What is The Psi of Your Tyres(2)


I know i have severally discussed the major causes of tyre blowouts which apparently most people are not aware and they include incorrect tyre inflation, especially under-inflation. Under-inflation causes two things that lead to tyre blowouts; it causes undue flexing of the tyres as the vehicles speeds along the undulating surface of the road. This causes a separation between the internal materials used in making the tyre and the rubber flesh that holds the materials. This separation weakens the tyre.it also causes an increase in what is known as rolling resistance (rr) as the vehicle moves. The increased rr generates a tremendous amount of heat. This heat, together with the separation of the internal materials of the tyre as stated above, leads to an explosion or blowout.

Incorrect tyre inflation could also cause accidents in other ways. When a tyre is incorrectly inflated (over inflation or under-inflation), it makes a partial contact with the road surface and so does not have a firm grip on the surface. With over-inflation, the edges of the contact patch (the part of the tyre that should be in contact with the road surface) do not touch the ground. While with under-inflation, the crown (the middle portion of the tyre) of the contact patch does not touch the ground. So either way, you have an impartial contact of the tyre on the road surface and so less grip.

This impartial contact could cause accidents in various ways: since the tyres don’t have a firm grip on the road surface, it prolongs the stopping distance when the brakes are applied in an emergency and this could make the vehicle crash into the object it wants to avoid.  It could also lead to loss of control of the vehicle when speeding. This is more with over-inflated tyres.high vehicles like trailers, tankers, etc could lose their balance when they hit a bump, pot hole, or whi;e descending a sharp bend. The situation can be likened to someone with one leg shorter than the other- over-inflation representing the longer leg while under-inflation, the shorter leg. When given a push, such a person can easily loose balance. No wonder these vehicles fall and loose brakes easily when subjected to abnormal road conditions like bumps, potholes and bends.

A study conducted by my friend Ucheagwu Sab a couple of years ago revealed shocking discovery- at orile tanker park. Our observation at the tanker park, orile shows that most of these vehicles have a combination of over-inflated and under-inflated tyres. To our greatest surprise, most of those with under-inflation were deliberate. According the drivers, those tyres were weak and if properly inflated, they could burst. This is another dangerous ignorance at work. Using weak tyres is enough bad news. Under-inflating them makes matters worse. Under-inflation, as explained above, will actually accelerate their likelihood of bursting. In fact, if you trace the causes of most accidents, you may discover that incorrect tyre inflation is directly or indirectly implicated.

  It is important to note that a tyre that is correctly inflated will handle bad roads, speed and other road conditions far better than one that is not correctly inflated. These will result in drastic reduction in road accidents. Correct tyre pressure is such a vital issue in reduction of road accident that america, as well as some other developed countries, made it law that all vehicles manufactured from 2008 must be equipped with automatic tyre pressure monitoring system (atpms). This device monitors tyre pressure situation every second and alerts the driver through a monitor on the dashboard about any tyre that has incorrect pressure in it so that the driver will take action before it is too late.

 Like I told you last week,analysis of tyres with wrong inflation (PSI) showed that 50% private vehicles tyres are both under and over inflated. The analysis also indicated that 51% of commercial vehicles with wrong inflation are under inflated while 49% are over inflated.

While Government vehicles tyres checked had 39% under inflated, while 61% were over inflated.These findings reminds me of confessions made by some vulcanisers last year during the nationwide campaign.The first came from 66years old, sunday nze,(not real names)who is a father of three and a devout christian  and is so  passionate  about his profession as a vulcanizer that one would almost mistake him for a top executive in one of the oil companies. Passion, dedication and fear of God has been the cornerstone of my profession since 1981 and i have no regrets doing what provides bread and butter for my family, he says humbly.

 The man who is an  executive of the association in port Harcourt, the Rivers state capital, caught my attention  during the stakeholders platform put together by the Federal Road Safety Corps in keeping with the ongoing nationwide free vehicle tyre check meant to raise awareness on tyre knowledge and reduce tyre related road traffic crashes.incidentally,the  programe was my maiden function  as i resumed in port Harcourt  as zonal commanding officer in charge of Rivers, Cross Rivers,Bayelsa and Akwa Ibom states.Mr Nze, whose spoken english was as fluent as one in a different vocation, stunned me  with his confession  during the campaign in Port Harcourt where, he told the audience how motorist have overnight become emergency vulcanizers who ignore manufacturers guide for tyre inflation which was discussed here last week to dictate what they presume to be the appropriate inflation for their tyres.some, he confessed insist on inflating the tyre up to between above70.greedy vulcanizers he however noted, would in the name of doing business oblige, not   minding  the risk or even bother to educate motorists on the dangers of over or under inflation.

He concluded solemnly by saying as one who fear God, ‘I would rather insist on the right guage or tell you to kindly go to another vulcanizer because i know that should that customer die through a tyre induce road traffic crash, the God i serve will hold me responsible’’ .For me this is the crux of the matter-truth and fear of God in whatever we do even though other vulcanizers bluntly said they would gladly do the bidding of the customers and pocket the cash