Posts Tagged ‘EVENT’

Cross Ply tyres versus Radial Ply Tyres

Cars make use of the radial tyres entirely but the ones fitted to motorbikes retain the cross-ply form of construction and even the tyre engineers state that radial tyres are not appropriate for motorbikes. This is in fact quite right as cars and motorbikes are very different and should have different tyre requirements. However, of late the radial tyres are considered to have benefits to offer to motorbikes as well.
Several piles of cord are laid on top of each other at a bias angle of 40 to 50° to make a cross ply tyre. This consequence in the creation of a cross at an direction of 80 to 100°. The layered and angled structure of ply tyres results in the tread not reacting in exact symmetry to that of the loads applied.
The symmetry is completely lacking in cross ply tyres and this can cause the tyre to run to one side nonetheless while rolling on a completely level and even surface. This effect is known as “Ply Steer”. The cross manufacture of the carcass efficiently forms parallelograms of thread imbedded in the rubber, this is not a sturdy form of construction and under driving or braking torque, upright load and centrifugal sound effects these parallelograms deform, which allows squirming of the contact area and tyre toss or diameter enlargement at elevated pace, reducing constancy and heating the tyre. Such heating eventually manifests itself as amplified rolling conflict.
By simple observation one can conclude that radial tyres create a greater and wider area of impression compared to the cross ply tyres. Such a fact highlights that radial tyres have better grip than cross ply tyres. Again in loaded conditions the radial tyres outscore the cross ply tyres as they have larger contact area with the surface of the road as they the tendency to become littile bit flat which is not the case in cross ply tyres.
Radial tyres contain less plies that is generally confined to one or two than the cross ply tyres that require three to four plies, so as to have greater flexibility in sidewalls. To maintain the entire tyre stiffness the reduction of sidewall height is required and thus results in lower profiles of 50 to 70 %. On the other hand the cross ply tyres make use of 90 to 100% of the profile. The lower profiler is an indication of having smaller diameter. The cross ply tyres have larger diameters in comparison to radial tyres of the same size. This trend contributed to the growth of 17” wheels while leading to the decline of the popular 16” wheels.
In the year 1984 radial tyres were introduced for the first time. The bias belted tyres were the most commonly used tyres until then. The cross-ply tyres were the next in line of production, which added circumferential belt plies. As and when the developments took place the older technology got replaced with newer ones giving way to improved tyre strength, agility and overall performances.

Disposal of used tyres

It is a huge challenge for the automobile industry to be in compliance with the legislations of environmental protection by safe disposal of tyres. The power rests on the Department of Environment and Resource management.

According to the Environmental Protection Regulation 2008 businesses carrying out activities such as storing of tyres or recycling of tyres that is an environmental relevant activity (ERA) have to to acquire a progress sanction and a registration certificate. The certifications are ERA 56 for storage of tyres and ERA 59 for the recycling of tyres. In addition to this the reaching of threshold limits attracts an annual fee that is calculated on the basis of aggregate environmental scores (AES) for apiece ERA.

At present the threshold limit for storing tyres is fixed at 5 tonnes or not more than 500 tyres or part of tyres. ERA 56 certification is required for exceeding this limit. The regulatory and administrative authority was formerly called as the Environmental Protection Agency and has been newly named as Department of Environment and Resource Management or DERM.

The tyre recyling units operating a facility on a commercial basis come under the ERA 59 and recyling or receiving and reprocessing of 1000 or equivalent units of tyres is the threshold limit. Hence it doesn’t attract an AES but the obtaining of DERM permit is essential. The said activity is exclusive of retreading tyres.

The Beenleigh tyre dealer was reprimanded by the Chief Executive of DERM for violating the environmental protection order and failing to remove excess stockpiles of tyres at its various properties. The Brisbane Planning and Environment Court gave the verdict stating that Section 360 of Environmental Protection Act 1994 was violated and action has to be taken against the tyre dealer. The Beenleigh Magistrates Court fined the tyre dealer a sum of $85000.

For the unlawful management of waste tyres the Environmental Protection Order was issued to the tyre dealer. The main concern of DERM was that the stockpiles of thousands of tyres were an environmental hazard, and the possibility of a fire hazard can’t be ruled out as well. Plus the area had turned into a reproduction land for insects, particularly mosquitoes. Such illegal stockpiles of tyres results in various hazards such as a risk to public health and those matters come under the Public Health Act 2005.

It is the duty of individuals to have a commitment towards their environment. Section 319 of the Environmental Protection Act 1994 highlights this issue. All the persons have moral responsibility to not carry out certain activities, which may cause harm to the environment. Until and unless the person takes all reasonable and practicable measures to minimize or prevent the harm they should not rest. The case in point revealed that the tyre dealer had failed to comply with such a duty and further he was storing tyres without a registration certificate or a development permit.
DERM was first made aware of the stockpiles of tyres from neighbors of the tyre dealer and this should serve as a cautionary tale to any of you who believe that a pile of tyres hidden behind a building are away from the public eye and scrutiny from DERM