Friction-free linear movement in a harsh working environment

HepcoMotionvisit website


Without the development and fabrication work undertaken by the Norwich subcontracting company, F. W. Frost (Engineers) Limited, the accurate assembly of most uPVC doors could not be assured. Its sash centraliser system is a manufacturing fixture that allows the door to be mounted within the frame very accurately, ensuring that the lock and handle mechanism on the door will operate efficiently and the threshold clearance will be correct.

Friction-free linear movement in a harsh working environmentF. W. Frost initially developed this concept for a leading UK uPVC manufacturer, but now its sash centraliser has largely become an industry standard with each fixture being tailor made to the different specification of each manufacturer. But a common feature of each of these innovative fixtures has been HepcoMotion linear motion products.

HepcoMotion LBG linear ball guides are responsible for carrying the two symmetrically opposed sliding frames of the centraliser, maintaining their co-ordination throughout the range of motion. They provide low-friction movement, an important feature as the frames are manually positioned.

The three arms that position the central clamping units are supported by a HepcoMotion UtiliTrak guide and the system also uses HepcoMotion Pacific Bearings. These provide low friction guidance to pneumatically operated lifts that elevate the door from its frame to allow the fitting of hinges.

To support and guide the multiple clamp heads, positioned along the length of the centraliser to clamp the frame and the sash independently, F. W. Frost specified HepcoMotion GV3 single edge linear slides.

Tony Bayliss, the company’s Sales Manager, explains: “The performance of these slides really stands out for this application as they provide a very smooth and reliable solution. The centraliser is a manually operated piece of equipment that is used repetitively, so smooth and easy movement is vital to the prevent operator fatigue.”

Another factor governing F. W. Frost’s selection of the HepcoMotion GV3 system is its ability to provide consistent and reliable operation in harsh manufacturing environments. The V-principle that is the trademark of the HepcoMotion linear motion concept is a key factor in this regard as it provides an effective self-cleaning action.

Smooth movement

Swarf from drilled mounting holes and fasteners that have been misplaced are characteristic of the sash centraliser’s working environment. So the ability of the HepcoMotion GV3 to prevent the ingress of debris onto the contact faces is vital to smooth movement and the system’s suitability for use in a high-production environment.

HepcoMotion GV3 is a proven system for tough environments. Its all-steel slideway is three times stiffer than composite aluminium systems. Low-friction movement helps to lower energy consumption and long re-lubrication intervals cut maintenance costs. And thanks to its adjustable eccentric bearings, GV3 will also continue to work even when worn; other systems would have to be replaced.

Superior surface finish also plays an important part in the performance of the GV3 system. Quite simply, the better the finish, the less likelihood of surface corrosion, and for this purpose HepcoMotion has invested heavily in manufacturing technology to give its products this competitive edge.

Tony Bayliss adds: “We didn’t need to consider any other linear motion supplier for this project as we had used HepcoMotion components on previous equipment with great success. The quality of its products is excellent and they are supported by very good technical staff. We could also source all that we needed from a single supplier.”

Proof of the importance of the F. W. Frost sash centraliser to uPVC manufacturers is the ongoing demands for variants of the system. For example, the company has now developed a version for hanging composite doors. All have been designed to meet the needs for continuous manufacture and minimum downtime. The fit-and-forget quality of the HepcoMotion components has proven to be an important contributor to this performance.

For further information about HepcoMotion’s GV3 system and other products, please visit their website at

© Copyright 2006-14 The Engineering Network Ltd.