Comparisons Of PU Products

Comparisons Of Pu Products

Polyurethanes have definite advantages over plastics, conventional rubber and metals, which make them a better substitute in applications where these materials are normally used.

… vs. Rubber

  • high abrasion resistance
  • high cut, tear resistance
  • superior load bearing
  • thick section molding
  • colorability
  • oil resistance
  • ozone resistance
  • radiation resistance
  • broader hardness range
  • castable nature
  • low pressure tooling

… vs. Metal

  • lightweight
  • noise reduction
  • abrasion resistance
  • less expensive fabrication
  • corrosion resistance
  • resilience
  • impact resistance
  • flexibility
  • easily moldable
  • non-conductive
  • non-sparking

… vs. Plastic

  • high impact resistance
  • elastic memory
  • abrasion resistance
  • noise reduction
  • variable coefficient of friction
  • resilience
  • thick section molding
  • lower cost tooling
  • low temperature resistance
  • cold flow resistance
  • radiation resistance

Some specific properties of Polyurethanes when examined show it to be a more practical choice as compared to those of rubber, metal and plastic.

Abrasion Resistance:

Abrasion Resistance

The outstanding abrasion resistance of Cast polyurethanes has resulted in thousands of successful applications. In laboratory tests as well as in field applications, Cast Polyurethanes show a definite wear advantage over many other materials, The following figure illustrates a comparison of abrasion properties of Polyurethane with rubbers and plastics.

Right side figure illustrates a comparison of abrasion properties of solid polyurethane with rubbers and plastics. In field studies, polyurethanes have outworn rubbers and plastics, as well as steel and ceramics in some applications, by a factor of 8 to 1.

Stress /Strain Properties

Stress /Strain Properties

Some plastics have high modulus and tensile strength but low elongation. Most rubbers , have high elongation but low modulus and tensile strength. Polyurethane elastomers have high modulus, high tensile strength and high elongation. This combination imparts toughness and durability to the part.

Left side figure compares the stress/strain properties of some polyurethanes with those of a few rubber materials.

Compression Properties:

Compression Properties

Cast Polyurethanes have much higher load-bearing capacity than conventional elastomers of similar hardness.

Right side figure is a comparison of the compressive stresses required to cause a 10% deflection with samples of cast polyurethanes and Neoprene rubber. This high load bearing capacity , combined with the superior abrasion and toughness is an important advantage in applications like metal forming die-pads, die springs, Fork lift tires, caster wheels, industrial rolls, etc.

Hardness and Resilience:

Cast Polyurethane elastomers can be compounded in a wide range of hardness from 20A to 75D (soft as a rubber band or as hard as plastic) Special formulations of cast polyurethanes can be made with resilience values as low as 2% or 75%. This is ideal for applications such as springs and shock mounts.

Hardness and Resilience

Member Testimonials

ONGC – Oil and Natural Gas Corporation Limited

"ONGC - Oil and Natural Gas Corporation Limited" - Our complex drilling application where Shaft was eccentric and application was robust & muddy. Replacement was never easy. Mech Spares designed Oil seals resolved difficulty. This gave a complete joy to my maintenance team.
2014-06-08T07:48:57+00:00
“ONGC – Oil and Natural Gas Corporation Limited” – Our complex drilling application where Shaft was eccentric and application was robust & muddy. Replacement was never easy. Mech Spares designed Oil seals resolved difficulty. This gave a complete joy to my maintenance team.

Kuwait National Petroleum Company

"Mr Mohammed Al Duaigy" of (Kuwait National Petroleum Company) : We tried several diaphragms from renown worldwide Rubber manufacturing companies. We found Mech Spares technical know how and product to be of great durability and lasted 3 times more then anticipated. They have accurate understanding of there products.
2014-06-08T07:49:23+00:00
“Mr Mohammed Al Duaigy” of (Kuwait National Petroleum Company) : We tried several diaphragms from renown worldwide Rubber manufacturing companies. We found Mech Spares technical know how and product to be of great durability and lasted 3 times more then anticipated. They have accurate understanding of there products.

McCafferty BM Design Ltd, KENT United Kingdom

"McCafferty BM Design Ltd, KENT United Kingdom" - Most of the O rings manufacturing company suggested to use larger diameter and expensive elastomers. We learnt with Mech Spares that elastomer being weaker compare to metal and alloys and needs appropriate back up for high pressure or high vacuum applications. Further not necessary the most expensive elastomer is the best for all applications. We trust Mr Nilesh chodhari completely for all our O rings designing applications.
2014-06-08T07:50:26+00:00
“McCafferty BM Design Ltd, KENT United Kingdom” – Most of the O rings manufacturing company suggested to use larger diameter and expensive elastomers. We learnt with Mech Spares that elastomer being weaker compare to metal and alloys and needs appropriate back up for high pressure or high vacuum applications. Further not necessary the most expensive View Full →

Bhabha Atomic Research Centre ( BARC )

"Dr. A. Singh" of BARC: The electric Insulation mat manufactured by MECH SPARES as per IS 15624 tested at ERTL and found to withstand 40 Kv and still didn't tear. We have been using since 5 years and still didn't generate any fatigue. They arranged bulk delivery in short period.
2014-06-08T07:16:20+00:00
“Dr. A. Singh” of BARC: The electric Insulation mat manufactured by MECH SPARES as per IS 15624 tested at ERTL and found to withstand 40 Kv and still didn’t tear. We have been using since 5 years and still didn’t generate any fatigue. They arranged bulk delivery in short period.

Tata Steel

"Tata Steel" - One of our old machines started making loud noise and disturbed the entire village. We were compelled to stop the machines which lead to huge production loss. With the help of Mech Spares designed bellows in two part we could retain the lubrication and eliminate the noise.
2014-06-08T07:17:16+00:00
“Tata Steel” – One of our old machines started making loud noise and disturbed the entire village. We were compelled to stop the machines which lead to huge production loss. With the help of Mech Spares designed bellows in two part we could retain the lubrication and eliminate the noise.
View O Ring Reference Chart