Full thickness
bearing protection
Low friction, long life
Design
Guidelines
Operating parameters for Vesconite
Chemical resistance
Bush sizes
Hard wearing Vesconite is the answer for thin walled bushes. Vesconite has proved itself worldwide as the long life, low maintenance, low friction bushing material.
Traditionally, thin wall bushes have been produced by coating metal strips with a thin lay of low friction polymer - often incorporating lead. This bearing layer is typically between 0,05 and 0,5 mm ( 0.002" and 0.02") thick. These bushes are reasonably effective when operating in perfectly clean environments. See Figure 1 for an example of a bush and shaft at the initial stage of operation.
Unfortunately, ideal conditions - such as a clean environment - are the exception rather than the rule. In the presence of dirt, the thin polymer layer on the metal strip is quickly worn away. This results in metal to metal contact and scoring of the shaft as shown in Figure 2.
Most important is that the full thickness of the bearing is made of Vesconite and not merely a thin layer as is the case with polymer coated metal strip bearings.
Vesconite bearings therefore function as a low friction bearings for their full thickness. Metal to metal contact is avoided, resulting in longer life and no damage to shafts, pins and housings.
Vesconite MV bushes are designed to operate with high loads at low speeds with or without lubrication in dry, wet or dirty conditions. Vesconite is a superior low friction, long life material; harder wearing than acetal and PTFE; and has excellent resistance to solvents, acids and petroleum products (see Chemical Resistance Table).
Vesconite also does not conduct electricity and does not corrode, and therefore will avoid problems caused by electrolytic corrosion.
In comparison to other polymers, Vesconite absorbs very little water. This means that clearances and design loadings are maintained in wet applications or in humid conditions.
Vesconite MV bushes are fully machineable and designed for an interference fit. This means that a firm shaft fit can be achieved.
The thin wall also allows the bearing to form part of a compact shaft design.
Long life, low friction Vesconite MV bushes are your alternative to polymer coated metal strip bearings
Design
Guidelines
PV Calculations:
Calculate the PV (loading x relative surface speed) for the best possible
design.
| PV limits [MPa.m.min-1] | |
| PV | Lubrication |
| <5 | No lubrication required. |
| <10 | Initial lubrication required |
| <25 | Regular lubrication required |
| <200 | Continuous oil or water lubrication required |
| Where: | |
| P = | Load (kg) x 9.81 (m/s²) |
| Shaft diameter d(m) x bearing length (m) | |
| V = | RPM x d(m) x p |
Standard sizes available in stock
| Tolerances | |
| d = Shaft diameter | d: +0.12/+0.17 mm |
| D = Housing diameter | D: +0.05/+0.10 mm |
| L = Length | L: +0/-0.3 mm |
| d | D | Lengths (L) - all sizes in mm | |||||||||||||||
| 10 | 12 | 5 | 8 | 10 | 12 | 15 | 20 | ||||||||||
| 12 | 14 | 5 | 8 | 10 | 12 | 15 | 20 | 25 | |||||||||
| 14 | 16 | 5 | 8 | 10 | 12 | 15 | 20 | 25 | |||||||||
| 15 | 17 | 10 | 12 | 15 | 20 | 25 | |||||||||||
| 16 | 18 | 10 | 12 | 15 | 20 | 25 | 30 | ||||||||||
| 18 | 20 | 15 | 20 | 25 | |||||||||||||
| 20 | 23 | 10 | 15 | 20 | 25 | 30 | |||||||||||
| 22 | 25 | 15 | 20 | 25 | 30 | ||||||||||||
| 24 | 27 | 15 | 20 | 25 | 30 | ||||||||||||
| 25 | 28 | 15 | 20 | 25 | 30 | 40 | 50 | ||||||||||
| 28 | 32 | 15 | 20 | 25 | 30 | ||||||||||||
| 30 | 34 | 15 | 20 | 25 | 30 | 40 | |||||||||||
| 32 | 36 | 20 | 30 | 40 | |||||||||||||
| 35 | 39 | 15 | 20 | 30 | 35 | 40 | 50 | ||||||||||
| 40 | 44 | 20 | 30 | 40 | 50 | ||||||||||||
| 45 | 50 | 20 | 30 | 40 | 45 | 50 | 60 | ||||||||||
| 50 | 55 | 20 | 30 | 40 | 50 | 60 | |||||||||||
| 55 | 60 | 20 | 30 | 40 | 50 | 60 | |||||||||||
| 60 | 65 | 20 | 30 | 40 | 60 | 70 | |||||||||||
| 65 | 70 | 30 | 40 | 50 | 60 | 70 | |||||||||||
| 70 | 75 | 40 | 50 | 70 | |||||||||||||
| 80 | 85 | 40 | 60 | 80 | 100 | ||||||||||||
Sizes in BOLD available ex stock
Other sizes shown, available for minimum order quantity of 10
Sizes not shown available for shafts from 2 to 650 mm
Updated Aug 12 2005
