DEVICE FOR AUTOMATIC CHECKING OF DRILLING PIPE THREADED JOINTS FOR WEAR Russian patent published in 1999 - IPC

FIELD: drilling equipment. SUBSTANCE: device is used for automatic checking for wear of threaded joints of drilling pipes on drilling rigs primarily in oil and gas production industry. Device has master coupling and nipple, generator of acoustic oscillations installed for generating oscillations in body of drilling rod, acoustic sensors for receiving acoustic oscillations fastened on master coupling and nipple which is located for connection respectively with nipple and coupling under check. Interconnected by means of communication lines are units for forming master threshold signal and logic units for comparing signals from acoustic sensors and preset threshold signal. In addition, device is provided with band-pass filters installed in communication line directly after each of acoustic sensors. Threshold signal forming unit has means for adjusting level of threshold signal. Included in communication line after band-pass filter is multiplier with one of its inputs connected with output of band-pass filter. Device can be provided with additional acoustic sensor with its input acoustically linked with generator of acoustic oscillations, and its output is connected through band-pass filter and retarding unit with second input of multiplier. Application of aforesaid embodiment of device enhances reliability of bore-hole drilling process due to less probable emergency occurrences caused by poor condition of threaded joints of drilling string. EFFECT: higher efficiency. 5 cl, 2 dwg