High duty cycle, low maintenance requirements, very dusty environment - the performance requirements for a linear guide are not exactly mundane given the boundary conditions at Griffith Textile Machine. With its own machinery, Griffith produces more than 250,000 square meters of carpet per year. One of these machines, the Griffith Fast Ax 2 high-speed carpet weaving machine, uses GV3 linear guides from Hepco. This four-meter-wide machine produces high-quality Axminster carpets. It is fully computer controlled and can use up to twelve wool colors in the carpet surface with an endless pattern repeat. This loom produces carpets at three times the speed of previous machines: 700 square meters of carpet in 24 hours.

The Fast Ax2 is equipped with a jacquard pattern mechanism that allows the individual selection and lifting of different colored wool threads to create various patterns and designs. The jacquard, which selects the colors, runs horizontally on the GV3 guide rails. Eight double-sided, reinforced rails are arranged evenly along the four-meter machine. 16 carriages with bearing covers (two carriages per rail) are mounted directly on the machine. Connected to a motor-driven shaft, the GV3 carriages are used here to feed the jacquard back and forth 130 millimeters and select the desired color yarn. This cycle is repeated every 0.5 seconds and the colors are selected according to the pattern.

Carpet weaving generates a considerable amount of dust and fabric fibers that can cause mechanical damage. If dirt particles get into the seals or damage them, the system blocks. GV3 is suitable for this harsh environment thanks to its V-guide system, which is based on tight geometric control of matching V-guides of rails and bearings. The self-cleaning effect prevents contamination of the rail. Proof of the robust design of GV3 is that the Fast Ax2 has been in use for ten years and the bearings have never been replaced. A fundamental requirement for this application is to ensure accurate and repeatable guidance. The Jacquard must move freely and repeatedly to the correct position. Any vertical or rotational play in the bearings would result in a change in height, which would lead directly to a loss of quality in the carpet. With its precision-ground running surfaces, GV3 is a low-friction and high-precision system that is suitable for uniform positioning of the jacquard. Speed is also an important factor: the jacquard moves 130 millimeters in 0.5 seconds and must be moved constantly. GV3 runs smoothly without any change in speed thanks to its balancing capability, which enables it to run evenly over the entire length and achieve high precision.

A key point with V-guide technology is that only minimal lubrication is required to prevent wear on the rail - in some cases it can even run dry. pb