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Old 02-27-2019, 05:38 PM   #211
Tireman9
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Join Date: Sep 2018
Location: Akron
Posts: 453
Quote:
Originally Posted by CWtheMan View Post
If the tire testing procedures for Passenger tires differs from the procedures used for testing Light Truck tires but is acceptable because they have different features to perform, than why question the testing procedures for Special Trailer tires? The are just followers.

If the end result of a test is a pass, than what's the beef?

The "beef" is that the load formula used by US Tire & Rim Association is based on a stated 65 mph operating speed. For someone so enamored with published regulations I don't understand the confusion.
The reason ST tires carry 10 to 20% more load than LT tires of the same dimension at the same inflation is simply because of the stated speed restriction. Otherwise, there is no rational reason for two otherwise identical tires to have different load capacities.


If the difference was based on the tire construction then I would expect to see diferent loads for Polyester tires vs Steel body tires, but those differences simply do not exist.



Anyone can read and blindly follow a regulation but it takes an actual working knowledge of the product to understand the reasoning behind the regulation, to understand the new Science i.e. "Interply Shear" and the tools needed to evaluate the effects (Finite Element Analysis) and point out the problems with simply blindly following the decades old regs.
I bet that today's modern aircraft would not be allowed and maybe not even able to fly if they had to operate under 50-year-old "regulations".



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