When it comes to picking the right rubber for an application, you must take into consideration a number of material requirements in order to come to the correct decision on the material to use.
There are a vast range of rubbers in today’s market available to engineers, designers and buyers. So much so, that when looking through the list, it is quite easy to get lost in a maze of grades, forms, specifications, thicknesses and hardness’s.
At Silicone Engineering, we understand that with over 2000 formulations to our name, that maze can quickly start to become a headache for customers not familiar with silicone. It is our aim to work closely with you, the customer, to identify the application you intend on using our silicone products for and by using our expertise and knowledge we can then guide you to the correct material and grade.
By understanding your material requirements we can advise on certain grades and/or specifications even if silicone isn’t the right material to use, which in some environments it isn’t.
With this in mind we’ve listed a simple set of questions to think about regarding the environment and performance that the material will be exposed to, it allows us to give the best advice on material choice.
Environment – UV / Ozone / General Weathering
Will the rubber be exposed to outdoor environments where weathering could affect the rubber’s performance?
If so, you need a rubber that performs well when exposed to these conditions. Cracking, fading and brittleness can all occur if the rubber is not suited for outdoor conditions.
Silicone rubber is one of the best rubbers to use outdoors due to its excellent resistance to environmental conditions.
Will the rubber be exposed to extreme temperatures?
What temperatures (high and low) and for how long?
An environment where temperatures fluctuate will need a rubber that can cope with altering heat.
Silicone Engineering’s materials have extreme temperature resistance from -60°C to 230°C and up to 250°C intermittently.
What is the material being used for, where will it end up?
Is the silicone being used for sealing/gasketing, dampening vibration, shock absorption…?
It is important for us to gain as much detail in this question as possible in order for us as silicone experts to advise the most suitable silicone grade or indeed another rubber to use if we feel silicone is not suitable.
Will the rubber come into contact with any chemicals or fluids that could cause corrosion or damage?
If so, how long will it be in contact with the chemical for?
Knowing which chemicals affect particular rubbers is vital and at Silicone Engineering we know that silicone performs well with the majority of chemicals however there are some that silicone should not come into contact with.
Does the rubber need industry specific flame ratings such as UL-94V0, UL-HB, FAR etc
When discussing specifications and approvals it is important to know if the rubber needs to have full approval or will internal testing be suffice to prove the material can meet these ratings?
Will the material need to be free from outgassing?
This is very important when looking into hot applications as outgassing can cause fogging of lenses and damage other critical components. This is critical in applications within the Rail, Aerospace and Automotive sectors due to the safety of passengers.
Does the material need to be a specific colour or will industry standard colours be OK?
We have the capability to exact colour match if this is required?
Cost vs Material Lifespan
Why should I consider silicone when there are cheaper rubbers on the market?
Some rubbers cost a lot less than silicone, however when assessing performance and lifespan there is a clear difference. Most rubbers need replacing a lot sooner than silicone mainly due to their poorer lifespan therefore making silicone the cheaper rubber over a longer period. When comparing the cost of different rubbers make sure it is comparable in terms of performance and not just cost – silicone becomes the cheaper material over a longer period as it out lasts many other rubbers in application. cost vs lifespan!