Hardness & Softness

Hardness & Softness

The property of hardness is easily recognised, but in design it must be specified to achieve a given objective.
Solid rubbers range from 20° to 98° Shore A, where 20° is extremely soft like foam and 98° is as hard as bakelite or nylon. As a reference, the ball of the human thumb is 25°, a Staedtler white rubber eraser 55° and a bath plug 95° Shore A.

Typical Applications

Designers use rubber in its whole range of hardnesses and each application has to be individually considered. Once a mould has been produced, it is relatively easy to make the same part in other colours and hardnesses to suit different functions.

Whatever the hardness required, it may still be necessary for a rubber component to deform in order to seal against an uneven surface or to resist abrasion.

Major Materials

All rubber types can be compounded to cover most of the range of hardnesses.

Examples of Components

Hardness is required in a part designed to grip paper rolls. It must resist abrasion and not distort in operation. Conversely, rubber suckers used to lift paper sacks have to be very soft to conform to the rough and porous surface.

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