In the never ending battle to protect pipework and extend its lifespan, one method proves particularly popular for a variety of reasons – the rubber lined pipe.
Rubber is a tried and test solution which has been used in industry since the 1920s. Professionals deploying it for nearly 100 years tells you everything about how effective it is, standing the test of time whilst new repair and protection compounds have come and gone.
But why is rubber so effective and so enduring? We are going to look at the purposes and the benefits of rubber lined pipe.
What is rubber lined pipe?
A pipe which is rubber lined has rubber sheets, extruded tubes or a high-build rubber repair compound applied to its internal surface.
Lining can take place during the fabrication of a pipeline or when it has been installed. Pre-existing pipes which are to be lined have to be inspected for defects which could interfere with the process.
Rubber lining is most commonly applied to steel pipes in industrial settings, providing a barrier between the metalwork and whatever fluid the pipework is carrying.
Types of rubber used to line pipes
A variety of rubber types are used to line pipes with material selection determined by pressure, temperature and the contents of the pipework.
Natural rubbers are suitable for the majority of applications. They are resistant to hydrochloric acid and sulphuric solutions, esters, most alcohols and most chemicals other than strong oxidising agents.
Rubber is graded as either soft or hard. The harder the rubber, the less flexible it tends to be. Soft rubber is therefore more suitable for absorbing impact, as well as being easier to apply to existing pipework.
Synthetic rubber linings are much more specialised. There are numerous synthetics manufactured for specialised pipe lining application.
Chloprene rubber lining for example has good weathering and ozone cracking resistance. This makes it better suited for desalination plants and in seawater cooling systems.
Butyl and chlorobutyl linings are unaffected by cold weather or rapid temperature changes, whilst EPDM has high tensile strength and excellent resistance to puncture and microbial attack.
The benefits of rubber lining
The reason for rubber lining pipes is to make them more durable. This is applicable to pipes across different industries and transporting different substances.
Where a pipe is carrying aggressive chemicals, rubber protects the frame from attack. Similarly, rubber acts as a shield against internal corrosion, helping prevent the weakening of the structure which can ultimately lead to leaks or bursts.
Highly abrasive materials passing through steel pipes will soon weaken the line as they crash into or rub against it, leading to leaks and bursts.
Rubber lining prevents this by absorbing the damage and preventing the pipe interior becoming attacked. For this reason, rubber lined pipes are considered essential in the mining industry.
Finally, the elastic properties of rubber and its strength allow it to withstand vibration, temperature and pressure. Rubber lining is therefore seen as a means of preventing potential ignition or explosion.