In order to realize the automatic measurement of wall thickness of oil casing pipe

the system referred to array of multi focusing probes rotational measurement on oil casing pipe is proposed.Based on the focusing ultrasonic probe measurement principle of wall thickness

the relationship between focusing probe’s focal length

chip size and focusing sound field are analyzed

the focusing probe which is appropriate for oil casing pipe constituted arrayed system.The optimal distance among casing connection and probe can be further researched and the relationship between arrayed probes and scan speed can be demonstrated more clearly from this arrayed system.The experimental results show that the measuring system is accurate

reliable and rapid to carry out the full-assignment towards oil casing pipe

meanwhile it also submits to API（american petroleum institute） standards which are applied in practical manufactures.