Understanding tyre pressure

How critical is correct tyre pressure?

Tyres need to be inflated to their specified pressure to avoid deformation. Deformation causes the tyre footprint and sidewall shape to change, which both have serious consequences as discussed below. Research in the USA[1] has shown that 80% of vehicles have at least one underinflated tyre.

For tar roads and high speed, above 40km/h, underinflated tyres are dangerous and also causes excess tyre wear. However, when driving slow in off-road conditions, deflating tyres in a controlled makes a big difference in  the traction.

The tyre’s footprint on the road surface, i.e. how much of the tyre is at any moment in contact with the road surface, depends on the inflation pressure. The lower the pressure, the larger the footprint. Deflating the tyres from 2.2Bar to 0.8Bar can increase the footprint with up to 100%. That means it has twice the amount of traction as when the tyres are hard. When driving  on sand or in mud, it is thus essential to deflate the tyres.

Deflating tyres also have the effect of a softer ride. With tyres deflated to 1.8Bar instead of 2.2Bar, there is significantly less rattling and shaking, which not only leads to a less bumpy and more safe ride on for instance a corrugated (sinkplaat) road, but also reduces the amount of damage to the vehicle. 

Tyres that are too soft, will wear on the  outside of the thread pattern, and tyres too hard wear in the middle.  This can half the tyre life if not corrected timely. 

Tyres run at low pressure for instance for sand driving, can only be driven at low speeds. Driving at higher speeds or longer stretches causes serious damage to the tyre side wall, since the tyre side wall has to bend and straighten with each full turn of the wheel. It is important to get the tyre pressure up again as soon as one is out of the sandy or mud terrain.

Tyre Inflation System

Although most of the above is known to many, and in addition to tyre pressure being a serious safety issue, the process of adjusting the pressure is problematic and difficult. Therefore tyre pressures are often not adjusted optimally. 

With the tyFlate system however, it becomes a walk in the park. Quick couplings and a permanently installed controlled unit and pipes make it really fast and easy to deflate or inflate the tyres. This changes the whole modus operandi and mindset around deflating and inflating of tyres. With the tyFlate, the drivers are more than likely going to adjust the pressure when necessary. The following gives and view on how the tyFlate system makes a difference to different application fields.

Application Fields

Fire and Emergency Vehicles: these vehicles often have to react to a call in a sandy or wet location. Deflation of tyres need to be fast and easy so the vehicle can drive to the emergency location without much delay. After the call, these vehicles are often far away from the closest inflation station, having to drive back at 10km/h for extensive distances if they cannot inflate the tyres again. The tyFlate deflates a large fire engine’s tyres in less than 4 minutes. And inflation depends on the vehicle’s onboard air compressor, which takes normally around 15minutes. However, inflation time, unlike deflation time, is not critical.

4×4 or offroad driving: when driving off-road, deflating tyres appropriately provide much wanted increase in traction. Sand, much and even rocky terrain require tyre pressure to be reduced to a low as 0.3Bar. After conquering the terrain, tyres need to be inflated again. 

Border control: these vehicles often patrol remote borders and on sand and dirt roads. Having a puncture so far out is but one issue. The road condition can vary from tar to thick sand.

Commercial Trucking: similarly, when not inflated properly, the tyre life is reduced dramatically. Hard tyres with a low load, i.e. too high inflation, also causes excessive hammering on the vehicle as a whole, that again lead to unnecessary wear on the chassis, drive train and all hang on components. Another issue is when one tyre is not inflated enough, it causes more loading on the tyre next to it, again, reducing tyre life and  even being a safety issue. Trucks typically have 22 or more tyres, making the usual inflation process long and tedious.  With the tyFlate system, the process of checking and correcting the tyre pressure is easy and fast and can be run unattended while the driver is doing other duties, filling up, loading, resting, etc. 

Agriculture vehicles have the additional issue of leaving deep footprints in the soil, where valuable produce need to grow. Various tests by Michelin, Good Year and others have shown that when using low tyre pressure, these vehicles leave only shallow ruts and the produce continue to grow where the vehicle tyres rolled over, which is not the case when the tyre pressure is high. Reduced tyre pressure also improve fuel consumption and reduce stress on the entire drivetrain. Farmers however suffer most damage from flat tyres. Vehicles are driven with under-inflated tyres and often tyres as permanently damaged. With an easy to use system, tyres can quickly and easily be inflated when needed.

Other vehicles and industries can also benefit from an easy and fast way of inflating and deflating tyres. These include game drive vehicles, security, road side assistance, police.

Application Fields
  • Agriculture
  • Emergeny Vehicles
  • Field support vehicles
  • 4x4 Enthusiast
  • Off-road trailers
  • Safari vehicles
  • Game drive vehicles
  • Off-road vehicles
  • Recovery vehicles
  • Off-road caravans
Research Articles

1.A Literature Overview of Central Tyre Inflation Systems, T Plett; http://efwe.ukzn.ac.za/libraries/researchseminars/pletts_t.sflb.ashx

2. Influence of Tyre Inflation Pressure on Fuel Consumption, Vehicle Handling and Ride Quality. A Varghese; http://publications.lib.chalmers.se/records/fulltext/193515/193515.pdf

3. Underinflated Tyre - Case Study & Resarch;‎ https://accidentspecialist.co.za/wp-content/uploads/2016/12/Underinflated-tyre-case-study-research.pdf

The correct tyre pressure setting for any type of surface - it can save your life