Wire rod wire rod holder name suggests is. Appeared in various rural - Field - street - street, it is one of the early Chinese critical infrastructure. Early various poles are from wood started, even including voltage level is not too high-voltage poles. Later, due to the development of steel and reinforced concrete, and technical requirements, instead of the two materials most woods, but also for the progressive scarcity of wood, the city which is basically difficult to see the wood. However, in some less developed areas to set up telephone lines also use wood, because wood is lightweight, easy to set up, and a small telephone line load and tension, wood can be competent, telephone lines are subject to change shift lever is also convenient . So, now there are some wooden telephone pole. development path Early various poles are from wood started, even including voltage level is not too high-voltage poles. Later, due to the development of steel and concrete, combined with the technical inquiry, using the principle of centrifugal force, manufacturing, reinforced concrete cone cement pole, most of the other tracks instead of wood cement poles, cement poles durable, corrosion resistance, temperature difference high strength, crack. But also for the gradual scarcity of timber, cement poles look smooth and beautiful, easier to beautify the city, the city which is basically difficult to see the wood. However, in some less developed areas to set up telephone lines also use wood, because wood is lightweight, easy to set up, and a small telephone line load and tension, wood can be competent, telephone lines are subject to change shift lever is also convenient . So, there are some wooden telephone pole.