Stainless Steel Linear Bearings and Guides

Euro-Bearings Ltd stocks a wide range of linear motion products. We are able to offer a variety of products in stainless steel when corrosion resistance is required. Our technical sales team have many years of expertise and are able to guide you with selecting the best product for your application.

Stainless Steel Linear Bearings and Stainless Steel Shafts:

These linear bearings offer high corrosion resistance due to the special characteristics of martensitic stainless steel. The hardening process leads to an increased service life and a higher load capacity.

The linear bearings are available in closed (KB50) and open (KB53) types along with a range of round flanged versions including FK10 (standard length), FK90 (tandem length) and TF00 (centre flanged).

In addition to this, the SK-n super ball bushings and CLBn compact ball bushings are available with electroless nickel coating to the bush and stainless steel balls. Alternatively the LBBRn is a stainless steel linear bearing with compact design.

The X90CrMoV18 stainless steel shafts are hardened and polished linear bearing shafts, and are available from ø3mm to ø50mm. They can be supplied cut to length or machined to your requirements.

Stainless Steel Linear Guide Rails:

The profiled rail linear guides of the motion guidance systems offer high precision and smooth operation.

All of the Miniature Motion Guidance range (sizes 7 to 20) are made from stainless steel as standard.

The Aluminium Motion Guidance range is also corrosion resistant as the raceways and balls are made from stainless steel. It is available in sizes 15, 20 and 25.

Track guidance linear motion

The Track Guidance System can also be supplied as corrosion resistant – the carriages can be supplied with stainless steel bearings and the rails with stainless steel shafts.

Stainless Steel Spline Nuts and Shafts:

The SSP and SPF spline nuts can be supplied in stainless steel with a resin cage, for diameters up to 25mm. The ground spline shaft is available in stainless steel for the corresponding sizes. Other diameters are available with black chrome plating on request.

Stainless Steel Vee Bearings:

When used in conjunction with the Vee rail and Vee bushings, the Vee bearings linear system is suitable for harsh environments with high speed capabilities, medium accuracy and low noise. The Vee bearings, Vee bushes and Vee rails are all available in stainless steel.

Corrosion Resistant Combined Roller Bearings and Rails:

combined roller bearing with TDC coating

For heavy duty linear motion applications, Euro-Bearings Ltd’s Combined Roller Bearings are often the best solution.

The bearings can be Thin Dense Chromium (TDC) coated to provide corrosion resistance and the rails can either be TDC coated for maximum protection, or galvanised / painted. If the rails are galvanised or painted, the surface of the rail in contact with the bearing must remain free of coating to preventing flaking. The standard combined roller bearings are available from ø52mm to ø149mm, with sizes up to ø390mm in the Jumbo range. The rails are available in C or I sections and are cut to the required length.

The bearings and rails can be configured for vertical, horizontal or cantilevered applications and can be used to make telescopic arrangements too. Example arrangements can be found on our website. This system is particularly tolerant of dirt as the bearings are sealed.

Conclusion:

With a wide range of corrosion resistant linear bearings to choose from, you can be certain to find something suitable for your linear motion application. Our technical sales are always happy to help, so please call or email to discuss.

Corrosion Resistant Linear Motion

combined roller bearing with TDC coating

In some applications, it is necessary to specify corrosion resistant products (e.g. food, drink & pharmaceuticals) while in other applications it may be desirable but not essential (e.g. offshore, external use). While a few linear motion products are available in stainless steel, there are often high prices, long lead times & lower load capacities associated with specifying stainless steel.

So what options are there?

For light duty applications there are a few options available in stainless steel. For example miniature motion guidance, round shaft linear products and track guidance systems.

For heavy duty applications there is little choice but some products can be made corrosion resistant by the use of coatings. The most effective coating for linear motion systems is Thin Dense Chromium (TDC). TDC coating provides a hard finish which is able to withstand the high contact load between the bearing and its corresponding track.

Which Products are available?

Euro-Bearings Ltd can offer Combined Roller Bearings with TDC coating to provide a heavy duty corrosion resistant linear motion system. The bearings retain their load capacities (unlike stainless steel alternatives) and maintenance and downtime can be reduced. The TDC coating can also be applied to the rails (channel) and flanged clamps if desired. The combined roller bearings offer a versatile linear motion system which can be used in horizontal, vertical or cantilevered applications.

Euro-Bearings Ltd’s Combined Roller Bearings & Rails with TDC corrosion resistant coating

Another linear motion system to benefit from TDC coating is Vee bearings. While the Vee bearings themselves can be supplied in stainless steel, the T rail to suit the bearings is not so readily available due to the high costs associated with stainless steel. The rails can be TDC coated after any necessary fabrication work and the lead time can be as little as two weeks.

What should I choose?

Every linear motion application should be assessed individually. Use our flow chart to help select which product might be suitable, or ask our technical sales team for advice.

If corrosion resistance is required then consider the following products:

Light to medium duty –
Miniature Motion Guidance (Stainless steel)
Linear bearings & shafts (Stainless steel)
Track Guidance System (Stainless steel)
Exterior Slide System (Aluminium & Delrin)
Vee Bearings & Rails (Stainless steel or TDC coated)

Heavy duty –
Combined Roller Bearings (TDC coated) & Channel (TDC coated or Stainless steel)
Linear bearings & shafts (Stainless steel – small range & lead times are likely to be long)

Summary

Traditionally, corrosion resistance of linear motion products has been provided in the form of stainless steel. However, today, coatings such as Thin Dense Chromium can provide corrosion resistance to bearings without compromising on load capacities and incurring long lead times.

Range of Products to Buy Online

Euro-Bearings Ltd’s online shop has been revamped to be more user friendly. It offers wide range of Linear Bearings, Vee Bearings, Anti-Vibration Mounts & Combined Roller Bearings, all of which are available to buy online. Our technical sales team are on hand should you need any help with selecting the right product.

image of Euro-Bearings Ltd's online shop
Euro-Bearings Ltd’s new e-commerce website offering a wide range of products including Anti-Vibration Mounts, Linear Bearings and Linear Housings, Vee Bearings and Vee Rails, and Combined Roller Bearings and their corresponding Steel Profiles.

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.

Euro-Vee Bearings

euro-vee

EURO-VEE BEARINGS

Our Euro-Vee Bearings are available in 4 sizes which can take radial loads from 100kg up to 800kg. A cost effective linear sliding system can be built using our corresponding T Rail and Euro-Vee Bushings for applications requiring either vertical or horizontal movement.

The bearings are sealed and lubricated for life and so will tolerate being used in dirty environments. The Vee Bushings are used to mount these bearings. We have both concentric and eccentric bushings on stock, in both imperial and metric sizes.

A typical system would use a pair of rails with a minimum of four bearings acting as wheels for a carriage. Half the number of bearings would be mounted on the concentric bushings and the other half mounted on the eccentric type. All the bearings are held in position on their bushings by a bolt fixed through the centre of the bushing. By rotating the eccentric bushings it is possible to tighten the bearings onto (or off) the track. The eccentric bushings have a hex head so that they can be rotated with a spanner before their fixing bolts are tightened back up. The system should be designed so that the main loads are taken by the bearings on the concentric bushings.

The T Rail can either be drilled and bolted down (to a square edge) or it can be welded into position. The body of the rail is soft so it can be easily drilled. The top edge of the rail (where the bearing runs) is induction hardened and polished.

It is also worthing knowing that our Euro-Vee Bearings can be run on round (hardened and ground) linear shaft.

Example applications include:

  • packaging machinery
  • laboratory automation
  • woodworking machinery
  • vending machines
  • sliding doors (eg machine tool doors)

Our Euro-Vee Bearings are also available in stainless steel.