Linear Shafts and Bearings from Automotion
A linear shaft is a straight, precision machined bar on which linear bearings run to create a linear guide system to support or guide the movement of equipment in a linear fashion. Available in hardened steel, hardened stainless, 303 and 316 stainless, and aluminium. We can also manufacture on short lead times linear shafts to your drawing with custom machining, keyways, circlips grooves, drilled and tapped holes and more.
As specialists in linear motion systems we offer you a choice of materials and sizes. So whether you need lightweight aluminium rails for use in aviation applications or stainless steel components for when exposure to water or corrosive chemicals is a factor, our knowledgable technical engineers are always on hand to provide assistance.
Make sure you download a free Linear Motion Handbook here and utilise our free CAD to help you save time planning your projects.
Linear Shafts
Hardened steel and corrosion resistant steel linear shafting stocked in lengths of 3m.
Aluminium Anodised shaft bars for use with self lubricating ceramic bearings.
Hard stainless steel linear shafts for use with linear bearings.
Soft stainless, high anti-corrosion. Not for use with ball bush linear bearings.
Soft stainless, very high anti-corrosion. Not for use with ball bushing linear bearings.
Linear Bearings
Ceramic closed linear bearings. Made with with aluminium-oxide ceramic coating.
Ceramic bearings are ideal for use on all shaft bar materials.
Stainless linear bearings. For use with corrosion resistant
hardened shafts.
Linear Ball Bushings
For use with hardened shafts only, steel ball retainers can be supplied for higher temperature applications up to 120 ℃.
Low cost, compact. Durable plastic body with corrosion resistant hardened steel raceway segments.
Superball, Linear Ball Bearings, 10mm to 50mm.
Long, circular Flanged Linear Ball Bushings - 6mm to 60mm. Double complement bearings.
Long, square Flanged Linear Ball Bushings - 6mm to 60mm. Double complement bearings.
Linear Carriages
Aluminium body, with linear bearing. For use with hardened shafts only.
Open linear ball busing carriages. Particularly effective for high loads and long stroke applications.
Stainless unflanged carriages. Aluminium carriage housing.
Linear Shaft Support Rails
Hardened steel shafting or corrosion resistant linear shaft rods mounted on aluminium alloy support rails, for use with open flanged or unflanged carriages.
Associated Products
Our popular linear rail systems with either flanged or unflanged carriages, widths 15, 20, 25, 30, 35, 45 and 55mm, and lengths up to 4 metres. Rear-fixing rails or ultra-low profile carriages also available.
Only for horizontal linear translation applications. An affordable easy sliding rail system for heavy duty shorter stroke applications (lengths up to 2 metres).
Linear Shafts Product Selection
Product Selection
L1770 - Hardened steel shafts
For use with linear bearings.
Ø6 to Ø60
L1771 - Hardened hollow shafts
For use with linear bearings. Hollowed for lighter weight.
Ø12 to Ø50
L1772 - Hardened Stainless shafts
For use with linear bearings Anti-corrosion.
Ø6 to Ø60
L1773 - Stainless 303 shafts
Soft stainless, high anti-corrosion.
Not for use with ball bush linear bearings.
Ø6 to Ø60
L1774 - Stainless 316 shafts
Soft stainless, very high anti-corrosion.
Not for use with ball bushing linear bearings.
Ø6 to Ø60
L1778 - Aluminium shafts
Light weight, non-magnetic.
Ø10 to Ø50
Linear Shaft Materials
Materials
Hardened steel linear shafting (L1770 – L1771)
Carbon steel to BS 070M55 hardened to 60-65 HRC. Carbon Steel B.S. 070M55 is a medium carbon steel which is used when greater strength and hardness is desired than in it’s as rolled condition. Extreme size accuracy, straightness and concentricity are combined to minimise wear in high speed applications. Suitable for use with all types of linear bushings.
Corrosion resistant steel (L1772)
440C is a high carbon chromium martensitic stainless steel, generally supplied in the annealed condition with a maximum hardness of 50-55 HRC. Characterised by good corrosion resistance in mild domestic and industrial environments, including fresh water, organic materials, mild acids, various petroleum products, coupled with extreme high strength, hardness and wear resistance when in the hardened and tempered condition. Used for parts requiring a combination of excellent wear resistance, plus reasonable corrosion resistance. Typical applications are: ball bearings and races, bushings, cutlery, chisels, knife blades, pump parts, surgical instruments, valve seats etc. Material magnetic in all conditions. Suitable for use with all types of linear bushings.
Stainless steel AISI 303 (L1773)
303 is a free machining chromium-nickel austenitic stainless steel with good strength and good corrosion resistance, as supplied in the annealed condition. Characterised by excellent machinability and non galling properties due to its higher sulphur content, which has the effect of slightly lowering its corrosion resistance. It is however, fairly resistant to general atmospheric corrosion, general foodstuff s, sterilizing solutions, dyestuffs, most organic chemicals, plus some inorganic chemicals. But has very limited resistance to acids. 303 cannot be hardened by thermal treatment, but strength and hardness can be increased substantially by cold working, with subsequent reduction in ductility. It is used primarily for production runs involving extensive machining, or complex parts requiring excellent machinability. Typical uses are: architectural components, food processing equipment, dairy equipment, dying industry, hardware and kitchenware manufacturing and allied industries. Commonly used to manufacture bolts and nuts, bushes, gears, shafts, valve bodies and fittings etc. Material is non magnetic in the annealed condition, but can become mildly magnetic following heavy cold working. Annealing is required to rectify if necessary.
Not suitable for use with linear ball bushings, please use ceramic bearings.
Stainless steel AISI 303(L1774)
316 is a chromium-nickel-molybdenum austenitic stainless steel with good strength and excellent corrosion resistance, as supplied in the annealed condition. Characterised by high corrosion resistance in marine and industrial atmospheres, it exhibits excellent resistance to chloride attack and against complex sulphur compounds employed in the pulp and paper processing industries. The addition of 2% to 3% of molybdenum increases its resistance to pitting corrosion and improves its creep resistance at elevated temperatures. Also it displays good oxidation resistance at elevated temperatures and has excellent weldability. AISI 316 cannot be hardened by thermal treatment, but strength and hardness can be increased substantially by cold working, with subsequent reduction in ductility. It is used extensively by the marine, chemical, petrochemical, pulp and paper, textile, transport, manufacturing and allied industries. Typical uses are: architectural components, textile equipment, pulp and paper processing equipment, marine equipment and fittings, photographic equipment and x-ray equipment etc. Material non magnetic in the annealed condition, but can become mildly magnetic following heavy cold working. Annealing is required to rectify if necessary.
Note: Optimum corrosion resistance is achieved in the annealed condition. Not suitable for use with linear ball bushings; please use ceramic bearings.
Linear Shafts General Guidance
General Guidance
As well as standard cut to length shafting, Automotion can offer many specials including imperial shafts, different tolerances and non-standard diameters.
We can also machine shafts to your requirements so if you have a specific requirement, please contact our Sales team. Below are examples of just some of the machining we can do to shafting on a quick turnaround.
Linear Ball Bushings General Guidance
General Guidance
Linear ball bushings
Applications
- Computers and peripheral equipment.
- Recording equipment.
- Linear motion systems.
- Multi-axis drilling machine.
- Printing machines.
- Food packaging machines.
- Punching presses.
- Tool grinders.
- Assembly systems.
- Card selectors.
Interchangeability
Our linear bushing systems are designed to have full interchangeability, with other manufacturers’ parts. For shafting see part numbers L1770 to L1785.
High precision retainer
The single body retainer guides 4-6 ball circuits. It precisely guides the balls with a smooth motion.
Tolerance of housing bore
Normal fit is standard, pressed fit is for without clearance.
| Part no. | Normal fit | Pressed fit |
| L1706 to L1733 | H7 | K6, J6 |
| L1706...-1 to L1733...-1 | H7 | J7 |
Rigid outer sleeve
The hardened and precisely ground outer sleeve is made of bearing steel.
L1750 bushing carriages
Consists of light aluminium case and L1706 type linear bushing, so the installation can be finished simply by bolting. Longer life can be obtained by adjusting the orientation of the ball circuits in the linear carriage element against the direction of load.
Tolerance of shaft
| Part no. | Normal fit | Tight fit |
| L1706 to L1733 | h6 | k6 |
| L1706...-1 to L1733...-1 | f6, g6 | h6 |
Basic dynamic load rating C
The basic dynamic load rating is defined as the constant load both in direction and magnitude under which a group of identical linear bushings are individually operated. 90% of the units can travel 50Km without failing due to rolling contact fatigue.
Basic static load rating C0
If a linear bushing is subject to an excessive load or impact, a permanent deformation occurs between the raceway and the rolling element. The basic static load rating is defined as the static load that gives a prescribed constant contact stress at the centre of the contact area between the rolling element and raceway receiving the maximum load.
Superball linear ball bushings
- 3 x the load rating and 27 x the travel life of conventional linear bushings
- Self-aligning feature
Features
Higher load ratings
The uniquely designed ball plate (in the outside diameter of the bushing), is made of hardened steel. The precision ground groove is slightly larger than the ball size, which provides greater contact area between the balls and the ball plate, and as a result, provides 3 x higher load ratings of conventional linear bushings.
Self-alignment
The ball plate has a convex shape to provide a pivot point at the centre which allows self-alignment up to ±0.5°. This self-alignment capability eliminates any possibility of edge pressure caused by inaccurate machining, errors on mounting, or shaft deflection.
Tolerance of shaft and housing bore
| Part no. | Shaft Ø d1 | Tol. h6 μ | Housing bore Ø d2 | Tol. H7 μ |
| L1740.010 | 10 | +0 to - 9 | 19 | +21 to -0 |
| L1740.012 | 12 | +0 to - 11 | 22 | +21 to -0 |
| L1740.016 | 16 | +0 to - 11 | 26 | +21 to -0 |
| L1740.020 | 20 | +0 to - 13 | 32 | +25 to -0 |
| L1740.025 | 25 | +0 to - 13 | 40 | +25 to -0 |
| L1740.030 | 30 | +0 to - 13 | 47 | +25 to -0 |
| L1740.040 | 40 | +0 to - 16 | 62 | +30 to -0 |
| L1740.050 | 50 | +0 to - 16 | 75 | +30 to -0 |
FAQs
Linear Shafts vs Rotary Shafts: What's the difference?
A linear shaft is required when a sliding motion is needed, especially when that motion needs to be fine-tuned and guided. However, if you need to transmit power over a distance, or if you need to change the relative speed of some rotation, a rotary shaft will act as the better solution. Please get in touch with one of our expert technical engineers if you need more advice.
What are Linear Shafts used for?
Linear shafts are a critical component in linear motion machines and applications. Uses can often be found in the aerospace, medical, packaging and industrial sectors, amongst others. Our linear shafts can be manufacture with different diameters, strengths and materials and offer superior support and bearing for different machines and mechanisms.
What are the types of Linear Shafts?
Linear shafts typically come in three types: Solid, hollow, or supported. Solid shafts are available in a range of materials such as steel, stainless steel grades and aluminium. These can be manufactured with male or female threaded ends to aid installion. Hollow shafts are typically used for weight saving or when cables need to be threaded through the centre. Fully support shafts, or shaft support rails, are used when deflection due to loads involved are a concern.
