A Quick Guide to Choosing the Best Linear Motion Product

There is a vast range of linear motion products on the market and it can be difficult to know which product to select. This article discusses the various types of products available according to their rolling element and explores their advantages, disadvantages and limitations. Finally a selection chart clearly lists each product’s characteristics to help with specifying the best linear motion product.

Some of our linear motion products are shown in the table below:

Linear Bearings, Housings, Shafts & Supports Heavy Duty Rollers (NUTR, NUKR, NNTR) Vee Bearings Motion Guidance Systems (Standard & Aluminium)
Miniature Motion Guidance Track Guidance System Combined Roller Bearings Plain Sliding Linear Bearings

What are Linear Motion Products?

 The primary purpose of linear motion products is to move something from one place to another in one direction along a straight line. Usually this is achieved using a bearing with a rolling element. Traditionally this rolling element would be a ball or roller, but these days some linear motion bearings do not incorporate a rolling element and consequently are known as ‘plain’ bearings. These plain bearings are simply plastic or ceramic bushes and are sometimes lined with PTFE or oil impregnated plastic to help reduce the sliding friction. Continue reading

How to use Vee bearings and T-rails

Our Vee bearings and T-rails offer the user a simple way of constructing smooth running linear systems with a high load capacity and, in the case of the stainless steel version, corrosion resistance too. For this example we are selecting the following parts:

4 pcs EV W3X ( Vee Bearings)

2 pcs MB3 (Metric bore Concentric bush)

2 pcs MB3X (Metric bore Eccentric bush)

2 pcs T-3 x 1000mm ( T-3 rails 1 metre long)

The first thing to do is to decide the width of the track and then choose what material the T-rail will be attached to. In this example (see drawing) we have selected a piece of steel or aluminum 50mm wide and 1 metre long. Let’s call this the “support”. The precision of the system is dictated by how accurately this support material is manufactured.

The Rail and Support

Drilling the T-rail is easy. The flats are not hardened, only the tip of the vee, so normal drilling techniques can be used. Our preference is to clamp the T-rail to the support material and to drill pilot holes through the T-rail into the support. This means the centres will match. Double check that the T-rail edges are still parallel. Then drill through holes in the T-rails and drill and tap the support.

Finally bolt the T-rail onto the support. We tend to use dome head machine screws. Make sure the screw heads do not interfere with the carriage or rail edges. Also make sure that the rail edges are parallel.

The Carriage and Bearings

In this example we are making a carriage 150mm x 150mm with 4 no. W3X bearings. So again, select the material, steel or aluminium, for the carriage. The hole centre positions for the bearings (dimension “A” on the drawing) can be calculated as:

A = Width of support + 2 x TE + 2 x A1

The value for dimension TE can be found here http://www.euro-bearings.com/veerails.htm (TE in this case is 6.35mm).

And the value for dimension A1 can be found here http://www.euro-bearings.com/veesizes.htm (A1 in this case is 19.05mm).

NOTE: Dimension TE is the offset of tip of Vee rail from the support material. A1 is the dimension from centre of bearing to bottom of Vee. In our example this is 50 + (2x 6.35) + ( 2 x 19.05) = hole centres 100.8mm.

The eccentric bush MB3X allows 1.07mm of lateral adjustment.

Drill the holes through the carriage plate at 100.8mm centres (in this case 8.2mm diameter clearance holes for the M8 bolts we will use to secure the bearings).

Insert the concentric bushes into 2 bearings and insert the eccentric bushes into 2 bearings. Firmly secure the concentric bushed bearings to one side of the carriage plate and tighten. Loosely assemble the eccentric bushed bearings to the carriage plate and slide the carriage onto the T-rails. Now adjust the eccentric bushed bearings by feel (or feeler gauge) to achieve the pre-load required. Slide the carriage back & forth to ensure there are no pinch points. It is recommended to use hex cap head bolts and nyloc nuts through each bearing bush.

IMPORTANT: Make sure the outer ring of the bearing is turning on the inner ring of the bearing and NOT on the bush. The bearing should be an interference fit onto the bush.

Multi Purpose Combined Roller Bearings

Combined Roller Bearings were originally designed to be used in forklift truck masts. However, today they are used in a variety of applications (horizontally and vertically) and in a huge range of industries.

The smallest bearing is just 52.5mm in diameter and when used in conjunction with the corresponding steel profile, each bearing offers a load capacity of approximately 550kg. At the top end of the range the largest bearing is 390mm and has a capacity of over 30 tonnes.

The primary benefit of a Combined Roller Bearing over a standard track roller bearing is the integral side thrust roller bearing. This small roller is able to carry lateral loads and ensures free movement of the system.

To make a complete slide you simply need 2 rails and 4 bearings. The bearings can be welded directly to the structure or can be supplied pre-welded to a mounting plate and simply bolted into place. More complex, telescopic systems can be made by using additional rails and bearings to create further stages.

The application examples below show how versatile this sliding system is.

 

euro combined bearings and channels combined roller bearings forklift horizontal cantilever using combined roller bearings
telescopic combined roller bearings and rails telescopic combinaton bearing application i beam combi bearing cantilevered system

Being so versatile, combined roller bearings can be used in many applications including:Please click an image for more details.

  • Lifting & Handling Equipment
  • Offshore Cable & Pipe Laying
  • Specialised Vehicles
  • Packing Machines
  • Furnace Loaders
  • Agricultural Equipment

If you think you might have an application for Combined Roller Bearings, please contact our technical sales team. We have many years of experience and our team includes Engineers and Designers.

Sliding Gardens

When the Landscape Director from N T Killingley contacted us about sliding a planter in and out of a glasshouse at RHS Chatsworth, our Technical Sales team listened to his specification and suggested various options. Their requirement was a system that was simple to install and robust enough to carry the weight of a laden planter, but most importantly would not cost a fortune as the display was temporary.

The combined roller bearing system met this criteria. By using the rails upturned, there was very little set up involved and the bearings and mounting plates were simply bolted to the underside of the planter.

The end result was a system that was discreet and could be operated with very little effort. The display formed part of the “Garden for a Changing Climate” at RHS Chatsworth in June 2017 and featured on BBC’s Gardeners World.

The RHS video of the garden can be viewed here. And the BBC Gardeners World episode can be viewed here (approximately 41 minutes in).

If you need help to specify a linear sliding system, please contact us. We have a team of Engineers & Designers who can guide you through both selecting the most suitable product and specifying the correct size.

Photo courtesy of N T Killingley © 2017

Did you know…?

Combined roller bearings can be used in a huge variety of applications. In the simplest arrangement (4 bearings & 2 rails) they can be used to make a forklift mast (vertically), a telescopic slide (horizontally) or just to slide something from A to B.

combined bearings and rails
Combined Roller Bearings and Mating Steel Profiles (Rails)

The main advantage of a combined roller bearing is the small axial roller that helps to keep the system running parallel and prevent it from jamming or crabbing. The combi bearings come complete with a weldable hub so they can be welded directly to your structure or, for ease of maintenance, they can be purchased pre-welded to a mounting plate. This mounting plate is simply bolted on with 4 bolts.

Used together with the mating steel channels (rails), the combined roller bearings offer a simple and cost effective way to make a heavy duty linear slide system. The smallest bearing diameter is 52mm, and the largest Jumbo bearing is 390mm. The rails are available in both C and H (or I) sections.

What Products are Available?

Standard Range
standard combined roller bearings rails for combi bearings mounting plates for combined bearings flanged clamps for CR rails eccentric adjustable CR bearings
Precision Range Jumbo Range
standard combined roller bearings rails for combi bearings mounting plates for combined bearings flanged clamps for CR rails eccentric adjustable CR bearings

Precision Range: For heavy duty applications requiring high precision, the Precision Combined Roller Bearings offer a reduced clearance between the bearing & the rail and consequently minimise the play in the system. The rail is machined in the web and the bearing diameter is increased to match this, with a tolerance of 0.2mm – 0.4mm.Click on an image to visit the relevant webpage.

Jumbo Range: For ultra heavy duty applications, the Jumbo bearings can offer an affordable solution.

Corrosion Resistance: In some environments (e.g. Offshore) it can be beneficial to use a corrosion resistant system. The Thin Dense Chromium coating withstands salt spray and can considerably improve the operating life. We can offer all of the ranges with coating.

Please visit our website for full details. Datasheets & pdf catalogues are available to download.

Advantages

+ Very heavy load capacities. See Hertzian Pressure for system capability.

+ Side (axial) roller prevents crabbing. Channel (rail) is self supporting in many applications.

+ Easy to engineer, assemble and set up. Low maintenance.

+ Tolerant of dirty / dusty environments.

+ Bearing diameters from 52mm to 390mm.

Applications

– Access Equipment

– Handling Equipment, including forklift trucks & scissor lifts

– Palletising Machines

– Lifts for goods, personnel and wheelchairs

– Paying Out Systems

 

– Agricultural Machinery

– Primary Food Processing Equipment

– Furnace Loading Equipment

– Production Lines

– And lots more…

Why Euro-Bearings Ltd?

– Large UK-based stock of Combined Roller Bearings

– Over 30 years in the industry

– Always speak to Technical Sales

– Fast delivery

– Family business who value their customers

– Ability to offer custom plates or special diameter bearings

Round Shaft Linear Motion Systems

Round Shaft Linear Motion Systems

We supply a large range of components which can be used for assembling a linear motion system using hardened round shaft for a variety of configurations. Some examples are shown in the image above.

Our ball bushings range includes open and closed type bushings, tandem length versions and both square and circular flanged ball bushings. Many types are also available in stainless steel. Other types available include compact and super ball bushings- please see our website to view the complete range.

We supply the hardened & ground shaft (Cf53) and stainless shaft (X90CrMoV18) that these ball bushings should be run on. We can drill and tap the shafts, if required.

The shafts can be supported on end supports or fully supported on our rail supports. These components are all available in aluminium. Our end supports are also available in cast iron (WB55) and stainless steel (WB59) as well as aluminium (WB56 or WB57).

We supply both aluminium and cast iron housings, either as standard or tandem length versions. These are supplied with our standard ball bushings but can also be supplied with our stainless steel ball bushings (KB50 or KB53).

And we also offer both an open type complete system and closed type complete system which comprise of two shafts, one housing and two end supports. There are two different end supports available depending on whether they will be fixed down (with the carriage sliding) or if the housing will be fixed down. These systems can be supplied with stainless shafts and stainless bushings.

Anti-Vibration Products

Anti-Vibration Products

Above is a selection of the metal / rubber anti-vibration mounts that we supply, ranging from small to large bumpers and buffers through to cone mounts and heavy duty machine mounts. More types can be seen on our website here.

Many of these products are available to buy from our online shop.

We can supply a number of sizes of Male-Male Buffers in stainless steel (part number MMSS). And also Female-Female Buffers (part number FFSS).

If you cannot see what you are looking for on our website please email a drawing or a photograph with dimensions.