Torsion Bushes

A wide range of standard versions is available providing characteristics to suit diverse applications. They are commonly used in automotive applications for suspension system linkages or leaf spring mounting, where some degree of movement is desirable.  This bush design provides for displacement in a combination of radial, axial, torsional or conical loadings (see diagrams below)



Bushes are placed at the pivot points for any of the following reasons:

• Smooth and predictable movement without the wear associated with solid metal bushes. No surface to surface sliding motion for any required motion.
• Vibration isolation - rubber bushes reduce road noise in automotive applications whilst absorbing impact loads.
• Deflection under load - when engineered into a system, this deflection can allow the linkage freedom of movement.  If deflection is not accommodated within the torsion bush, stresses may be transferred to other mechanical components.
• Modern suspension systems are designed so that the bush deflection does not seriously impact alignment, allowing for vibration isolation whilst maintaining the steering geometry.


Torsion Bush Type: BB
Torsion Bush Type: TB
Torsion Bush Type: B
Torsion Bush Type: BP
Torsion Bush Type: BE
Torsion Bush Type: SAB
Steering Column Bushes
Loading Methods
Typical Application: Automotive Suspension
Polyurethane Bushes

 

Torsion Bush Type BB (double bonded) 

This bush comprises inner & outer tubes in which the rubber is chemically bonded to both tubes allowing applications requiring loading in all possible directions and combinations

With the addition of an intermediate tube which is again chemically bonded in place during the moulding & vulcanisation process. This type of bush is suitable for the highest loads.

Standard TB Type Bushes Part No A Inner Tube I/D B Inner tube length C Outer tube O/D D Outer tube length TB1308 15.69 -15.55 48.43 - 48.13 51.45 - 51.30 38.15 - 37.85 TB1309 19.01 - 18.87 54.25 - 53.95 41.89 - 41.75 38.15 - 37.85 TB1317 15.69 - 15.55 54.93 - 54.67 50.93 - 50.80 44.55 - 44.25

 Torsion Bush Type B 

This type of bush embodies both chemical bond (inner tube only) and interference fit. The interference fit provides for pre-stressing of the rubber making it stiffer for normal radial, conical and torsional loads. It is not intended for use in high axial loading situations. 

One advantage of this bush type is that occasional extreme torsional overloads can be accommodated since the bush will slip within the outer tube under these conditions

Torsion Bush Type BP 

Higher radial and conical loads can be accommodated than with the standard B type bush. 
The ends of the outer tube are permanently deformed after assembly to provide higher axial loading possibilities compared to the B type bush whilst maintaining similar torsional loading performance. 

Torsion Bush Type BE 

Employing both chemical bond (inner tube only) and interference fit as for the B type bush, this version has a chemical bond for the full length of the inner and tube and a specially shaped rubber section designed to prevent metal to metal contact under axial overloads.

Torsion Bush Type SAB 

This bush type is designed for use where a machined housing is available and hence no outer tube is provided.An interference fit provides the required pre-compression as for the B type bush. This construction is intended for only light axial loads.

Loading Methods 

The degree of displacement for a 2 tube system and based on a constant elastomer can be designed-in by adjusting the basic parameters of length plus inner and outer tube diameters as follows:

Radial
This relates to displacement such that the inner tube is moved towards the outer tube whilst remaining axially parallel to it such that the thickness of rubber is reduced uniformly on one side. The radial displacement can be decreased by increasing the projected area (diameter of inner tube x length of outer tube).  This can be facilitated by increasing the overall length of t