Polyurethane Bushes (P.U. Bushes) are the latest substitute to the conventional metallic springs and rubber bushes that are used in sheet metal press tools.
ADVANTAGES OF POLYURETHANE (P.U.) BUSHES:
1. The greatest advantage of using the P.U. bushes is no hunting for the springs. While
designing the press tools one has to design the springs and later on getting small
quantity of particular springs is difficult and calls for lead period to get the same
manufactured. However, P.U. bushes are supplied in the form of tubes and rods of 300 mm length in different diameters ranging from dia 10 to dia 100mm, which can be held in stock.
The lengths of required diameters can be cut and used as and when required.
2. It offers safety under working conditions. The sudden breakage of the metallic springs
can cause the damage to the expensive press tools, which does not happen in case of P.U.
3. It offers more pressures in restricted space where metallic springs cannot give the
4. The bushes offer more pressures than the metallic springs of the same diameter as a
result you have to use lesser number of bushes than the number of springs, thereby
reducing the sizes of the press tools and the costs as well.
5. P.U. bushes are shock absorbent which reduces the air noise.
GRADES AND HARDNESS OF P.U. BUSHES:
1. The bushes, tubes and rods are supplied in two different grades - 30% (green) and 40% (yellow) compressions maximum.
2. Normally we stock tubes and rods of both the grades having Shore hardness 90A. For high pressure requirements we can offer Shore hardness of 95A for specific applications, however increasing the hardness will reduce the compression limit. The supplies can be made against orders.