Thread arrangement for earth boring members

Claim 2

A thread configuration for the pin and box of shafts for connecting the shafts together, said thread configurations having the following characteristics: a. thread lead O.D. divided by about 10; b. pin neck length O.D. divided by about 7.25; c. thread height O.D. divided by about 40; d. thread root radius thread height divided by about two; e. thread crest length thread height divided by about two; f. pin overall length O.D. multiplied by about 0.8; g. thread taper (O.D.- I.D.) and this divided by about two times O.D.; h. angle between flanks about 75* to about 100*; i. load flank angle relative to axis of shaft about 50* to about 70*; j. stabbing flank angle relative to axis of shaft about 20* to about 40*; k. pitch diameter about 0.700 to about 0.800 of diameter; l. nose diameter about 0.625 to about 0.700 of diameter; m. pin neck diameter about 0.750 to about 0.800 of diameter; n. wherein O.D. is the outer diameter of the shafts; o. wherein thread lead is the number of threads per inch; p. wherein pin neck length is the length of the cylindrical surface on the pin from the end of the threads to the shoulder on the pin; q. wherein thread height is the vertical distance from the root to the crest of the thread; r. wherein pin overall length is the length of the pin from said shoulder to the end of the pin; s. wherein I.D. is the internal diameter of any bore extending through the shafts; t. wherein thread taper is represented by a line in a plane tangent to the crests of the threads on the pin and box and its angular relationship to the longitudinal axis of the shafts; u. wherein pitch diameter is average of diameter of crest of thread and average diameter of root of thread divided by 2; v. wherein the angle between the flanks is the angle between two adjacent, opposed surfaces of a thread; w. wherein the load flank is the surface of the thread on the pin which engages a similar thread surface on the box when the pin and box of the shafts are made up; and x. wherein the stabbing flank is the surface of the thread on the pin which is not engaged with a similar thread surface on the box when the pin and box of the shafts are made up.

Claim 3

A threaded connection for shafts comprising: a. a box of at least one end of one of the shafts; b. a pin on at least one end of another shaft, said pin and box having a conforming thread configuration whereby adjacent shaft ends may be connected together by threadedly engaging the pin of one of said shafts in the box of the other shaft; c. said pin including a shoulder projecting inwardly from the outer diameter of the shaft; d. a cylindrical neck extending longitudinally from said shoulder and on smaller diameter than the outer diameter of said shaft; e. a threaded portion on said pin and extending longitudinally from said cylindrical neck an unthreaded cylindrical nose extending longitudinally from said threaded portion; f. said box having an unthreaded portion adjacent its outer end which is in spaced relation to said cylindrical neck on said pin when said pin and box are made up to provide an annular space adjacent the outer end of said box between said pin and box when they are made up; g. a threaded portion extending from said unthreaded portion into said box; h. said box having an unthreaded portion adjacent and extending longitudinally from said threaded portion in said box and being in spaced relation to at least a portion of said cylindrical nose on said pin when said box and pin are threadedly made up to provide an annular space adjacent the inner end of said box between said pin and box when they are made up; i. said threaded portion on said pin and box being tapered and each thread having two adjacent flanks, one of said flanks on said Pin for contacting a similar flank on said box when said pin and box are stabbed together to be made up, and the other of said flanks on said pin engaging a similar flank on said box to transmit load in said connection when said pin and box are made up; j. said flanks on said threads on said pin which engage said flanks on said threads on said box when said pin and box are stabbed together to be made up being in spaced relation when said pin and box are made up to form a helical void therebetween when said pin and box are connected together; k. the crests of said threads in said pin and said box being flat and having a predetermined length; l. the roots of said threads in said pin and box being formed on a radius which is tangent to the thread flanks which said roots join together whereby said flat crests of said threads are in spaced relation to said roots when said pin and box are made up to form a void which communicates with the void formed between said stabbing flanks when said pin and box are made up; and m. said annular spaces adjacent the inner end and outer end of said box communicating with said voids whereby contamination on said pin and box may be extruded thereinto as said pin and box are made up.

Claim 4

A threaded connection for shafts comprising: a. a box of at least one end of one of the shafts; b. a pin on at least one end of another shaft, said pin and box having a conforming thread configuration whereby adjacent shaft ends may be connected together by threadedly engaging the pin of one of said shafts in the box of the other shaft; c. said pin including a shoulder projecting inwardly from the outer diameter of the shaft; d. a cylindrical neck extending longitudinally from said shoulder and on smaller diameter than the outer diameter of said shaft; e. a threaded portion on said pin and extending longitudinally from said cylindrical neck an unthreaded cylindrical nose extending longitudinally from said threaded portion; f. said box having an unthreaded portion adjacent its outer end which is in spaced relation to said cylindrical neck on said pin when said pin and box are made up to provide an annular space adjacent the outer end of said box between said pin and box when they are made up; g. a threaded portion extending from said unthreaded portion into said box; h. said box having an unthreaded portion adjacent and extending longitudinally from said threaded portion in said box and being in spaced relation to at least a portion of said cylindrical nose on said pin when said box and pin are threadedly made up to provide an annular space adjacent the inner end of said box between said pin and box when they are made up; i. said threaded portion on said pin and box being tapered and each thread having two adjacent flanks, one of said flanks on said Pin for contacting a similar flank on said box when said pin and box are stabbed together to be made up, and the other of said flanks on said pin engaging a similar flank on said box to transmit load in said connection when said pin and box are made up; j. said flanks on said threads on said pin which engage said flanks on said threads on said box when said pin and box are stabbed together to be made up being in spaced relation when said pin and box are made up to form a helical void therebetween when said pin and box are connected together; k. the crests of said threads in said pin and said box being flat and having a predetermined length; l. the roots of said threads in said pin and box being formed on a radius which is tangent to the thread flanks which said roots join together whereby said flat crests of said threads are in spaced relation to said roots when said pin and box are made up to form a void which communicates with the void formed between said stabbing flanks when said pin and box are made up; and m. said annular spaces adjacent the inner end and outer end of said box communicating with said voids whereby contamination on said pin and box may be extruded thereinto as said pin and box are made up.

Claim 5

The invention of claim 2 wherein said shafts are solid.

Claim 6

The invention of claim 2 wherein said shafts are provided with an internal bore therethrough.

Claim 7

The invention of claim 2 wherein said thread configuration on said pin and box has the following characteristics: a. thread lead O.D. divided by about 10; b. pin neck length O.D. divided by about 7.25; c. thread height O.D. divided by about 40; d. thread root radius thread height divided by about 2; e. thread crest length thread height divided by about two; f. pin overall length O.D. multiplied by 0.8; g. thread taper (O.D.- I.D.) divided by about two multiplied by O.D.; h. angle between flanks about 75* to about 100*; i. load flank angle relative to axis of shaft about 50* to about 70*; j. stabbing flank angle relative to axis of shaft about 20* to about 40*; and k. wherein O.D. is the outer diameter of the shaft.

Claim 8

The invention of claim 1 wherein said box has an unthreaded cylindrical portion extending from said unthreaded portion next to said threaded portion for receiving said cylindrical nose of said pin when pin and box are threadedly made up.

Claim 9

A thread configuration for the pin of a shaft having the following characteristics: a. thread lead O.D. divided by about 10; b. pin neck length O.D. divided by about 7.25; c. thread height O.D divided by about 40; d. thread root radius thread height divided by about two; e. thread crest length thread height divided by about two; f. pin overall length O.D. multiplied by about 0.8; g. thread taper (O.D.- I.D.) and this divided by about two times O.D.; h. angle between flanks about 75* to about 100*; i. load flank angle relative to axis of shaft about 50* to about 70*; j. stabbing flank angle relative to axis of shaft about 20* to about 40*; k. pitch diameter about 0.700 to about 0.800 of diameter; l. pin neck diameter about 0.750 to about 0.800 of diameter; m. wherein O.D. is the outer diameter of the shaft; n. wherein thread lead is the number of threads per inch; o. wherein pin neck length is the length of the cylindrical surface on the pin from the end of the threads to the shoulder on the pin; p. wherein thread height is the vertical distance from the root to the crest of the thread; q. wherein pin overall length is the length of the pin from said shoulder to the end of the pin; r. wherein I.D. is the internal diameter of any bore extending through the shaft; and s. wherein thread taper is represented by a line in a plane tangent to the crests of the threads on the pin and its angular relationship to the longitudinal axis of the shaft.

Claim 10

A thread configuration for the pin of a shaft having the following characteristics: a. thread lead O.D. divided by about 10; b. pin neck length O.D. divided by about 7.25; c. thread height O.D divided by about 40; d. thread root radius thread height divided by about two; e. thread crest length thread height divided by about two; f. pin overall length O.D. multiplied by about 0.8; g. thread taper (O.D.- I.D.) and this divided by about two times O.D.; h. angle between flanks about 75* to about 100*; i. load flank angle relative to axis of shaft about 50* to about 70*; j. stabbing flank angle relative to axis of shaft about 20* to about 40*; k. pitch diameter about 0.700 to about 0.800 of diameter; l. pin neck diameter about 0.750 to about 0.800 of diameter; m. wherein O.D. is the outer diameter of the shaft; n. wherein thread lead is the number of threads per inch; o. wherein pin neck length is the length of the cylindrical surface on the pin from the end of the threads to the shoulder on the pin; p. wherein thread height is the vertical distance from the root to the crest of the thread; q. wherein pin overall length is the length of the pin from said shoulder to the end of the pin; r. wherein I.D. is the internal diameter of any bore extending through the shaft; and s. wherein thread taper is represented by a line in a plane tangent to the crests of the threads on the pin and its angular relationship to the longitudinal axis of the shaft.

Claim 11

The invention of claim 8 wherein said shaft is solid.

Claim 12

The invention of claim 8 wherein said shaft is provided with an internal bore therethrough.

Claim 13

The invention of claim 8 wherein there is an unthreaded cylindrical nose extending from said threaded portion on said pin to the end of said shaft.

Claim 14

A thread configuration for the box of a shaft having the following characteristics: a thread lead O.D. divided by about 10; b. thread height O.D. divided by about 40; c. thread root radius thread height divided by about two; d. thread crest length thread height divided by about two; e. thread taper (O.D.- I.D.) and this divided by about two times O.D.; f. angle between flanks about 75* to about 100*; g. load flank angle relative to axis of shaft about 50* to about 70*; h. stabbing flank angle relative to axis of shaft about 20* to about 40*; i. pitch diameter about 0.700 to about 0.800 of diameter; j. wherein O.D. is the outer diameter of the shaft; k. wherein thread lead is the number of threads per inch; l. wherein thread height is the vertical distance from the root to the crest of the thread; m. wherein I.D. is the internal diameter of any bore extending through the shaft; and n. wherein thread taper is represented by a line in a plane tangent to the crests of the threads on the box and its angular relationship to the longitudinal axis of the shaft.

Claim 15

A thread configuration for the box of a shaft having the following characteristics: a thread lead O.D. divided by about 10; b. thread height O.D. divided by about 40; c. thread root radius thread height divided by about two; d. thread crest length thread height divided by about two; e. thread taper (O.D.- I.D.) and this divided by about two times O.D.; f. angle between flanks about 75* to about 100*; g. load flank angle relative to axis of shaft about 50* to about 70*; h. stabbing flank angle relative to axis of shaft about 20* to about 40*; i. pitch diameter about 0.700 to about 0.800 of diameter; j. wherein O.D. is the outer diameter of the shaft; k. wherein thread lead is the number of threads per inch; l. wherein thread height is the vertical distance from the root to the crest of the thread; m. wherein I.D. is the internal diameter of any bore extending through the shaft; and n. wherein thread taper is represented by a line in a plane tangent to the crests of the threads on the box and its angular relationship to the longitudinal axis of the shaft.

Claim 16

The invention of claim 12 wherein said shaft is solid.

Claim 17

The invention of claim 12 wherein said shaft is provided with an internal bore therethrough.

Claim 18

The invention of claim 12 wherein there is n unthreaded cylindrical nose extending from said threaded portion on said pin to the end of said shaft.