Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Gardner Denver Inc
Original Assignee
Gardner Denver Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Gardner Denver IncfiledCriticalGardner Denver Inc
Priority to ES299745ApriorityCriticalpatent/ES299745A1/en
Publication of ES299745A1publicationCriticalpatent/ES299745A1/en
A percussion drill rod comprising an elongated metal shaft of varying cross section, having a widened cross section, a tree comprising longitudinally defined segments of different hardness and strength, including a segment of minimum hardness and strength, arranged this last segment entirely within said greater thick portion, whereby the unit load created in this last segment in response to the stress exerted on the tree is minimal. (Machine-translation by Google Translate, not legally binding)
ES299745A1964-05-121964-05-12A percussion drill bar (Machine-translation by Google Translate, not legally binding)
ExpiredES299745A1
(en)