Detalis about Cricket Ball
>> Friday, January 15, 2010
A cricket ball is a hard, solid ball used to play cricket. Constructed of cork and leather, a cricket ball is heavily regulated by cricket law at first class level. The manipulation of a cricket ball, through employment of its various physical properties, is the staple component of bowling and dismissing batsmen – movement in the air, and off the ground, is influenced by the condition of the ball and the efforts of the bowler, while working on the cricket ball to obtain an optimum condition is a key role of the fielding side. The cricket ball is the principal manner through which the batsman scores runs, by manipulating the ball into a position where it would be safe to take a run, or by directing the ball through the boundary.
In Test cricket and most domestic games that spread over a multitude of days, the cricket ball is traditionally coloured red. In many one day cricket matches, the ball is coloured white. Training balls of white, red and pink are also common, and wind balls and tennis balls in a cricket motif can be used for training or unofficial cricket matches. During cricket matches, the quality of the ball changes to a point where it is no longer usable, and during this decline its properties alter and thus influence the match. Altering the state of the cricket ball outside the permitted manners designated in the rules of cricket is prohibited during a match, and 'ball tampering' has resulted in numerous controversies.
Cricket balls, which weigh on average between 155.9 and 163.0 grams, are known for their hardness and for the risk of injury involved when using them. The danger of cricket balls was a key motivator for the introduction of protective equipment. Injuries are often recorded in cricket matches due to the ball, and a small number of fatalities have been recorded or attributed to cricket balls.
Manufacture
Cricket balls are made from a core of cork, which is layered with tightly wound string, and covered by a leather case with a slightly raised sewn seam. In a top-quality ball suitable for the highest levels of competition, the covering is constructed of four pieces of leather shaped similar to the peel of a quartered orange, but one hemisphere is rotated by 90 degrees with respect to the other. The "equator" of the ball is stitched with string to form the ball's prominent seam, with a total of six rows of stitches. The remaining two joins between the leather pieces are stitched internally. Lower-quality balls with a 2-piece covering are also popular for practice and lower-level competition due to their lower purchase cost.
For men's cricket, the ball must weigh between 5.5 and 5.75 ounces (155.9 and 163.0 g) and measure between 8 13/16 and 9 in (224 and 229 mm) in circumference. Balls used in women's and youth matches are slightly smaller.
Cricket balls are traditionally dyed red, and red balls are used in Test cricket and First-class cricket. White balls were introduced when one-day matches began being played at night under floodlights, as they are more visible at night. Professional one-day matches are now played with white balls, even when they are not played at night. Other colours have occasionally been experimented with, such as yellow and orange for improved night visibility, but the colouring process has so far rendered such balls unsuitable for professional play because they wear differently to standard balls. A pink ball was used for the first time in an international match in July 2009 when the England Women's team defeated Australia at Wormsley [3]. The white ball has been found to swing a lot more during the first half of the innings than the red ball and also deteriorates more quickly, although manufacturers claim that white and red balls are manufactured using the same methods and materials.[1]
Cricket balls are expensive. As of 2007, the ball used in first class cricket in England has a recommended retail price of 70 pounds sterling.[2] In test match cricket this ball is used for a minimum of 80 overs (theoretically five hours and twenty minutes of play). In professional one day cricket, at least two new balls are used for each match. Amateur cricketers often have to use old balls, or cheap substitutes, in which case the changes in the condition of the ball may not be experienced in the same manner as that which occurs during an innings of professional cricket.
Condition of a cricket ball
A new, highly polished ball is used at the start of each innings in a match. A cricket ball may not be replaced except under specific conditions described in the Laws of Cricket:
- If the ball becomes damaged or lost.
- If the condition of the ball is illegally modified by a player.
- In Test cricket, after 80 overs, the captain of the bowling side has the option to take a new ball.
- In One Day Internationals, there is a mandatory change of the ball at the start of the 35th over of each innings. The replacement will be a clean used ball, not a new ball. This rule was introduced in June 2007[4]
The ball is not replaced if it is hit into the crowd - the crowd must return it. If the ball is damaged, lost, or illegally modified, it will be replaced by a used ball in similar condition to the replaced ball. A new ball can only be used after the specified minimum number of overs have been bowled with the old one.
Because a single ball is used for an extended period of play, its surface wears down and becomes rough. The bowlers will polish it whenever they can - usually by rubbing it on their trousers, producing the characteristic red stain that can often be seen there. However, they will usually only polish one side of the ball, in order to create 'swing' as it travels through the air. They may apply natural substances (i.e. saliva or sweat) to the ball as they polish it.
The seam of a cricket ball can also be used to produce different trajectories through the air, with the technique known as swing bowling, or to produce sideways movement as it bounces off the pitch, with the technique known as seam bowling.
Since the condition of the cricket ball is crucial to the amount of movement through the air a bowler can produce, the laws governing what players may and may not do to the ball are specific and rigorously enforced. The umpires will inspect the ball frequently during a match. It is illegal for a player to:
- rub any substance apart from saliva or sweat onto the ball
- rub the ball on the ground
- scuff the ball with any rough object, including the fingernails
- pick at or lift the seam of the ball.
Despite these rules, it can be tempting for players to gain an advantage by breaking them. There have been a handful of incidents of so-called ball tampering at the highest levels of cricket, involving players such as Pakistani fast bowler Waqar Younis and former England captain Mike Atherton.
A new cricket ball is harder than a worn one, and is preferred by fast bowlers because of the speed and bounce of the ball as it bounces off the pitch. Older balls tend to spin more as the roughness grips the pitch more when the ball bounces, so spin bowlers prefer to use a worn ball. Uneven wear on older balls may also make reverse swing possible. A captain may delay the request for a new ball if he prefers to have his spin bowlers operating, but usually asks for the new ball soon after it becomes available.
Dangers of cricket balls
Cricket balls are notoriously hard and potentially lethal, hence today's batsmen and close fielders often wear protective headgear. Raman Lamba was killed when hit on the head while fielding at forward short leg in a club match in Bangladesh. Only two other cricketers are known to have died as a result of on-field injuries in a first-class fixture. Both were hit while batting: George Summers of Nottinghamshire on the head at Lord's in 1870; and Abdul Aziz, the Karachi wicket-keeper, over the heart in the 1958-59 Quaid-e-Azam final. Ian Folley of Lancashire, playing for Whitehaven in 1993, died after being hit.
Frederick, Prince of Wales is often said to have died of complications after being hit by a cricket ball, although in reality this is not true - although he was hit in the head by one, the real cause of his death was a burst abscess in a lung. Glamorgan player Roger Davis was almost killed by a ball in 1971 when he was hit on the head while fielding.
Numerous injuries are reported to health institutions, worldwide, in relation to cricket ball injuries including: occular (with some players having even lost eyes), cranial (head), digital (fingers and toes) and testicular.
Cricket ball swing
The key to making a cricket ball swing is to cause a pressure difference between the two sides of the ball. The air pressure depends on the flow of air over each side of the ball. Swing is generated when bowlers, by accident or design, disrupt the flow of air over one side of the ball.Normal swing is achieved by keeping one side of the ball polished smooth and shiny, and delivering the ball with the polished side forward, and the seam angled in the direction of desired swing. The outswinging delivery moves away from the right-handed batsman, while the inswinger moves in towards him. Normal swing is achieved by maintaining laminar boundary layer air-flow on the shiny side whilst creating turbulent flow on the seam side. These deliveries, particularly the outswinger, are the bread and butter of opening bowlers who get to use the ball while it is still new. Reverse swing is very different from conventional swing. Although the seam is oriented in the same way as for an outswinger and the action is the same, the rough side of the ball is to the fore, and the ball moves in to the batsman like an inswinger. Reverse swing is achieved when the ball is bowled very fast. In this case the air flow will become turbulent on both sides before it reaches the seam.
Alternatives to cricket balls
Sometimes alternatives to a real cricket ball may be preferred for reasons of safety, practice, availability and cost. Examples include a tennis ball (most favoured) or a plastic version of the cricket ball, known as an Incrediball.
Many casual players use a tennis ball wrapped in layers of some type of adhesive tape (often electrical tape), which makes the relatively soft tennis ball harder and smoother. This is commonly referred to as a tape ball. A common variant is to tape only half the tennis ball, to provide two different sides and make it easy to bowl with prodigious amounts of swing.
DIFFERENT TYPES OF CRICKET BALLS
 | KING WHITE: White, leather mens size cricket ball. Made in India, conforms to MCC specifications, 5 1/2 oz (156g). Hand stitched with a black seam and water proofed with a glossy varnish for extended life |
| | MATCH RED: Red Incrediball. Plastic exterior with poly core, safer than ordinary cricket balls but with a seam and similar bounce. Available in adult and junior sizes |
| | SUPER CAVALIER Top quality alum tanned leather, 4 pieces, hand stitched. Ideal for English conditions. As used in the ICC Trophy 2000 at Sharjah. Special Grade A - 5 1/2oz | |
| | Reader brand Junior size 4 3/4oz cricket ball, made in India. Ideal for school and junior club cricket at Under 13 years old age group and below |
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