PULLER Russian patent published in 2019 - IPC B25B27/18 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil-field equipment, in particular, to puller for extraction of hollow part with broken thread part. Puller has a bushing made with a solid cylindrical surface on the external side wall; at that, on the conical section of the tie rod there are drilled four blind holes, in each of which a separate pin is pressed with one end. At that, the bushing has four engagement elements, which are made in the form of dies for engagement with the inner wall of the extracted part, each of which is made with a conical surface enlarged towards the side of the conical section of the tie rod, with a surface on the inner wall. Each die is arranged between two adjacent said pins. Note here that outer plate wall has transverse groove accommodating unclosed ring of spring wire to press said dies against tie rod.

EFFECT: enlarging technical capabilities and simplifying the design of the device.

1 cl, 3 dwg