What does the hardness of IRHD rubber mean? Explanation of the parameters for gaskets and rubber products
The hardness of IRHD rubber is one of the most important parameters used in the design and manufacture of rubber seals, rubber profiles and technical products made of elastomers. The right material hardness has a direct impact on the tightness, durability, deformation resistance and performance properties of the finished product.
In the rubber gasket industry, the IRHD parameter is of great importance, as it allows us to determine how a rubber compound will behave under specific operating conditions.
What is the hardness of IRHD rubber?
IRHD (International Rubber Hardness Degrees) is an international scale for measuring the hardness of rubber and elastomers.
The measurement determines the material's resistance to deformation under pressure from a special indenter. The higher the IRHD value, the material is:
- tougher,
- less prone to deformation,
- more rigid.
Lower values, on the other hand, mean greater flexibility and softness of the material.
Why is rubber hardness so important?
Selecting the right rubber hardness is crucial for proper operation:
- rubber seals,
- rubber profiles,
- mishmash,
- technical seals,
- industrial components.
Too soft a mixture perhaps:
- deform faster,
- lose their tightness,
- be less resistant to stress.
Too hard a rubber, on the other hand, can:
- make installation more difficult,
- deteriorate the fit of the gasket,
- reduce the flexibility of the connection.
Manufacturers of rubber seals therefore select the IRHD parameter individually to the product application.
What are the most commonly used IRHD hardness ranges?
In the manufacture of rubber products, compounds with hardnesses are most commonly used:
- from 40° IRHD,
- up to approximately 80° IRHD.
Soft mixes:
- better adapt to the surface,
- ensure a high degree of watertightness,
- work well at low pressures.
Harder blends:
- are more mechanically resistant,
- better withstand high loads,
- are proven in demanding industrial installations.
IRHD hardness vs. rubber type
The final hardness of the gaskets is influenced not only by the production process itself, but also by the type of rubber used.
The most commonly used materials are:
- EPDM,
- NBR,
- SBR.
EPDM
EPDM compounds are characterised by:
- high weather resistance,
- water resistance,
- resistance to ageing,
- good flexibility.
They are often used in:
- sewer seals,
- water seals,
- external profiles.
IRHD hardness vs. rubber type
How is the hardness of rubber tested?
Hardness measurement is carried out using specialised measuring equipment that complies with quality standards.
In professional production facilities, quality control includes:
- hardness measurement,
- strength test,
- ageing tests,
- deformation tests,
- chemical resistance control,
- analysis of physical and mechanical parameters.
Regular testing helps to maintain:
- repetitive production,
- stability of parameters,
- compliance with industry standards.
IRHD hardness and the use of rubber seals
Choosing the right hardness depends on:
- type of installation,
- operating pressures,
- temperatures,
- chemical environment,
- type of medium,
- customer requirements.
Gaskets with different IRHD parameters are used in, among others:
- sewers,
- waterworks,
- engineering industry,
- construction,
- Agriculture,
- white goods sector,
- industrial installations.
Rubber gasket manufacturer vs. IRHD parameter control
A professional rubber gasket manufacturer should provide:
- quality control of materials,
- stability of parameters,
- compliance with standards,
- proper selection of rubber compounds.
M.O.L. ROMGUM uses its own laboratory equipped with state-of-the-art control and measuring equipment to precisely control the parameters of rubber mixtures and finished products.
Production is carried out in accordance with quality standards and industry requirements for technical seals.
How do you choose the right rubber hardness?
The choice of hardness should take into account:
- operating conditions of the gasket,
- mechanical loads,
- chemical resistance,
- temperature,
- tightness requirements,
- installation type.
When designing technical seals, it is therefore very important to work with an experienced rubber products manufacturer who will help to select the right compound and material parameters.
FAQ
What does IRHD stand for?
IRHD stands for International Rubber Hardness Degrees, an international scale for measuring the hardness of rubber and elastomers.
Why is rubber hardness important?
Hardness affects the tightness, flexibility, mechanical resistance and durability of seals and rubber products.
What are typical rubber hardness values?
The most commonly used rubber compounds have a hardness of 40° to 80° IRHD.
What does a higher IRHD value mean?
The higher the IRHD value, the harder and less deformable the material.
Does the hardness of the rubber affect the tightness of the seal?
Yes, the correct hardness is crucial for the proper function and tightness of the seal.
What materials are used to manufacture rubber seals?
Compounds based on EPDM, NBR and SBR rubbers are the most commonly used.