Horseshoe to the modern hoof boot. Historians differ on the origin of the horseshoe. Because iron was a valuable commodity, and any worn out items were generally reforged and reused, it is difficult to locate clear archaeological evidence. Although some credit the Druids, there is no hard evidence to support this claim. In 1897 four bronze horseshoes with what are apparently nail holes were found in an Etruscan tomb dated around 400 B.C. The assertion by some historians that the Romans invented the "mule shoes" sometime after 100 BC is supported by a reference by Catullus who died in 54 BC.
Casing hanger the annulus and provide the means to pump out or into if necessary. The top of the casing string and annulus is usually sealed. The most common size of casing hanger is 13-3/8" with over 155,000 such units installed worldwide in 2014 alone. The contraction of the oilfield industry throughout 2015 meant that this figure was reduced somewhat to just under 120,000 units, of which 36,822 were "Pos-Grip" casing hangers. Casing hanger In petroleum production, the casing hanger is that portion of a wellhead assembly which provides support for the casing string when it is lowered into the wellbore. It