In the early days, screws were made from wood or bone and were primarily used for binding and fastening objects together. They were laboriously crafted by hand, with each screw requiring hours of meticulous work to shape and sharpen. Despite their limitations, these early screws played a crucial role in the development of early civilizations, allowing builders to construct more sturdy and reliable structures.
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The rubber lip, in contact with the shaft, forms a tight seal that can withstand varying temperatures, pressures, and speeds The rubber lip, in contact with the shaft, forms a tight seal that can withstand varying temperatures, pressures, and speeds
Nitrile rubber is widely used due to its good chemical resistance, oil resistance, and moderate temperature range Nitrile rubber is widely used due to its good chemical resistance, oil resistance, and moderate temperature range