Fluke Reliability.