TECHNICAL SUPPORT - GASKETS

Development and production of components for machine tools since 1949.

Classification - Gaskets

VAJ gaskets are made to order, designed to meet specific application needs in sectors such as hydraulics, pneumatics, food, chemical and automotive. We offer customized solutions for:

Static gaskets: for sealing between fixed surfaces
Dynamic seals: for applications with rotary or translational movements
Special gaskets: designed for extreme conditions of temperature, pressure or chemical exposure

Thanks to our experience and production flexibility, we can produce gaskets in a wide range of materials, shapes and sizes, even for small series or prototypes.

Material and thermal compatibility - Gaskets

The choice of material is fundamental to guarantee the durability and effectiveness of the gasket. Below is a comparative table of the main materials used:

Material	Typical chemical resistance	Temperature range
NBR Nitrile Rubber	Mineral oils, greases, light fuels	-30°C / +100°C
EPDM	Hot water, steam, atmospheric agents, UV	-40°C / +140°C
Neoprene	Moderate oils, atmospheric agents	-35°C / +110°C
Silicone	High temperatures, sterilization, food	-60°C / +200°C
FKM (Viton®)	Oils, solvents, fuels, aggressive chemical agents	-20°C / +210°C
Natural rubber	Abrasion, flexibility, air resistance	-40°C / +80°C

Assembly - Gaskets

To ensure an effective and long-lasting seal:

Make sure the contact surfaces are clean and free from imperfections
Check that the gasket is correctly positioned and does not undergo torsion or deformation during assembly
Apply compatible lubricants if necessary to facilitate installation and prevent damage
In dynamic applications, consider the use of guidance or support systems to reduce wear

Troubleshooting - Gaskets

Problem	Possible cause	Recommended action
Loss of seal	Damaged or worn gasket	Replace the gasket and check the operating conditions
Break or tear	Incorrect installation or unsuitable material	Review the assembly process and select a compatible material
Swelling	Chemical incompatibility	Check the compatibility between the gasket material and the fluids used
Hardening or cracks	Aging of the material or exposure to extreme temperatures	Replace the gasket and consider materials with higher thermal resistance

Notes - Gaskets

We offer technical support for the selection of the most suitable material based on specific application needs. Possibility of producing prototypes and small series for preliminary tests and validations.

Dimensional tolerances - ISO 3302-1 - Seals

The ISO 3302-1 standard represents the international reference standard for defining dimensional tolerances rubber products, such as gaskets, seals and moulded parts.

Its objective is to ensure the consistency, reliability, and correct functioning of components, taking into account the specific characteristics of elastomeric materials and production processes.

The directive introduces different tolerance classes (M1, M2, M3 and M4), which allow the most suitable precision level to be defined based on the application, the context of use and the functional requirements of the component. A correct interpretation of classes and tolerances is fundamental to avoid critical issues during assembly, operation and long-term durability.

For this reason, in addition to the regulatory reference, Technical support plays a central roleSupporting the client in reading the standards, choosing the most suitable tolerance class and evaluating technical solutions allows for the reduction of errors, optimisation of the project and assurance of reliable performance.

Below are the main differences between tolerance classes and the reference table, useful as a technical guide for informed evaluation.

Class M1
It is the class with the most restrictive dimensional limits, used when high levels of precision and repeatability are required, typically in technically critical applications.

Class M2
It represents a good compromise between accuracy and production feasibility and is the most used in standard industrial applications, where reliability is required without excessively stringent tolerances.

Class M3
It allows for wider tolerances and is intended for components with less stringent functional requirements, where slight dimensional variations do not affect overall performance.

M4 Class
It is the class with the most permissive tolerances, generally adopted for non-critical or highly deformable elements, for which dimensional accuracy is not a determining factor.

Nominal size (mm)	Tolerance Class M1 (mm)	Tolerance Class M2 (mm)	Tolerance Class M3 (mm)	Tolerance Class M4 (mm)
0.00 - 4.00	± 0.08	± 0.10	± 0.15	± 0.25
4.00 - 6.30	± 0.10	± 0.12	± 0.20	± 0.25
6.30 - 10.00	± 0.10	± 0.15	± 0.20	± 0.30
10.00 - 16.00	± 0.15	± 0.20	± 0.25	± 0.40
16.00 - 25.00	± 0.20	± 0.20	± 0.25	± 0.50
25.00 - 40.00	± 0.20	± 0.25	± 0.35	± 0.60
40.00 - 63.00	± 0.25	± 0.35	± 0.50	± 0.80
63.00 - 100.00	± 0.35	± 0.40	± 0.60	± 1.00
100.00 - 160.00	± 0.40	± 0.50	± 0.70	± 1.30
160.00 -	± 0.30%	± 0.40%	± 0.50%	± 0.70%