Impossible d'afficher cette page de l'infobrol
Type d'erreur (18-01)
Undefined constant "be\gaudry\photo\DAY_IN_SECONDS"Veuillez réessayer dans quelques minutes…
Steph
A headframe(also known as a gallows frame, winding tower, hoist frame, pit frame, shafthead frame, or headgear) is the structural frame above an underground mine shaft. Modern headframes are built out of steel, concrete or a combination of both. Timber headframes are no longer used in industrialized countries, but are still used in developing nations. Traditionally steel headframes are used when a drum hoist is employed, and concrete headframes are built for friction hoists, however a steel headframe can be used with a friction hoist for shafts with a smaller capacity and depth.From Wikipedia, the free encyclopedia (version june 7, 2012).