The material silicone is a popular material for o rings and due to the variety of types of silicone available is known by several terms. These different terms are defined by the International Organisation for Standardisation (ISO), with each individual silicone material encompassing unique properties and variables.
This means choosing the right silicone seal and gasket for your application is critical.
When it comes to o rings, silicone is often preferred in many sectors, such as the food sector, medical, automotive, and aerospace industry. This is due to the material’s great level of flexibility and low toxicity. Silicone is also oxygen, ozone, and UV resistant, it offers thermal stability, and it also boasts a great temperature range.
In this post, we look at some of the types of silicone o rings, their differences, and the benefits they can bring to specific applications.
MQ, VMQ, PMQ, and FVMQ silicone o rings meaning
Silicone is a widely used material, and there are lots of acronyms to describe silicone o ring types and many of the different compounds that can be used to manufacture o rings.
It is essential that you know the properties of each material in question in order to make the best and most informed decision for your application.
MQ – Methyl silicone, the simplest silicone compound offering great resistance to UV, ozone, and weathering, but comes with poor elastomeric properties. MQ silicone is often used as a base material, then processed to enhance its overall performance.
VMQ – Vinyl methyl silicone has a better compression set than MQ but no tensile strength. Here, the methyl silicone compound molecules are replaced with vinyl molecule groups to provide a wider temperature scope and better compression set. (Note: This material is not suitable for some o ring fabrication processes.)
PMQ – Phenyl methyl silicone; here, the methyl group molecules are replaced with phenyl silicone groups, making the material suitable specifically for low-temperature applications.
FVMQ – Fluorosilicone – here, fluorine is added to the molecules to make stronger bonds in order to create fewer chemical reactions and, in essence, increase the material’s resistance to chemicals.
Silicone is used in a wide selection of industries due to the benefits it can provide. Benefits such as:
- It is resistant to microbial growth.
- It can withstand and maintain its structure over a temperature range of -60 to +230 degrees Celsius.
- It offers a high degree of flexibility.
- It offers thermal stability.
- It has low toxicity.
- It is resistant to oxygen, ozone, and UV.
Difference between MQ, VMQ, PMQ, and FVMQ silicone o rings
MQ silicone o rings – for all this o ring material offers a superior resistance to ozone, UV, and weathering, this type of compound is not one of the most popular for o rings and is not commonly used on the basis that the material and o ring will need processing in order to improve its elastomeric properties and offer applications a suitable seal.
VMQ silicone o rings – providing a suitable sealing solution in a wide temperature range, making it suitable for a variety of applications, this type of silicone material also comes with an improved compression set. However, it is worth noting that VMQ silicone does have poor tensile strength.
PMQ silicone o rings – also known as PMVQ, this o ring material is specifically designed to withstand extremely low temperatures and offers a good level of resistance to varying environmental factors.
FVMQ silicone o rings – offers a good level of chemical and oil resistance; however, their hot air resistance is considered poor.
O ring suppliers UK
At Specialist Sealing Products, we offer a range of silicone seals suitable for various applications across all industries.
Providing industries with a vast selection of precision gaskets, seals, and joints, we not only sell standard sealing solutions, but we can also design and manufacture high-quality seals to meet your requirements.
From Kammprofile seals to PTFE sheeting, non-metallic and metal-clad, we have a sealing solution to suit all applications.
Providing seals and gaskets to some of the most demanding industries in the world, we work with clients in:
- Oil and gas sector
- Aerospace
- Automotive
- Chemical and petrochemical industry
- Food and drink sector
- And more.
Types of seals available from SSP
- Spiral wound gaskets
- Soft cut gaskets and various sheeting materials
- PTFE and graphite style gaskets
- Variety of soft cut gaskets and sheeting
- O rings
- Bonded seals
- Back up o rings
- Flange insulation sets
- Piping and tubing
- Pipe fittings and fasteners
- Valves and flanges
- And more.
To find out more about our expert team and to see how we can help you, visit our o ring pages online or call us to have your questions answered.
Contact us – o ring suppliers Leeds.
