Lightening holes

Lightening holes are holes in structural components of machines and buildings used by a variety of engineering disciplines to make structures lighter. The edges of the hole may be flanged to increase the rigidity and strength of the component. The holes can be circular, ovals, or rectangles with rounded edges, but they should never have sharp corners, to avoid the risk of stress risers, and they must not be too close to the edge of a structural component.

Motor racing

Lightening holes became a prominent feature of motor racing in the 1920s and 1930s. Chassis members, suspension components, engine housings and even connecting rods were drilled with a range of holes, of sizes almost as large as the component.

This drive towards lightening was based on a misunderstanding of the component's mechanical behaviour. The assumption for a H girder was that all of the resistance to bending stresses was carried in the two top and bottom flanges of the girder, with the central web only carrying out a spacing function. The central web could thus be drilled indiscriminately, supposedly without weakening the overall girder. This was based on two fallacies: firstly that the only forces on the beam were simple bending forces in the plane of the web. In practice, a more complicated force, such as an unexpected torsional twisting from a sudden suspension bump overloaded the now-weakened central web and the lightened beam failed immediately. Secondly, the assumption that the ideal forces were separated into the top and bottom flanges was increasingly unrealistic with the development of stressed skin and monocoque designs, where loads were more evenly shared. In these designs there was no "unloaded web" that could be safely drilled.

Hole

A hole is an opening.

Hole or holes may also refer to:

Science

Technology

Construction

Entertainment

Holes (Pint Shot Riot song)

"Holes" was the third single by Coventry-based indie rock band Pint Shot Riot. The single was the band's first to be released on 7" vinyl. The track later features on the band's debut EP Round One in 2009.

The track charted in the top 10 of the UK indie charts.

The track was featured on Soccer AM on 'Holes' to Goals Montage 4 October 2008

Track listing

References

External links

Holes (novel)

Holes is a 1998 young adult mystery comedy novel written by Louis Sachar and first published by Farrar, Straus and Giroux. It won the 1998 U.S. National Book Award for Young People's Literature and the 1999 Newbery Medal for the year's "most distinguished contribution to American literature for children". In 2012 it was ranked number 6 among all-time children's novels in a survey published by School Library Journal.

Holes was adapted as a feature film of the same name by Walt Disney Pictures, released in 2003.

Plot

Present day

Stanley Yelnats IV is an overweight 14-year-old boy from a family of destitutes that is affected by "a hex," which they blame on at Stanley's "no-good-dirty-rotten pig-stealing-great-great-grandfather". Stanley's latest adversity is to be wrongly accused of stealing a pair of shoes contributed to a children's orphanage by the baseball player Clyde "Sweet Feet" Livingston.

As retribution, Stanley is sent to Camp Green Lake, a juvenile imprisonment and disciplinary facility which, unlike its name suggests, is in the middle of a sterile desert.