how a tennis ball gets approval
TRANSCRIPT
How A Tennis Ball Gets Approval?
The balls and rackets are the most important part of tennis.
In order to be approved for tournaments, a ball must meet ITF regulations
The tennis ball should posses the following qualities like :- :-consistent playing properties
:- sufficiently durable and :- Withstand repeated high-speed impacts with the racket and
surface.
Which ball types are available for surfaces?
:- Type 1 ball :- It's slightly harder, fast-speed ball which is intended to use on slower court surfaces.
Type 2 ball :- This ball type can be used in any
location and court type.
Type 3 ball :- It's bit larger and slow-speed ball used in faster court surfaces.
How the ball gets approval from ITF?
A strict testing procedure is taken place to determine whether the balls are meeting the ITF specifications or not?
The different steps for ball testing are :- - Acclimatisation
- Pre-compression (and conditioning) - Mass - Size
- Deformation - Rebound - Durability
Acclimatisation
The balls need to be acclimatised for 24hrs before testing in climate controlled laboratory.
As per studies, a tennis ball is also affected by temperature and humidity.
Note:- High humidity can increase the mass of the ball by increasing the moisture content of the felt, and high
temperature can increase the bounce height.
Pre-Compression
Before any testing, balls are sent to the pre-compression machine where it compresses each ball 2.54 cm (1 inch)
three times from three directions using pneumatic actuators to remove any “set” in the ball.
Previously the acceptable mass for balls was between 54.66 and 59.04 grams.
Mass
Then it was changed to 56.7-58.5 grams in the year 2000.
Size
This test will determine whether a ball is in the appropriate size or not.
Each ball needs to pass the test through the two rings of go or no-go manner.
Deformation
The ball deformation test explains the behavior of tennis balls after impacted with the racket and court surface under a particular load
or pressure.
The deformation test is divided into 2 parts :-
:- return deformation
:- forward deformation
Rebound
The rule about “how the ball should bounce in surface” was set in 1925. This test measures the height of rebound when
it's released vertically.
The rebound should (for all Type 2 balls) be 135-147 cm (53-58 inches).
The range for balls at high altitude is 122-
135 cm (48-53 inches).
Durability :-
The durability test is introduced in the year 2009 by ITF to understand the ball longevity in different surfaces.
