Standards Advisory

 

 

GUIDELINES ON THE APPLICATIONS AND USE OF TYRES

 

It is very important for vehicle owners to select suitable tyres for their intended purposes in order to obtain maximum use and to ensure safety.

 

Some of the factors to be considered in order to prevent tyre failure are as follows:

  • Inflation Pressure – Special attention must be given to the inflation pressure rating of your tyres, since the incorrect pressure can lead to tyre failure. In the case where a tyre is over-inflated, damage to the strut can result. Under inflation can lead to increase deflection and flexing, which can result in carcass deterioration of the tyre.
     

  • Load – A tyre is designed to carry a given load which must not be exceeded.  If a tyre is over loaded by putting more load upon the tyre than it is designed to carry, this would adversely affect the flex area and the rate of wear of the tyre, and as a result could reduce the life of the tyre.  Never over load your vehicle beyond the carrying capacity.
     

  • Speed – When tyres are in use, they flex load producing internal stress which is converted to heat.  The amount of heat increases as the flexing increases due to the load, inflation pressure and speeding.  As such if the tyre is sustained at high speed in excess of the maximum speed rating on the tyre for any length of time, the tyre will be in dangerous condition and could blowout.  Do not exceed the speed rating stated on the tyre at any given time.
     

  • Tyre width – The width of the tyre must correspond with the width of the rim it is mounted on, in order to ensure proper usage and safety.  Narrow tyres mounted on broad rims often tend to wear on the side walls causing tyre failure.  Always check to ensure that the width of the tyre purchased, corresponds with the width of the rim it is to be mounted on.
     

  • Temperature Grades – The temperature grades (A, B and C) represent the tyre’s resistance to the generation of heat and its ability to dissipate heat.  Temperature grade is established for a tyre that is properly inflated and not overloaded.  However, inspite of the temperature grades, excessive speed, under inflation, or excessive loading, can cause heat build up and possible tyre failure.  Remember to always pay close attention to these parameters.

 

Users are reminded that proper consideration and attention must be given to these factors when attending to the application and use of tyres to ensure their own safety and the safety of loved ones.

 

 

 

HOW TO READ A TYRE SIDEWALL

 

 

 

 

  1. Maximum inflation pressure
  2. Type of tyre e.g. passenger
  3. Width of the tyre in millimeters
  4. Ratio of height to width (Aspect ratio)
  5. Types of construction of the tyre e.g. Radial
  6. Diameter of the wheel (Rim) in inches
  7. Load index e.g. 640 kg
  8. Speed symbol e.g. 70 km/h
  9. US D.O.T Safety Standard Code
  10. Manufacturer of the tyre e.g. Good Year.
  11. Tyre Ply composition and materials used e.g. 2 Plies Nylon
  12. Tread wear, traction and temperature grades
  13. Tube type or tubeless

 

It is very important for both sales personnel and consumers to learn exactly what all the tyre sidewall codes mean so as to minimize the number of complaints relating to the selection and use of tyres.

 

 

For more information contact

GUYANA NATIONAL BUREAU OF STANDARDS

FLAT 15, Exhibition Complex, Sophia, Georgetown

Telephone Nos. 225-6226, 227-7890, 227-7072

Email:gnbs@neworksgy.com