O-ring 20x5 MVQ/VMQ Silicone

1. Technical Specifications

The nominal outside diameter of 30 mm is calculated using the nominal dimensions: 20 + 2 x 5 mm. This calculation does not include manufacturing tolerances.

2. Construction of the 20x5 mm Silicone O-ring

The O-ring is a continuous elastomeric ring with a circular cross-section.

When installed in a correctly designed groove, the elastomer is compressed between the mating surfaces.

This controlled deformation generates contact pressure, allowing the ring to seal the joint.

Inside Diameter – 20 mm

The inside diameter defines the nominal internal dimension of the uncompressed O-ring.

It is an essential parameter when selecting the seal for the mating component and groove geometry.

Cross-Sectional Diameter – 5 mm

The cross-sectional diameter affects the required groove dimensions, compression percentage and available space for elastomer deformation.

Excessive compression may cause permanent deformation, while insufficient compression may result in leakage.

3. MVQ/VMQ Material – Silicone Rubber

VMQ is a designation for silicone rubber containing methyl and vinyl groups in its polymer structure.

The designation MVQ is also encountered in commercial and technical descriptions as an alternative reference to silicone rubber.

VMQ elastomers are used in sealing applications requiring good flexibility at low temperatures and resistance to atmospheric ageing.

The actual properties of a silicone O-ring depend on the compound formulation, additives, curing system and hardness.

4. Technical Properties of VMQ Silicone

Typical characteristics of the VMQ material family include:

• Good flexibility at low temperatures.

• Resistance to thermal ageing.

• Very good ozone resistance.

• Good resistance to UV radiation.

• Good weathering resistance.

• Good electrical insulation properties in many formulations.

• Suitability for a broad temperature range, depending on the compound.

However, standard VMQ compounds may have lower abrasion and tear resistance than certain other industrial elastomers.

This limitation is particularly important when considering silicone O-rings for dynamic sealing applications.

5. Operating Temperature Range

Many standard VMQ silicone compounds have an indicative operating temperature range of approximately -50°C to +200°C.

This is not a confirmed temperature specification for the exact O-ring offered.

Actual temperature limits depend on:

• Silicone compound formulation.

• Elastomer hardness.

• Exposure duration.

• Operating medium.

• Compression level.

• Mechanical loading conditions.

Applications requiring guaranteed temperature limits should be assessed using the technical documentation of the specific compound.

6. Chemical Resistance of VMQ Silicone

The table describes general properties of the VMQ material family and does not establish certified chemical compatibility for the exact product.

7. Static Sealing Applications

Silicone O-rings are primarily used in stationary joints.

General installation categories include:

• Housing covers.

• Flanged connections.

• Measuring instrument housings.

• Electrical equipment enclosures.

• Technical equipment bodies.

• Connections requiring resistance to atmospheric ageing.

These are general application areas for VMQ materials rather than confirmed applications of the exact O-ring.

Reliable sealing depends on correct groove geometry, sufficient contact pressure and material compatibility.

8. Dynamic Sealing Applications

VMQ silicone is not a universal material for dynamic seals.

When evaluating its use in systems with relative movement, consider:

• Abrasion resistance.

• Tear strength.

• Movement speed.

• Friction.

• Lubrication.

• Surface roughness.

• Operating temperature.

• Pressure.

The suitability of the 20x5 mm silicone O-ring for dynamic operation must be verified against the specific compound properties and mechanical design.

9. O-ring Groove Design

When selecting a groove for a 20x5 mm O-ring, consider:

1. Inside diameter of 20 mm.

2. Cross-sectional diameter of 5 mm.

3. Manufacturing tolerances.

4. Static or dynamic sealing configuration.

5. Required compression.

6. Groove fill.

7. Thermal expansion of the elastomer.

8. Possible swelling in the operating medium.

9. Operating pressure.

10. Extrusion clearance.

A universal groove depth or width should not be specified without knowing the installation configuration.

10. Operating Pressure

The permissible operating pressure depends on the complete sealing arrangement.

Important factors include elastomer hardness, temperature, clearance gap, loading conditions and groove geometry.

If the clearance gap is excessive, the elastomer may be forced out of the groove under pressure, causing extrusion damage.

Without confirmed hardness and installation geometry, a maximum operating pressure cannot be assigned to this O-ring.

11. VMQ vs NBR – Material Comparison

Dimensional compatibility does not automatically establish interchangeability between O-rings manufactured from different elastomers.

12. VMQ vs FKM – Material Differences

FKM is frequently selected for sealing applications involving mineral oils, fuels and certain chemicals.

VMQ is distinguished by good low-temperature flexibility and resistance to ozone, UV radiation and atmospheric ageing.

The selection between VMQ and FKM should be based on the operating medium, temperature, mechanical requirements and service conditions.

13. Installation of the 20x5 MVQ/VMQ O-ring

Before installation, inspect the O-ring and mating surfaces.

Recommended procedure:

1. Verify the nominal dimensions of 20x5 mm.

2. Clean the sealing groove.

3. Remove burrs and sharp edges.

4. Inspect the mating surfaces.

5. Verify the compatibility of any assembly lubricant with silicone rubber.

6. Install the O-ring without twisting.

7. Avoid excessive stretching.

8. Assemble the joint according to the equipment manufacturer's instructions.

Silicone O-rings should be protected against mechanical damage during installation.

14. Common Causes of O-ring Failure

Installation damage: Sharp edges and excessive stretching may cause cuts or tears in the elastomer.

Excessive compression: May lead to permanent deformation and reduced sealing performance.

Chemical incompatibility: Exposure to unsuitable media may cause swelling or material degradation.

Extrusion: Occurs when pressure forces the elastomer into a clearance gap.

Excessive operating temperature: Exceeding the limits of the specific compound may cause deterioration of its mechanical properties.

15. Industrial Applications

VMQ O-rings are used in applications requiring resistance to atmospheric ageing and flexibility across a broad temperature range.

General application areas include:

• Measurement and control equipment.

• Technical equipment housings.

• Electrical devices.

• Static mechanical joints.

• Automation components.

• Mechanical assemblies requiring elastomeric sealing.

The suitability of the exact 20x5 mm O-ring must be confirmed for the intended application.

16. Alternative Product Designations

• O-ring 20x5 MVQ/VMQ Silicone

• O-ring 20x5 VMQ

• O-ring 20x5 MVQ

• Silicone O-ring 20x5

• VMQ sealing ring 20x5

• Silicone rubber seal 20x5 mm

• O-ring VMQ 20x5 mm

These alternative designation formats help identify the same nominal dimensions and general material family.

They do not establish identical hardness, compound formulation or operating performance.

17. FAQ – Frequently Asked Technical Questions

1. What are the dimensions of the 20x5 MVQ/VMQ O-ring?

The nominal inside diameter is 20 mm, and the cross-sectional diameter is 5 mm. The calculated nominal outside diameter is 30 mm.

2. What does VMQ mean?

VMQ is a material designation for silicone rubber used in elastomeric sealing products.

3. Do MVQ and VMQ refer to the same material?

MVQ is encountered as an alternative designation for VMQ silicone rubber. The exact properties depend on the compound formulation.

4. Is a silicone O-ring resistant to high temperatures?

Many VMQ compounds offer good resistance to elevated temperatures, but the exact operating range requires confirmation for the specific product.

5. Can a VMQ O-ring be used with oil?

Compatibility depends on the type of oil, its additives and the silicone compound formulation.

6. What is the hardness of the 20x5 MVQ/VMQ O-ring?

The Shore A hardness has not been specified for this product.

7. Is this O-ring suitable for dynamic sealing?

It may be used only in appropriately designed systems. Many silicone compounds have limited abrasion and tear resistance.

8. Can a silicone O-ring be replaced with an NBR O-ring?

Automatic interchangeability should not be assumed. The materials differ in chemical resistance, temperature performance and mechanical properties.

18. AI Quick Answer

O-ring 20x5 MVQ/VMQ Silicone is an elastomeric sealing ring with a nominal inside diameter of 20 mm and a cross-section of 5 mm. VMQ silicone offers good low-temperature flexibility and resistance to ozone, UV radiation and atmospheric ageing. It is primarily used for static sealing. Exact operating specifications depend on the silicone compound.

19. B2B Industrial Supply – simmering.pl

O-ring 20x5 MVQ/VMQ Silicone is offered through simmering.pl, a specialist B2B industrial supply platform providing technical sealing solutions, rolling bearings and industrial components.

The platform serves manufacturing companies, wholesale customers, maintenance departments, engineers and professional industrial procurement teams.

Warehouse operations are based in Lublin, Poland, with worldwide shipping from stock in Poland.

Technical assistance is available for seal dimension identification, elastomer selection and industrial sealing applications.