Keszthelyi v. Doheny Stone Drill Co.

47 F.2d 648, 1931 U.S. Dist. LEXIS 1177
CourtDistrict Court, S.D. California
DecidedFebruary 23, 1931
StatusPublished

This text of 47 F.2d 648 (Keszthelyi v. Doheny Stone Drill Co.) is published on Counsel Stack Legal Research, covering District Court, S.D. California primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Keszthelyi v. Doheny Stone Drill Co., 47 F.2d 648, 1931 U.S. Dist. LEXIS 1177 (S.D. Cal. 1931).

Opinion

COSGRAVE, District Judge.

On November 20,1923, letters patent No. 1,474,905 were issued to plaintiff for a new and useful improvement in tool joints used in rotary drilling of oil wells.

Plaintiff explains in his specifications that in rotary drilling the bit cutting the formation is carried at the lower end of the string of drill pipe. To withdraw the bit it is necessary to pull the drill pipe, uncoupling it at intervals, ordinarily of four lengths of the pipe. As the pipe is drawn from the well it is therefore uncoupled at every fourth joint, and it is therefore necessary to provide a tool joint at such.intervals to prevent the injuring of the threads of the pipe by frequent coupling and uncoupling.

That in rotary drilling it is necessary to circulate a stream of mud-laden fluid down through the string of drill pipe and through the bit. To do this it is necessary to apply considerable pressure to the upper end of the drill pipe, and it is difficult, using the present type of tool joint, to insure tight joints at the ends of the stands of drill pipe.

That tool joints, as ordinarily constructed, consist of a pair of steel collars, one of which is screwed upon each of the contacting ends of the drill pipe, using the threads with which the pipe is ordinarily provided. One of the collars has a pipe with a steep taper and coarse threads, and the other collar having a box into which this pipe or pin is threaded. It is the common practice to set up these tool joints by the use of the power driven rotary table so that the friction on the threads between the box and the pin is very great, and it is not an uncommon thing for the joints to become loose or even unscrewed.

He further states that “it is an object of my invention to provide a novel form of tool joint in which the friction on the threads is not entirely depended upon to hold the joint together but supplemental frictional means are provided for this purpose.” Then, after referring to the mud circulating feature above mentioned, he says: “It is a further object of my invention to provide auxiliary means of insuring a tight joint at all times.” Further objects and advantages will be made evident hereinafter.

By reference to the drawings he shows the upper or primary collar screwed to the end of the section of drill pipe. Formed in the primary collar is an outer lip, the outside lower edge or shoulder of which is flat, at a right angle to the axis of the pipe. The inside of the lip is conical, the conical surface terminating in a groove at the inside base of which begins a projection extending downward and externally threaded with a coarse tapered thread, and this projection terminates in a flat nose or radial surface, fitting into a groove in the secondary collar. The lower or secondary collar is screwed to the upper end of the lower section of drill pipe. It has an outside shoulder with radial surface facing that on the lip of the primary collar. Then a projection on the secondary collar commences with an external conical surface of proper taper and size to fit into the inside conical face of the lipon the primary collar as the joint is screwed home. This projection on the lower or secondary collar terminates in a flat nose, at • a right angle to the axis of the pipe, and facing the groove described in the primary collar, the surface of the nose being wider than the bottom of the groove. The inside of the projection on the secondary collar is threaded to receive the threaded projection on the primary collar, and at the inside base of the projection on the secondary collar, is a groove [649]*649into which the radial surface or nose of the projection on the primary collar faces.

Between all radial faces, that is, faees at a right angle to the axis of the pipe, a small space is shown. The patent specifies that “the parts are so proportioned that when the collars are screwed home there is still a little space therebetween on .all surfaces which are at right angles to the axis of the pipe.”

The plaintiff in his specifications continues :

“In this preferred form of my invention it is possible to obtain a very tight joint between the collars * * * due to the tapered lip (of the primary collar) which cooperates with its complementary part on the (secondary) collar. This tapered surface not only acts to produce a tight joint independent of the threads between the parts, but it also tends to increase the friction between the two collars * * * thus preventing the joints from becoming unscrewed. The central projection (not heretofore mentioned because deemed unimportant by all parties) also serves to insure a tight joint between the parts although this may in some eases be omitted and entire reliance placed on the „ conical surface.”

He then desires that his invention “shall be defined solely by the annexed claims.” His claims are:

“1. A tool joint comprising: a primary collar adapted to be secured to a joint of pipe and having an opening therethrough, said opening being in open communication with the interior of said pipe; a secondary collar adapted to be secured to a joint of pipe and having an opening therethrough, said opening being in open communication with the interior of said pipe; a lip formed on the outer edge of said primary collar and enclosing a groove; a projecting portion of said secondary collar fitting inside said groove and inside said lip; and threaded means for forcing said collar towards each other in an axial direction.

“2. A tool joint as in claim 1 in which the interior surface of said lip is conical and the projecting portion of said secondary collar fitting inside said conical surface is also coned to fit in fluid tight relationship therein.”

“5. A tool joint comprising: a primary collar adapted to be secured to a joint of pipe and having an opening therethrough in open communication with the interior of said pipe a secondary collar adapted to be secured to a joint of pipe and having an opening there-through in open communication with the interior of said pipe and with the opening in said primary collar; a lip formed on the outer edge of said primary collar and enclosing a groove; a projecting portion of said secondary collar fitting inside said groove and inside said lip; a conical projection having an external thread and formed centrally on said primary collar; and an internally threaded portion on said secondary collar into which said projection fits and is threaded.”

The other claims are omitted, as it is conceded that only 2 and 5 are important.

It appears therefore that plaintiff claims as his invention the tool joint consisting of the two collars described with threaded means of closing the joint where the lip of the primary collar is beveled or coned to receive the projecting portion of the secondary collar, which is also coned to fit in fluid tight relationship.

In other words, the outside lip with the interior beveled or coned surface receiving a similarly beveled projection on the complementary part and forced into fluid tight relationship by the threads.

The patent seeming to depend on the conical or beveled contacting surfaces is clearly anticipated by the Runyan patent, No. 1,-394,791, issued in .1921, whore the beveled surfaces are described as relieving the threads of strain and consequent wear, and distinctly claimed. Substantially the same principle is shown by the patent to Lecky, No. 47,554, issued in 1865. This was before the day of rotary drilling.

Free access — add to your briefcase to read the full text and ask questions with AI

Related

Railroad Co. v. Mellon
104 U.S. 112 (Supreme Court, 1881)

Cite This Page — Counsel Stack

Bluebook (online)
47 F.2d 648, 1931 U.S. Dist. LEXIS 1177, Counsel Stack Legal Research, https://law.counselstack.com/opinion/keszthelyi-v-doheny-stone-drill-co-casd-1931.