Double cradle launch from Martin Engineering

New Evo and Martin slider cradles designed to mitigate conveyor belt wear issues at material transfer points

MARTIN Engineering have launched two new conveyor system components – the Evo slider cradle and Martin slider cradle – designed to mitigate belt wear issues and expensive spillage (due to belt edge sag) at material transfer points.

Located under a skirt board in a chute box after an impact cradle, the units utilize ‘double-life’ slider bars which are said to offer a superior seal with low friction. The result is a flat and stable belt surface throughout the settling zone, reducing fugitive material and extending belt service life.

‘Transfer points can be prone to spillage as the conveyed material lands on the receiving conveyor,’ explained Daniel Marshall, product engineer at Martin Engineering’s US business unit.

‘Once the belt leaves the impact cradle, it can sag while the material is still settling. This compromises the skirt seal, allowing dust and fines to escape, while creating pinch points where material can get caught and gouge the belt.’

Mr Marshall also believes that belt health is a big concern for operators, as edge wear and sagging contribute to misalignment and belt damage which becomes a potential workplace safety hazard.

‘Cradles and impact beds are the foundation of our materials handling strategy,’ he continued. ‘Not only are they on the bottom and everything is built on them, but they offer the flat surface to seal against which is critical in preventing spillage and dust.’

The Evo and Martin slider cradles are designed for conveyor systems with speeds up to 3.5m/s and belts lengths of more than 50ft (15.2m). The cradle units are typically 48in (1.22m) long and available in custom sizes for special applications.

The belt glides over low-friction 62 durometer (shore D) UHMW polyethylene sidebars, featuring the company’s unique ‘box’ design and low drive power consumption. They display minimal heat build-up during operation and can handle service temperatures from –29°C to +60°C. The shape allows operators to turn the bars for a second service life without disassembly of the cradle components.

The bars are available in UHMW plastic or stainless steel. ‘Stainless steel would be suitable for extremely high speeds, or when the conveyed material produces a chemical reaction with UHMW materials,’ said Mr Marshall. ‘The UHMW plastic delivers all the advantages of a firm foundation, without the added power consumption of steel components.’

Centre rollers help reduce friction and energy consumption, and are recommended for applications where capacity is over 450 tons/h. The idlers are optional on single-bar Martin slider cradle designs but standard on all other units.

The Evo slider cradle is attached to its frame on a sliding track, with edge support bars and centre support rollers that slide into position, making it quicker and easier to install and maintain. Manufactured to accommodate belt widths of 36in (915mm) for single-bar models and 42–60in (1,066–1,524 mm) for double-bar designs, operators simply pull the cradle away from the frame to perform maintenance on idlers and sidebars. The cradle can be ordered to suit any CEMA standard trough angle.

The Martin slider cradle features adjustable sidebars to fit any CEMA standard troughing angle, eliminating pinch points where material gets entrapped. The unit is available in sizes ranging from 18–72in (457–1,829mm).

‘Customers who have chosen to install our slider cradles tell us that they notice a considerable reduction in fugitive material around transfer points,’ said Mr Marshall. ‘They have seen less spillage and spent less time on cleaning around moving conveyor equipment, helping to reduce the chance of workplace injuries.’