The hot casing of LWD tool is cracked,after the hot sleeve is cracked,the axial friction used to fix its adjacent parts will be lost,which may cause the adjacent centralizers to move in axial direction and cause major safety hazards.In this paper,two typical cracking cases are analyzed from the material state,corrosion environment,interference,working condition and other external factors.Four improvement measures are proposed.The first measure is to change the heat treatment state of the material and improve the toughness of the material;the second measure is to reduce the interference and reduce the maximum stress of the hot sleeve,at the same time,the stop structure is added;the third measure is to increase the hot charging temperature and reduce the influence of heating on the material state;the fourth measure is to strictly control the dimensional accuracy to avoid uneven stress.The design calculation of the new structure's hot sleeve are carried out,and the thrust of the actual structure is verified.The improved hot casing has been operated for a long time in the well without cracking,which proves that it meets the design requirements.
NETL
NSTL
万方数据
维普
