Many decades of experience with wheels and rollers, development of application-suitable solutions
RÄDER WENDT GmbH offers a wide variety of wheels and rollers. However, the current bestsellers are the coloured transport rollers made of ABS / PP plastic. They are suitable for crates and boxes (600 x 400 mm) with all-plastic and galvanised steel enclosures. The ABS version was tested by DEKRA for light to heavy loads. All variants are expressly suitable for the food industry and are easy to clean. A maintenance- free product, “Made in Europe”.
Wheels and rollers since 1994
RÄDER WENDT GmbH was founded by Uwe Wendt in 1994. As the managing director in the second generation, Stefan Wendt can fall back on decades of experience with wheels and rollers, experience that benefits both regional as well as national customers in the development of solutions that are tailor-made for the respective application. The warehouse in the industrial area “Tornesch” stores several 10,000 wheels and rollers for customers for immediate delivery. WENDT manufactures wheels and rollers with a lifting capacity ranging from 10 kg to 46,000 kg.
Tyres
The tyres are of crucial importance when selecting the right wheel or roller, because the loading capacity and rolling resistance depend on it. For this reason, the wheels and rollers in WENDT’s catalogue are structured according to the tyres as a main criterion. Significant characteristics of the different tyres are also shown. As an important decision-making aid, the wheel diameter and the loading capacity are in each case specified accordingly.
Loading capacity and optimal smooth running behaviour
There is the matching bearing for each wheel and each roller. LFD ball bearings are therefore designed according to both German as well as international standards and in regard to the most effective use of a specific application.
The customer specifies the framework conditions and is accompanied by the engineers of the LFD Group in regard to the interaction of components up to the optimal product. LFD has developed a specific PX design for ball bearings, which ensure the guide accuracy with low-friction wheels.
Due to the optimal construction selection of the ring geometries and the available rolling elements, it is achieved that the deep groove ball bearings produced in accordance with the PX design only allow extremely small tilt angles and as a result a wheel runs with high guide stability.
The requirements are especially high with manufacturers of nursing and hospital bed rollers as well as on medical equipment:
Because in addition to high corrosion protection requirements, specific requirements are also set in regard to the smooth running behaviour. These wheels are usually made using deep groove ball bearings encapsulated in plastic.
The areas of application of these specific precision rollers with PX design bearings are widely dispersed: In addition to hospital beds, they are utilised in shopping trolleys, wheelchairs, prams, warehouse carts, office furniture, office chairs, furniture in general, in luggage transport and many other applications.
Quality of the routes
The quality of the routes determines the tyre quality and the wheel diameter. For example, with uneven floors it is advisable to select an elastic tyre with a large diameter. The material of the wheel and roller is determined by environmental influences. In the event that the catalogue table does not provide any statements on the resistance against temperatures, chemicals, etc., accurate information should be obtained from the factory.
Loading capacity
WENDT recommends utilising the following formula for the determination of the loading capacity of the selected wheel assembly: Total weight of the unit (= own weight + payload) divided by 3, as often with uneven floors only three of the four wheels make contact. Additionally, when moving over obstacles, overloading can briefly occur. The loading capacities specified in the catalogue for wheels and rollers are valid for vehicle speeds of up to 4 km/h on level, smooth floors (when running in a straight line) with an ambient temperature of 10° C to 30 °C.
The usage type as well as the duration of wheel and roller determine the selection of the bearing. The following distinction must be made with wheel bearings:
Sliding bearing
They offer a simple, largely maintenance-free and shock-resistant bearing. No additional bearing bushings are used with wheels made of polyamide or cast material, as these materials already have good anti- frictional properties.
Roller bearings
They offer a robust, resistant, largely maintenance-free bearing, are the most commonly used bearings for equipment with low speed and have a low rolling resistance.
LFD deep groove ball bearings offer smooth running even with larger loads and speeds for continuous operation. Deep groove ball bearings are mainly used in technically demanding equipment rollers, LFD taper roller bearings are used in heavy load wheels for high loads and speeds and LFD taper roller bearings are especially suited for the absorption of combined (radial and axial) loads. The bearing of the steering box is oriented in regard to its construction to the loads and requirements of the swivel castors.
A transport roller with three boxes 600 x 400 mm, additionally for example a red PP lattice frame and grey 100 mm rubber wheels, are also available as a transport system in a set. Many colours can be implemented on request.
The high-quality frame is comprised of coloured PP plastic (material: polypropylene, first choice – no reclaim material). The open corners are suited for convenient cleaning and can for example be fitted with four sheet steel swivel castors as well as double ball bearings in the clevis. These are galvanised with a wheel diameter of 100 mm and thermoplastic grey rubber wheels in approx. 85° Shore A hardness. The transport rollers with an internal dimension of approx. 610 x 410 mm are suitable for crates with a size of 600 x 400 mm and a capacity of 65 litres.
The suitable lattice frame is characterised by excellent stability and offers a lifting capacity of 300 kg. The set for example includes three grey closed plastic boxes (euro containers / PP plastic) with the external dimensions of 600 x 400 x 320 mm and interior dimensions of approx. 565 x 365 x 315 mm are already included.
The material is suitable for a temperature range of -20 °C to + 80 °C with a lifting capacity of 40 kg. Simultaneously, it is resistant against mild acids and bases. Two open handles simplify the handling.
Breakaway force and rolling resistance
The breakaway force and the rolling resistance is determined by the force with which a vehicle is moved. These resistance values are dependent on the tyre material, the wheel diameter, the quality of the route, the bearing element and the load. The larger the wheel diameter, the smaller the rolling resistance is. Wheels with polyamide and polyurethane running surfaces achieve the lowest breakaway force and rolling resistance on level floors.
Welded heavy load polyamide rollers
The very diverse portfolio also includes special constructions, such as welded heavy load polyamide rollers. The wheel body is comprised of polyamide with a ball bearing. The running surface is free of grooves with an approx. 70° Shore D hardness and a temperature range of -30 °C to +90 °C. The housing is made of sheet steel, the wheel axle is bolted on. Retainers with double stop are also available.
Heavy load polyurethane wheels
The wheel body is either made of aluminium or cast material, fitted with cast, smooth polyurethane with approx. 95° Shore A hardness and a flexible temperature range of -20 °C to +80 °C. Weight-bearing, sealed LFD ball bearings are installed on both sides.
LFD: clear price advantage
Ball bearings made by LFD are optimised for the respective application and accordingly achieve very high loading and carrying capacity, even under extremely harsh conditions. At the same time, LFD bearings are high-quality products and offer a true alternative with a clear price advantage.
LFD: in-house laboratory and test benches
At the development site in Dortmund, the LFD GROUP has a modern equipped in-house laboratory with high-tech measurement systems at its disposal. Additionally, there are also several service life test benches. There, the same measurement equipment is used as in the in-house production. With this, new developments can be documented quickly and optimizations can be implemented promptly.
WENDT offers flanged rim wheels made of both grey cast iron, steel C45 or of comparable quality and a running surface of approx. 180 to 230 HB.
The running surfaces are precision turned and rise approx. 3° to the axle. Depending on the axle diameter and the lifting capacity, a suitable and sealed LFD ball bearing must be used in accordance with the requirements.
Flanged rim wheels are available on request with a lifting capacity of up to 33,000 kg.
