Hydrostatic Test and Valve Service
Visual Inspection and Valve Service
As we are unable to send cylinders through the post we operate a collections and delivery service in the Obsequio van.
The areas that we cover are shown on the map. Please contact us to arrange collection.
We are an IDEST accredited centre for the testing of cylinders.
Cylinder testing is (by a long way) the most important testing to get done on your equipment. When cylinders fail, they can cause devastating results. In fact if a 10 litre, 200 bar bottle fails it is fatal to anyone standing within a 7 metres radius on wave pressure alone (not even accounting for the metal shrapnel)!
Due to the danger that cylinders can pose, all reputable filling stations will only charge your cylinders if they have been tested.
We carry out a full hydrostatic test every 5 years, with visual inspections every 2.5 years for diving cylinders. We also service the valve and make sure that it is safe for you to use.
What is hydrostatic testing?
There are two main ways that you can carry out a hydrostatic test; however the simplest way is by filling your cylinder with water and pressurising it up. If the water stays in your cylinder at test pressure it is deemed to be safe for you to use (this is known as proof testing).
If it doesn't, then we know that it wouldn't be safe for you to use.
Hang on! I spend my entire life trying to keep water out of my cylinder!
Don't worry we dry them very carefully afterwards! The reason that we use water is due to stored energy. Gas is compressed very easily, and as a result at high pressures has lots of stored energy. By using water instead (which can only be compressed by a very small amount) we dramatically reduce the amount of energy contained in the cylinder. That way if it does fail, we would get a cylinder split rather than explode.
How is a visual inspection different from a hydrostatic test?
With diving cylinders we carry out a visual inspection every 2.5 years. This is mainly to check that they haven't been exposed to any seawater which would cause them to rust. The photo above is from a customer's cylinder. It looked immaculate on the outside, but on the inside...
During a visual inspection we don't fill your cylinder with water. It's just a quick check to make sure everything is okay inside.
The photo on the right is the water that we got out of another cylinder. Luckily the customer had realised something was wrong and didn't dive with it!
I dive with oxygen rich gas, why do I need to get my cylinder O2 cleaned?
We O2 clean cylinders in order to prevent the build up of hydrocarbons inside your tank.
At high pressures the oxygen can combine with the hydrocarbons and combust. Trust us, this is nasty when it is on your back!
When we O2 clean your cylinders, we use a chemical which reacts with the hydrocarbons and strips them out of your cylinder. Unfortunately over the course of a cylinder's lifetime new hydrocarbons can be added to the cylinder. This is usually in the form of oil from compressors (which is one of the reasons we test for oil during our air purity tests). You should get your cylinder O2 cleaned every 15 months to make sure it is safe.