Martin Engineering releases external wear liner

“The wear liner is essentially considered a sacrificial layer,” explained Daniel Marshall, product engineer at Martin Engineering. “Removal and replacement used to be a grueling job that could require multiple workers and days of scheduled downtime. Our goals with this design were to significantly cut the installation and service time, while reducing risk and improving safety.” 

The light bulb moment
Previous designs securely welded the wear liner to the inside of the chute, with only the skirt seal located on the outside. The logic behind the conventional design is for the wear liner to protect the skirtboard, which is typically 1/4” sheet metal.  

Instead, Martin Engineering designers came up with the idea of raising the chute work about four inches above the belt, out of the way of the material, then putting the wear liner on the outside. Using this approach, the material still hits the liner and doesn’t damage the chute. 

“It was a real light bulb moment,” said Marshall. “We were surprised that no one had tried it before, as it has some obvious benefits.”

After elevating the chute box above the material flow, a 3/8″ or 1/2″ (0.95 cm or 1.27 cm) thick abrasion-resistant liner plate (AR 400 or 500) is mounted on the outside of the chute, followed by the skirt seal. Mounting brackets with jackscrews provide a tight hold, with precision adjustment of the wear liner to reduce spillage. This system closes the gap between the liner and the sealer, thus eliminating abrasion from trapped material without interfering with existing supports. When accompanied by Martin Double Sided ApronSeal skirting and clamps, the system is designed to form a tight belt seal, delivering outstanding fugitive material control.

Safer replacement and maintenance
The external liner is designed to be installed and adjusted faster and easier than internal liners without the need for a grinder or torch, through the use of special mounting tabs. Clips for bolting the liner are initially welded in place, but do not require removal when the liner wears out. Since the work is done from the outside, without any grinding sparks or torch flame, the hazard of explosive dust from tool usage is greatly reduced. Replacement liners come in a standard length of 72 inches (1829 mm), and Martin Engineering uses laser cutting technology to create the complex geometries necessary for a custom fit.  

“After decades of using the traditional system, the old procedure just became accepted as the cost of doing business, but we felt there had to be a better way,” Marshall said. “External placement has eliminated many of the safety and maintenance issues surrounding previous designs.”

The new liner is easily retrofitted onto existing equipment using the EVO External Wear Liner Retrofit Kit. Installers simply cut back the chute wall on existing chute boxes to accommodate the external wear liner. On new installations, the chute is easily engineered to work with the new liner design, as well as other Martin Engineering components such as dust curtains, track-mounted idlers and cradles.

Founded in 1944, Martin Engineering is a world leader in making bulk materials handling cleaner, safer and more productive.  The company supplies flow aids and conveyor products around the world for a wide variety of bulk material applications, including coal, cement / clinker, rock / aggregate, biomass, grain, pharmaceuticals, food and other materials. The firm is headquartered in Neponset, IL, offering manufacturing, sales and service from factory-owned business units in Brazil, China, France, Germany, Indonesia, Mexico, South Africa, Turkey, India and the UK, with licensees in Canada, Australia and Chile.  For more information, visit www.martin-eng.com or call (309) 852-2384.  Global representatives for Martin Engineering can be found at www.martin-eng.com/rep-finder.