PU (Polyurethane Die-Springs, Pads & Punch-Strippers)
Polyurethane Die-Springs, Pads & Punch-Strippers are offered as PERFECTHANE in polyether-elastomers that react similarly to an incompressible fluid. The volume of material moved by compression is displaced laterally in the form of bulging sides. An approximation to the change in diameter of one of our standard cylindrical urethane springs can be made by increasing the diameter by the inches of compression.
Polyurethane springs exceed the capacity of coiled springs in generated forces and strokes in a similar space. This is accompanied by the non-compressibility and resiliency.
Its volume remains constant under force but changes shape, similar to a solid fluid with a memory. Under load, PERFECTHANE springs produce a high, uniform and continuous counter pressure, returning to original shape when load is released.
These springs are useful in applications where corrosion, vibration, and magnetism prevent the use of conventional steel springs. Also, urethane springs have proven to be the safest, most efficient and reliable compression material for punching, stamping and drawing dies. As compared to conventional springs, the advantages of the PERFECTHANE material include the following:
Properties
High load-carrying capability
Protection against marring/galling
Abrasion resistance
Oil and solvent resistance
Vibration damping and shock absorbance
No sharpnellizing
Effectiveness between - 30° F and 180° F
High dielectric strength and non-magnetic
Longer life
Corrosion resistant
Low noise
100% load-bearing surface
Bondable to mating parts
Low cost
Solids & Hollow
OD x ID (in mm)
to
OD x ID (in mm)
Rods > Solid
12.7 x 0.0
to
200 x 0.0
Rods > Hollow
20.0 x 8.0
to
200 x 40
Pads & Sheets
Thick (in mm)
Size: L x W (in mm)
Sheets > Square
4-40
300x300, 500x500, 600x600, 1000x1000
Sheets > Flat Strip
4-40
150x150, 300x150, 600x150, 1000x125, 1000x250
Notes
All solid & hollow rods are supplied as mould finish.
All rods are supplied in standard 300 mm lengths. Non-standard lengths are offered on request.
All sizes are supplied with standard tolerances.
Flat Strip Sheets are supplied in a set of four pieces.
Thin sheets < 4 mm and thick sheets > 40 mm are also supplied against order.
Spring grade is offered in standard hardness of 90 + 3 Shore A Hardness.
