| 摘要 |
An electrically insulative gap sub for inclusion in a drill string that consists of upper and lower threaded joint members, an inner sleeve connected to extend axially from the upper joint member, an outer sleeve connected to the lower joint member and extending in concentric spacing over the inner sleeve, and a plurality of differently configured, annular blocks of insulative gap material serially arrayed and filling the void in between inner and outer sleeves. The gap material is a high performance molded resin capable of transmitting the requisite torque, tensile and compressive forces encountered along the drill string.
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