This invention relates to a corrosion prevention and thermal insulation apparatus for oil extraction plant, especially used on wellhead control valve and its pipe joining assembled type corrosion prevention and thermal insulation "jacket" of oil well, water well and gas well. It adoptes high effect insulating material according to the structure shape of control valve and pipe joining of various wellhead, with profile modelling die preforming model case. On the inner surface of model case, the strength treatment and corrosion prevention treatment is carry on, then the model case is assembled on the control valve and its pipe joining to split assemble an integral body. The said device not only raises heat preservation character, saves man-hour, saves material, reduces labour strength, drops crude oil ton cost, but also its outward appearance is neat, the standardization and normalization are realized easily and raises the civilized management level of well. |