METHOD OF OILWELL TUBING PIPE-END UPSETTING Russian patent published in 2011 - IPC B21J13/02 B21J5/08 

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming and can be used for producing oilwell tubing. Pipe-end upsetting is carried out by forming outer surface of upset part and zone arranged behind upset part, as well as inner surface of upset pipe-end. Forming of upset part outer surface and zone arranged there behind, is performed using upsetting die. Said die has cylindrical and taper sections to form upset part and taper section to form zone behind upset part. Upset pipe-end inner surface is formed by upsetting punch with section for aforesaid forming. OD of said section exceeds by 0.6-1.5 mm the rated ID of oilwell tubing smooth part. Note here that upsetting die and punch are used with due allowance for thermal expansion factor of upset metal making 1.0065 -1.0085.

EFFECT: upset pip-ends that do not require additional machining.

2 dwg