US2804948A - Telescoping portable mast - Google Patents
Telescoping portable mast Download PDFInfo
- Publication number
- US2804948A US2804948A US382342A US38234253A US2804948A US 2804948 A US2804948 A US 2804948A US 382342 A US382342 A US 382342A US 38234253 A US38234253 A US 38234253A US 2804948 A US2804948 A US 2804948A
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- US
- United States
- Prior art keywords
- legs
- section
- upper section
- lower section
- mast
- Prior art date
- 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.)
- Expired - Lifetime
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- 210000002414 leg Anatomy 0.000 description 167
- 210000002105 tongue Anatomy 0.000 description 8
- 230000005484 gravity Effects 0.000 description 5
- 239000003129 oil well Substances 0.000 description 2
- 210000001364 upper extremity Anatomy 0.000 description 2
- 210000000689 upper leg Anatomy 0.000 description 2
- 241000364021 Tulsa Species 0.000 description 1
- 238000004873 anchoring Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 238000012384 transportation and delivery Methods 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B15/00—Supports for the drilling machine, e.g. derricks or masts
Definitions
- This invention relates to portable oil well drilling masts, and more particularly to a mast which can be swung from ⁇ an upright position down to a reclining position for transp ⁇ ortation.
- the mast has an open front and an upwardly tapered upper section mounted on a lower section.
- the mast is adapted to be swung from upright position backward to reclining position along the ground.
- the lower section In reclining position the lower section has a pair of parallel upper legs and a pair of lower legs, preferably extending backward beyond them.
- the upper section has legs in end to end relation with the legs of the lower section.
- the front ends of the upper section legs are detachably connected to the rear ends of the lower section legs by splicing means, which most suitably include drive pins pivotally connected to arms that are hinged to the mast so that the pins cannot get away when removed from the splices.
- splicing means which most suitably include drive pins pivotally connected to arms that are hinged to the mast so that the pins cannot get away when removed from the splices.
- 'A cooperating ramp and rampengaging member, preferably a roller, below the mast sections are substantially in engagement with each other and are supported by
- the ramp and roller are positioned to raise the front ends of the upper section legs above the corressections.
- Fig. l is a miniature view of the front of the upright mast
- Fig. 2 is an enlarged side view of the mast after it has been lowered to reclining position
- Fig. 3 is a view similar to the preceding figure, but showing the upper section of the mast telescoped into the lower section;
- Fig. 4 is an enlarged fragmentary cross section taken on the line IV--IV through the far side of the mast in Fig. 3;
- Fig. 5 is an enlarged side view of the reclining mast at the connection between its upper and lower sections;
- Fig. 6 is a view similar to the preceding figure, but showing the upper section starting to move back into the lower section;
- Fig. 7 is an enlarged fragmentary section taken on the line VIIVII of Fig. 6;
- Fig. 8 is a plan view of the reclining mast at the connection between its two sections, with parts broken away;
- Figs. 9 and 10 are enlarged fragmentary vertical sections taken on the lines IX-IX and X-X, respectively, of Fig. 8.
- the front of our mast is shown in outline in Fig. 1, mounted in upright operative position on suitable supports 1.
- This mast is formed in two sections that are detachably connected together; an upper one 2 that is tapered upwardly, and a lower one 3 whose front legs are substantially parallel from their upper ends most of the way down.
- the sides and back of the mast are braced, but the front is open so that drill pipe can be swung in and out of it.
- the lower end of the mast is hinged to the supports so that the mast can be swung backward and down into a substantially horizontal reclining position, as shown in Fig. 2, in a well known manner.
- the front legs of the upright mast become the upper legs of the reclining mast, and the back legs of the upright mast become the lower legs of the prone mast.
- the lower legs 4 of the lower section 3 extend backward several feet beyond its upper legs 5, and that the upper legs 7 of the upper section 2 extend forward beyond its lower legs 8.
- the two sections of the mast therefore overlap along an inclined plane.
- the rear ends of the upper legs 5 of the lower section are provided with tongues 10 that extend into forks 11 at the front endsv of the upper legs 7 of the upper section. These tongues and forks are provided .with aligned holes, into which splice pins 12 are driven.
- lower legs 8 of the upper section are provided with tongues 13 that project into forks 14 on the rear ends of the lower legs 4 of the lower section, and these tongues and forks are rigidly connected by splice pins 15, driven through them.
- the upperlegs of each recliningsection of the mast are formed from angle bar-shaving upper flanges Also, the front ends of the It will be observed that the pinned connections are so positioned between the adjoining legs that the legs projecting outward away from each other.
- the lower legs may take any suitable form, those illustrated being tubular.
- the ramp-engaging member be a roller and be supported by the lower section and that the ramps be supported by the upper section so that the ramps will run up the roller.
- the rear ends of the upper legs of the lower section of the mast are connected by inclined braces 17 to short inclined channels 18 that extend behind and below lower forks 14.
- the lower ends of these channels are rigidly connected by a cross member 19, behind which a horizontal roller 20 is journaled in the channels. As shown in Figs. and 10, this roller extends across the mast in engagement with the bottom of the front end of the upper section a short distance behind tongues 13.
- the ramps 21 are secured to the lower legs 8 of the upper section directly behind the roller.
- a pair of track plates 22 which are in line with the vertical flanges of those legs.
- the plates are provided with forwardly opening recesses 23 having horizontal lower walls and upper walls that form tracks inclined upward and forward to the vertical flanges of the legs above. Fitting in these recesses are grooved wheels 24 journaled in the lower ends of triangular plates 25 that extend downward and forward from I the upper leg forks 1-1 of the upper mast section.
- These triangular plates are between track plates 22 and are provided with holes through which connecting pins 12 extend.
- Telescoping of the sections can be accomplished in any suitable manner, such as by a line attached to the upper section and to the cathead 27 (Fig. 3), or by anchoring the traveling block 28 (Fig. l) in the lower section and then operating the drawworks hoist (not shown) to reel in the line 29 on which the block is strung.
- rollers 32 move up inclined bars 34 fastened to the rear ends of upper tongues 10. Due to section is not raised above the lower section legs until ramp-like frame 35 at the crown rides up onto roller 20/ as shown in Fig. 3.
- a sling line 36 To untelescope or extend the mast the opposite ends of a sling line 36 are attached to anchor brackets ⁇ 37 projected forward from the bottom of upper section? 2 between its legs, as shown in Figs. 8 and 10.
- This line extends back and down around vertical sheaves 38 fitstened to the front of cross member 19 between channels 18, and then forward around a pair of horizontal sheaves 39 also fastened to the cross member.
- the upper section 2 will be pulled out of the lower section 3 until ramps 21 reach the roller, and then the upper section will move downward as well as backward to final position, in which the cooperating forks and tongues will be in positions to receive the splice pins 12 and 15. As soon as these pins are driven into place, the extended mast is ready to be raised.
- this mast can be extended while reclining, so that good tight connections can be made between the two sections by workmen working close to V the ground. They do not have to climb an upright mast to connect or disconnect the sections, and the use of automatically operating latches is avoided. Consequently, the mast is rigid enough to make guy wires unnecessary.
- the end to end relation ofthe connected legs also adds to the strength and rigidity of the mast and saves material that would be required if the legs overlapped;
- Another feature of this invention is that the splice pin 12 and 15 at the joint between the two sections of the mast are permanently connected to the mast so that they will not become mislaid or lost and so that when they are driven'out of the forks they will not fly through the air and possibly injure someone.
- pins 12 are between the opposite sides of the mast, and each is provided with trunnions 41 loosely mounted in longitudinal slots in one of the bifurcated ends of a channel-like arm 42, as shown in Figs. 8 and 9.
- the arm extends along the inner surface of the adjacent triangular plate 25 to a point near grooved wheel 24, where the arm is pivotally mounted between the ends of a pair of reinforcing bars 43 and 44 welded to the inner surface of the plate.
- a coil spring 45 fastened to bar 44 and the side of the arm, pulls the arm toward the plate.
- each pin is provided with trunnions 51 loosely mounted in slots in one of the bifurcated ends of a channel-like arm 52, as shown in Figs. 5 and 8.
- the opposite end of the arm is pivotally mounted in a bracket 53 welded to the outside of the adjoining leg 4 of the mast.
- a coil spring 54 is stretched between the bracket and the side of the arm to pull the arm toward the leg. The arm holds the splice pin in driving position and after it has been driven out of the leg splice, and forms a convenient housing for the pin when it is not in use, as
- An open front portable mast having a lower section anfd a'n upwardly tapered upper section and adapted to be swiung from upright position backward to reclining positidn, said lower section in its reclining position having a ipair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legsof the lower section, splicing means detachably connecting the front ends of the reclining upper section legs to the rear ends of the lower section legs, a cooperating ramp and ramp-engaging member substantially in engagement with each other below said sections and supported by their adjoining ends, the ramp and ramp-engaging member being positioned to raise the front ends of the upper section legs above the corresponding lower section legs when said reclining sections are disconnected at said splicing means and the upper section is moved forward, whereby to telescope the mast, and anti-friction members carried by the front end of the upper part of the reclining upper section and engageable with the upper and lower surfaces of said upper legs of the reclining lower section as the mast is
- An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legs of the lower section, splicing means detachably connecting the front ends of the reclining upper section legs to the rear ends of the lower section legs, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, and short ramps secured to the bottom of the reclining upper section and extending downward and backward therefrom behind said support substantially in engagement therewith, whereby when said reclining sections are disconnected at said splicing means and the upper section is moved forward said transverse support and ramps will raise the front ends of the upper section legs above the corresponding lower section legs to permit the upper section to be telescoped into the lower section.
- An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining posi- 6 tion, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs extending backward beyond the upper legs, said upper section in its reclining position having a pair of lower legs in end to end relation with the lower legs of the lower section and having a pair of upper legs extending forward beyond its lower legs and in end to end relation with the upper legs of the lower section, splicing means detachably connecting the front ends of the upper section legs to the rear ends of the lower section legs, whereby the front end of the upper section normally overlaps the rear end.of the lower section, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, and short ramps secured to the bottom of the reclining upper section and extending downward and backward behind said support substantially in engagement therewith, whereby when said reclining sections are disconnected at said splicing means
- An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legs of the lower section, splicing means detachably connecting the front ends of the upper section legs to the rear ends of the lower section legs, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, short ramps secured to the bottom of the reclining upper section and extending downward and backward behind said support substantially in engagement therewith, whereby when said reclining sections are disconnected at said splicing means and the upper section is moved forward said transverse support and ramps will raise the front ends of the upper section legs above the corresponding lower section legs and means then holding the front ends of the upper legs of the upper section a predetermined distance above the lower section so that the upper section can be telescoped into the lower section.
- An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legs of the lower section, splicing means detachably conmeeting the front ends of the upper section legs to the rear ends of the lower section legs, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, short ramps secured to the botttom of the reclining upper section and extending downward and backward behind said support substantially in engagement therewith, whereby when said reclining sections are disconnected at said splicing means and the upper section is moved forward said transverse support and ramps will raise the front ends of the upper section legs above the corresponding lower section legs, and means carried by the upper section for supporting the front ends of its upper legs above the lower section after the center of gravity of the upper section has moved forward past said transverse support
- An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs extending backward beyond the upper legs, said upper sec- 7 tion in its reclining position having a pair of lower legs in end to end relation with the lower legs of the lower section and having a pair of upper legs extending forward beyond its lower legs and in end to end relation with the upper legs of the lower section, splicing means detachably connecting the front ends of the upper section legs to the rear ends of the lower section legs, whereby the front end of the upper section normally overlaps the rear end of the lower section, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, short ramps secured to the bottom of the reclining upper section and extending downward and backward behind said support substantially in engagement therewith, and wheels carried by the upper section of the mast at such distance below the upper legs of the
- An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legs of the lower section, splicing means detachably connecting the front ends of the upper section legs to the rear ends of the lower section legs, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, short ramps securedto the bottom of the reclining upper section and extending downward and backward behind said support substantially in engagement therewith, whereby when said reclining sections are disconnected at said splicing means and the upper section is moved forward said transverse support and ramps will raise the front ends of the upper section legs above the corresponding lower section legs so that the upper section can be telescoped into the lower section, means carried by the upper section of the mast for then engaging the lower surface of the upper legs of said lower section to limit upward movement of
- An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legs of the lower section, splicing means detachably connecting the front ends of the reclining upper section legs to the rear ends of the lower section legs, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, short ramps secured to the bottom of the reclining upper section and extending downward and backward behind said support substantially in engagement therewith, wheels carried by the upper section of the mast below the upper splicing means, and tracks inclined from the upper legs of the lower section downward and backward over the wheels substantially in engagement therewith, whereby when said reclining sections are disconnected at said splicing means and the upper section is moved forward said transverse support and ramps will raise the upper section legs above the corresponding lower section legs as the wheels run
- An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs, and a pair of lower legs extending backward beyond the upper legs, said parallel legs having downwardly extending flanges, said upper section in its reclining position having a pair of lower legs in end to end relation with the lower legs of the lower section and having a pair of upper legs extending forward beyond its lower legs and in end to end relation with the upper legs of the lower section, splicing means detachably connecting the front ends of the upper section legs to the rear ends of the lower section legs, whereby the front end of the upper section normally overlaps the rear end of the lower section, a horizontal roller carried b the rear end of the reclining lower section transverseg thereof substantially in engagement with the bottom f the upper section, short ramps secured to the bottomi-of the reclining upper section and extending downward agld backward behind the roller substantially in engagement there
- An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to recliniing position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legs of the lower section, the adjacent ends of the legs having interfitting portions provided with aligned transverse holes, splice pins in said holes detachably connecting the front ends of the reclining upper section legs to the rear ends of the lower section legs, an arm pivotally connected at one end to each pin, means pivotally connecting the opposite end of the arm to the mast, a cooperating ramp and rampengaging member substantially in engagement with each other below said sections and supported.
- the ramp and ramp-engaging member being positioned to raise the front ends of the upper section legs above the corresponding lower, section legs when said reclining sections are disconnected at said splicing means and the upper section is moved forward, whereby to telescope the mast.
- each pin-supporting arm is channellike and has its open side facing the mast and adapted to receive the pin after it has been removed from said holes, and a spring urging said first-mentioned end of the arm toward the mast,
- An open front portable oil well mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position down to reclining position, said lower section in its reclining position having a pair of upper legs and a pair of lower legs, the pair of legs at the open front of the lower section being substantially parallel, said upper section having legs in end to end relation with the legs of the lower section, splicing means detachably connecting the upper section legs to the lower section legs, means for moving the reclining upper section toward the lower section after the reclining sections are disconnected at said splicing means, and means for guiding the reclining upper section vertically toward the open front of the reclining lower section as the upper section is first moved toward the lower section, whereby to move the legs of the two sections out of end to end relation to permit the upper section to telescope into the lower section, the reclining mast being provided with vertically spaced track surfaces extending lengthwise thereof and with anti-friction members above and below said surfaces and engageable with them as the mast is telescoped, whereby to hold the reclining
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Description
Sept. 3, 1957 H. J. WOOLSLAYER ET AL 2,804,948
TELESCOPING PORTABLE MAST 3 Sheets-Sheet l Filed Sept. 25, 1955 Jam;
EAL.
8 m. N 4 4 n Maw n M w v? e r. w N wy i Z Z p 1957 H. J. WOOLSLAYER ET AL 2,804,948
TELESCOPING PORTABLE MAST 3 Sheets-Sheet 2 Filed Sept. 25, 1953 p 1957 H. J. WOOLSLAYER ET AL 2,804,948
TELESCOPING PORTABLE MAST 3 Sheets-Sheet 3 Filed Sept. '25, 1955 INVEN TOR$ mya male flnvm ar United States Patent if TELESCOPING PQRTABLE MAST Homer J. Woolslayer and Cecil Jenkins, Tulsa, Okla, and Erwin A. Campbell, Wexford, Pa., assignors to Lee C. Moore Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Application September 25, 1953, Serial No. 382,342
14 Claims. (Cl. 189-11) This invention relates to portable oil well drilling masts, and more particularly to a mast which can be swung from \an upright position down to a reclining position for transp\ortation.
\Such masts are well known. They are made ready for tra sportation to another location either by separating them into independent sections or by telescoping them. Her' etofore, the telescoping and extending of the masts have generally been accomplished in the erect position. The upper section was narrower than the lower section sof that the former could slide into the latter. This made it lnecessary to have considerable overlap of the adjoining legs in the extended position. To make it unnecessaty for workmen to climb the erect mast and bolt or pin the extended sections tightly together, latches have been used which operated automatically when the uppersection was raised. However, latches do not connect the sections together tightly enough, so guy wires have been required in order to enable the upright mast to resist wind loads. Furthermore, strain was placed on the legs of the mast due to the eccentric loading caused by the upper legs being offset inwardly relative to the lower legs instead of being in line with them.
It is among the objects of this invention to provide a telescoping portable mast which can be extended and telescoped while in reclining position, which has the lower ends of the legs of its upper section detachably fastened to the upper ends of the legs of its lower section, which utilizes rigid splices between the sections, which does not require guy wires to steady it when it is in upright Operative position, and in which the splice pins at the joint are permanently connected to the mast and held in position for driving into place.
In accordance with this invention the mast has an open front and an upwardly tapered upper section mounted on a lower section. The mast is adapted to be swung from upright position backward to reclining position along the ground. In reclining position the lower section has a pair of parallel upper legs and a pair of lower legs, preferably extending backward beyond them. The upper section has legs in end to end relation with the legs of the lower section. The front ends of the upper section legs are detachably connected to the rear ends of the lower section legs by splicing means, which most suitably include drive pins pivotally connected to arms that are hinged to the mast so that the pins cannot get away when removed from the splices. 'A cooperating ramp and rampengaging member, preferably a roller, below the mast sections are substantially in engagement with each other and are supported by the adjoining ends of the mast.
The ramp and roller are positioned to raise the front ends of the upper section legs above the corressections.
ponding lower section legs when the reclining sections of the masts are disconnected at the splice and the upper section is moved forward. Means also are provided for holding the front ends of the upper legs of the upper section above the lower section as the upper section is tele-- scoped into the lower section. Furthermore, there are f 2,804,948 fi Patented'Sept. 3, 1957 means for preventing the front end of the upper section from tilting up more than a predetermined distance while it is moving forward.
The preferred embodiment of the invention is illustrated in the accompanying drawings, in which Fig. l is a miniature view of the front of the upright mast;
Fig. 2 is an enlarged side view of the mast after it has been lowered to reclining position;
Fig. 3 is a view similar to the preceding figure, but showing the upper section of the mast telescoped into the lower section;
Fig. 4 is an enlarged fragmentary cross section taken on the line IV--IV through the far side of the mast in Fig. 3;
Fig. 5 is an enlarged side view of the reclining mast at the connection between its upper and lower sections;
Fig. 6 is a view similar to the preceding figure, but showing the upper section starting to move back into the lower section;
Fig. 7 is an enlarged fragmentary section taken on the line VIIVII of Fig. 6;
Fig. 8 is a plan view of the reclining mast at the connection between its two sections, with parts broken away; and
Figs. 9 and 10 are enlarged fragmentary vertical sections taken on the lines IX-IX and X-X, respectively, of Fig. 8.
Referring to the drawings, the front of our mast is shown in outline in Fig. 1, mounted in upright operative position on suitable supports 1. This mast is formed in two sections that are detachably connected together; an upper one 2 that is tapered upwardly, and a lower one 3 whose front legs are substantially parallel from their upper ends most of the way down. The sides and back of the mast are braced, but the front is open so that drill pipe can be swung in and out of it. The lower end of the mast is hinged to the supports so that the mast can be swung backward and down into a substantially horizontal reclining position, as shown in Fig. 2, in a well known manner. The front legs of the upright mast become the upper legs of the reclining mast, and the back legs of the upright mast become the lower legs of the prone mast. it will be observed that in the illustrated embodiment the lower legs 4 of the lower section 3 extend backward several feet beyond its upper legs 5, and that the upper legs 7 of the upper section 2 extend forward beyond its lower legs 8. The two sections of the mast therefore overlap along an inclined plane. v
To connect the two mast sections together, the rear ends of the upper legs 5 of the lower section are provided with tongues 10 that extend into forks 11 at the front endsv of the upper legs 7 of the upper section. These tongues and forks are provided .with aligned holes, into which splice pins 12 are driven. lower legs 8 of the upper section are provided with tongues 13 that project into forks 14 on the rear ends of the lower legs 4 of the lower section, and these tongues and forks are rigidly connected by splice pins 15, driven through them.
of the upper section are in end to end relation with those of the lower section; that-is, the legs of the upper sectwo sections therefore are the same width, but the rest of the tapered upper section is narrower than the lower section. The upperlegs of each recliningsection of the mast are formed from angle bar-shaving upper flanges Also, the front ends of the It will be observed that the pinned connections are so positioned between the adjoining legs that the legs projecting outward away from each other. The lower legs may take any suitable form, those illustrated being tubular.
To permit the reclining upper section to be telescoped into the lower section so that the mast can be shortened for transportation, it is necessary that the upper section be raised enough for the front ends of its legs to clear the parallel legs of the lower section. This is accomplished by a cooperating ramp or ramps and rampenga'ging member .that are substantially in engagement with each other below the mast sections. The ramps and ramp-engaging member are supported by the adjoining ends of those sections. The ramps are inclined downward and backward so that when the reclining upper section 2 is pulled forward, after being disconnected from the lower section, the movement of the ramps and rampengaging member against each other will raise the front end of the upper section, as shown in Fig. 6. It is preferred that the ramp-engaging member be a roller and be supported by the lower section and that the ramps be supported by the upper section so that the ramps will run up the roller. Accordingly, the rear ends of the upper legs of the lower section of the mast are connected by inclined braces 17 to short inclined channels 18 that extend behind and below lower forks 14. The lower ends of these channels are rigidly connected by a cross member 19, behind which a horizontal roller 20 is journaled in the channels. As shown in Figs. and 10, this roller extends across the mast in engagement with the bottom of the front end of the upper section a short distance behind tongues 13. The ramps 21 are secured to the lower legs 8 of the upper section directly behind the roller.
Extending downward from the upper ends of the inclined braces 17 and the adjoining legs 5, as shown in Figs. 5 and 9, are a pair of track plates 22 which are in line with the vertical flanges of those legs. The plates are provided with forwardly opening recesses 23 having horizontal lower walls and upper walls that form tracks inclined upward and forward to the vertical flanges of the legs above. Fitting in these recesses are grooved wheels 24 journaled in the lower ends of triangular plates 25 that extend downward and forward from I the upper leg forks 1-1 of the upper mast section. These triangular plates are between track plates 22 and are provided with holes through which connecting pins 12 extend. With this construction, when the splice pins 12 and are removed, the upper section 2 of the reclining mast will remain supported by roller and by the engagement of wheels 24 with the track plates 22.
When the upper section is pulled forward and the ramps run up the roller, the wheels 24 run up the inclined tracks of the track plates 22 at the same time, but as those tracks are inclined more steeply than the ramps the front end of the upper section tilts up slightly and the rear end tilts downward. Consequently, the position of the center of gravity of the upper section does not change materially, so it does not require much effort to move the section. As the upper section is moved forward, its front end is raised by the roller and the tilting action until wheels 24 reach the lower edges of the vertical flanges of the upper legs 5 of the masts lower section. (See Fig. 6.) By that time the upper forks 11 and the adjoining front ends of the legs of the upper section are raised above the upper legs of the lower section.
Telescoping of the sections can be accomplished in any suitable manner, such as by a line attached to the upper section and to the cathead 27 (Fig. 3), or by anchoring the traveling block 28 (Fig. l) in the lower section and then operating the drawworks hoist (not shown) to reel in the line 29 on which the block is strung.
Extending from the lower ends of the ramps backward and up to the adjoining legs of the upper section are gently inclined tracks 31 which move across the roller as the upper section is pulled forward into the lower section. As long as the center of gravity of the upper section is behind the roller, the grooved wheels 24 are pressed up against the upper legs of the lower section which serve as guide rails, but when the center of gravity passes the roller the front end of the upper section will tend to tilt down. To prevent the front end of the upper section from dragging on the legs of the lower section, small rollers 32 are journaled in brackets 33 mounted beneath the horizontal flanges of the upper legs of the upper section. These rollers will engage the top of the upper legs of the lower section and run along them as the mast sections are telescoped, but the grooved wheels will remain close enough to those legs to prevent the front end of the upper section from shifting laterally out of correct position. When the upper section first starts to move ahead, rollers 32 move up inclined bars 34 fastened to the rear ends of upper tongues 10. Due to section is not raised above the lower section legs until ramp-like frame 35 at the crown rides up onto roller 20/ as shown in Fig. 3.
To untelescope or extend the mast the opposite ends of a sling line 36 are attached to anchor brackets {37 projected forward from the bottom of upper section? 2 between its legs, as shown in Figs. 8 and 10. This line extends back and down around vertical sheaves 38 fitstened to the front of cross member 19 between channels 18, and then forward around a pair of horizontal sheaves 39 also fastened to the cross member. By pulling forward on this sling, such as by means of the cathead 27, the upper section 2 will be pulled out of the lower section 3 until ramps 21 reach the roller, and then the upper section will move downward as well as backward to final position, in which the cooperating forks and tongues will be in positions to receive the splice pins 12 and 15. As soon as these pins are driven into place, the extended mast is ready to be raised.
It will be seen that this mast can be extended while reclining, so that good tight connections can be made between the two sections by workmen working close to V the ground. They do not have to climb an upright mast to connect or disconnect the sections, and the use of automatically operating latches is avoided. Consequently, the mast is rigid enough to make guy wires unnecessary. The end to end relation ofthe connected legs also adds to the strength and rigidity of the mast and saves material that would be required if the legs overlapped; Another feature of this invention is that the splice pin 12 and 15 at the joint between the two sections of the mast are permanently connected to the mast so that they will not become mislaid or lost and so that when they are driven'out of the forks they will not fly through the air and possibly injure someone. They also are held by mechanical supports in position to be driven into place. Accordingly, the head ends of pins 12 are between the opposite sides of the mast, and each is provided with trunnions 41 loosely mounted in longitudinal slots in one of the bifurcated ends of a channel-like arm 42, as shown in Figs. 8 and 9. The arm extends along the inner surface of the adjacent triangular plate 25 to a point near grooved wheel 24, where the arm is pivotally mounted between the ends of a pair of reinforcing bars 43 and 44 welded to the inner surface of the plate. A coil spring 45 fastened to bar 44 and the side of the arm, pulls the arm toward the plate. When the splice pin is driven back out of tongue 10 and fork 11, it swings the arm away frorn'the plate as shown in broken lines in Fig. 8. Pin 12 then generally will swing downward and be housed in the arm, as shown in Fig. 9, when the spring pulls the arm back toward plate 25. If the pin does not takethat position automatically, the workman can fold it into the arm. In any event, the splice pin cannot get away, but always is located where it can readily be inserted in the leg splice and then driven into place. When inserted in the splice, the pin is held there by spring 45 until driven into place, thereby eliminating the hazard of a man holding the pin while it is being driven.
The other splice pins 15 are mounted in the same way, except that because of space limitations it is preferred to locate their head ends outside of the mast. That outer end of each pin is provided with trunnions 51 loosely mounted in slots in one of the bifurcated ends of a channel-like arm 52, as shown in Figs. 5 and 8. The opposite end of the arm is pivotally mounted in a bracket 53 welded to the outside of the adjoining leg 4 of the mast. A coil spring 54 is stretched between the bracket and the side of the arm to pull the arm toward the leg. The arm holds the splice pin in driving position and after it has been driven out of the leg splice, and forms a convenient housing for the pin when it is not in use, as
' shown in dotted lines in Fig. 6.
7 According to the provisions of the patent statutes, we ihave explained the principle of our invention and have ililustrated and described what we now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended Clair-m, the invention may be practiced otherwise than as sfpecifically illustrated and described.
We claim:
El. An open front portable mast having a lower section anfd a'n upwardly tapered upper section and adapted to be swiung from upright position backward to reclining positidn, said lower section in its reclining position having a ipair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legsof the lower section, splicing means detachably connecting the front ends of the reclining upper section legs to the rear ends of the lower section legs, a cooperating ramp and ramp-engaging member substantially in engagement with each other below said sections and supported by their adjoining ends, the ramp and ramp-engaging member being positioned to raise the front ends of the upper section legs above the corresponding lower section legs when said reclining sections are disconnected at said splicing means and the upper section is moved forward, whereby to telescope the mast, and anti-friction members carried by the front end of the upper part of the reclining upper section and engageable with the upper and lower surfaces of said upper legs of the reclining lower section as the mast is telescoped, whereby to hold the reclining upper section in general alignment with the reclining lower section so that the upper section can be supported solely by the lower section during telescoping.
2. An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legs of the lower section, splicing means detachably connecting the front ends of the reclining upper section legs to the rear ends of the lower section legs, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, and short ramps secured to the bottom of the reclining upper section and extending downward and backward therefrom behind said support substantially in engagement therewith, whereby when said reclining sections are disconnected at said splicing means and the upper section is moved forward said transverse support and ramps will raise the front ends of the upper section legs above the corresponding lower section legs to permit the upper section to be telescoped into the lower section.
3. An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining posi- 6 tion, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs extending backward beyond the upper legs, said upper section in its reclining position having a pair of lower legs in end to end relation with the lower legs of the lower section and having a pair of upper legs extending forward beyond its lower legs and in end to end relation with the upper legs of the lower section, splicing means detachably connecting the front ends of the upper section legs to the rear ends of the lower section legs, whereby the front end of the upper section normally overlaps the rear end.of the lower section, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, and short ramps secured to the bottom of the reclining upper section and extending downward and backward behind said support substantially in engagement therewith, whereby when said reclining sections are disconnected at said splicing means and the upper section is moved forward said transverse support and ramps will raise the front ends of the upper section legs above the corresponding lower section legs.
4. An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legs of the lower section, splicing means detachably connecting the front ends of the upper section legs to the rear ends of the lower section legs, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, short ramps secured to the bottom of the reclining upper section and extending downward and backward behind said support substantially in engagement therewith, whereby when said reclining sections are disconnected at said splicing means and the upper section is moved forward said transverse support and ramps will raise the front ends of the upper section legs above the corresponding lower section legs and means then holding the front ends of the upper legs of the upper section a predetermined distance above the lower section so that the upper section can be telescoped into the lower section.
5. An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legs of the lower section, splicing means detachably conmeeting the front ends of the upper section legs to the rear ends of the lower section legs, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, short ramps secured to the botttom of the reclining upper section and extending downward and backward behind said support substantially in engagement therewith, whereby when said reclining sections are disconnected at said splicing means and the upper section is moved forward said transverse support and ramps will raise the front ends of the upper section legs above the corresponding lower section legs, and means carried by the upper section for supporting the front ends of its upper legs above the lower section after the center of gravity of the upper section has moved forward past said transverse support.
6. An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs extending backward beyond the upper legs, said upper sec- 7 tion in its reclining position having a pair of lower legs in end to end relation with the lower legs of the lower section and having a pair of upper legs extending forward beyond its lower legs and in end to end relation with the upper legs of the lower section, splicing means detachably connecting the front ends of the upper section legs to the rear ends of the lower section legs, whereby the front end of the upper section normally overlaps the rear end of the lower section, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, short ramps secured to the bottom of the reclining upper section and extending downward and backward behind said support substantially in engagement therewith, and wheels carried by the upper section of the mast at such distance below the upper legs of the reclining lower section that when said sections are disconnected at said splicing means and the upper section is moved forward so that said transverse support and ramps raise the front ends of the upper section legs above the corresponding lower section legs said wheels will be moved up against the upper legs of the lower section and will roll forward along them as the upper section is telescoped into the lower section.
' 7, An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legs of the lower section, splicing means detachably connecting the front ends of the upper section legs to the rear ends of the lower section legs, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, short ramps securedto the bottom of the reclining upper section and extending downward and backward behind said support substantially in engagement therewith, whereby when said reclining sections are disconnected at said splicing means and the upper section is moved forward said transverse support and ramps will raise the front ends of the upper section legs above the corresponding lower section legs so that the upper section can be telescoped into the lower section, means carried by the upper section of the mast for then engaging the lower surface of the upper legs of said lower section to limit upward movement of the front ends of the upper section legs, and means carried by the upper section for supporting the front ends of its upper legs above the lower section after the center of gravity of the upper section moves forward past said transverse support.
8. An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legs of the lower section, splicing means detachably connecting the front ends of the reclining upper section legs to the rear ends of the lower section legs, a transverse support carried by the rear end of the reclining lower section substantially in engagement with the bottom of the upper section, short ramps secured to the bottom of the reclining upper section and extending downward and backward behind said support substantially in engagement therewith, wheels carried by the upper section of the mast below the upper splicing means, and tracks inclined from the upper legs of the lower section downward and backward over the wheels substantially in engagement therewith, whereby when said reclining sections are disconnected at said splicing means and the upper section is moved forward said transverse support and ramps will raise the upper section legs above the corresponding lower section legs as the wheels run up said tracks, so that the upper section can be telescoped into the lower section while the wheels run forward along the bottoms of the upper legs of the lower section.
9. An open front portable mast in accordance with 0 claim 8, wherein said tracks are inclined more steeply than said ramps.
10. An open front portable mast in accordance with claim 8, wherein said tracks have recesses at their lower ends receiving said wheels to support them when the mast is extended but said splicing means are disconnected.
11. An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to reclining position, said lower section in its reclining position having a pair of parallel upper legs, and a pair of lower legs extending backward beyond the upper legs, said parallel legs having downwardly extending flanges, said upper section in its reclining position having a pair of lower legs in end to end relation with the lower legs of the lower section and having a pair of upper legs extending forward beyond its lower legs and in end to end relation with the upper legs of the lower section, splicing means detachably connecting the front ends of the upper section legs to the rear ends of the lower section legs, whereby the front end of the upper section normally overlaps the rear end of the lower section, a horizontal roller carried b the rear end of the reclining lower section transverseg thereof substantially in engagement with the bottom f the upper section, short ramps secured to the bottomi-of the reclining upper section and extending downward agld backward behind the roller substantially in engagement therewith, grooved wheels disposed below said leg flanges, and means supporting the wheels secured to the inside of the upper section of the mast, whereby when said rd;- clining sections are disconnected at said splicing means and the upper section is moved forward the roller anirl ramps will raise the upper section legs above the cor;- responding lower section legs and said wheels will engage the bottoms of said leg flanges and roll forward along them as the mast is telescoped. i
12. An open front portable mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position backward to recliniing position, said lower section in its reclining position having a pair of parallel upper legs and a pair of lower legs, said upper section having legs in end to end relation with the legs of the lower section, the adjacent ends of the legs having interfitting portions provided with aligned transverse holes, splice pins in said holes detachably connecting the front ends of the reclining upper section legs to the rear ends of the lower section legs, an arm pivotally connected at one end to each pin, means pivotally connecting the opposite end of the arm to the mast, a cooperating ramp and rampengaging member substantially in engagement with each other below said sections and supported. by their adjoining ends, the ramp and ramp-engaging member being positioned to raise the front ends of the upper section legs above the corresponding lower, section legs when said reclining sections are disconnected at said splicing means and the upper section is moved forward, whereby to telescope the mast.
13. An open front portable mast in accordance with claim 12, in which each pin-supporting arm is channellike and has its open side facing the mast and adapted to receive the pin after it has been removed from said holes, and a spring urging said first-mentioned end of the arm toward the mast,
14. An open front portable oil well mast having a lower section and an upwardly tapered upper section and adapted to be swung from upright position down to reclining position, said lower section in its reclining position having a pair of upper legs and a pair of lower legs, the pair of legs at the open front of the lower section being substantially parallel, said upper section having legs in end to end relation with the legs of the lower section, splicing means detachably connecting the upper section legs to the lower section legs, means for moving the reclining upper section toward the lower section after the reclining sections are disconnected at said splicing means, and means for guiding the reclining upper section vertically toward the open front of the reclining lower section as the upper section is first moved toward the lower section, whereby to move the legs of the two sections out of end to end relation to permit the upper section to telescope into the lower section, the reclining mast being provided with vertically spaced track surfaces extending lengthwise thereof and with anti-friction members above and below said surfaces and engageable with them as the mast is telescoped, whereby to hold the reclining upper section in general alignment with the reclining lower section so 10 that the upper section can be supported solely by the lower section during telescoping.
References Cited in the file of this patent UNITED STATES PATENTS 2,042,353 Morehouse May 26, 1936 2,076,811 Ehlers Apr. 13, 1937 2,210,407 Henry Aug. 6, 1940 2,331,558 McEwen et al. Oct. 12, 1943 2,465,813 Moore Mar. 29, 1949 2,577,642 Woolslayer et a1. Dec. 4, 1951
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US382342A US2804948A (en) | 1953-09-25 | 1953-09-25 | Telescoping portable mast |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US382342A US2804948A (en) | 1953-09-25 | 1953-09-25 | Telescoping portable mast |
Publications (1)
Publication Number | Publication Date |
---|---|
US2804948A true US2804948A (en) | 1957-09-03 |
Family
ID=23508528
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US382342A Expired - Lifetime US2804948A (en) | 1953-09-25 | 1953-09-25 | Telescoping portable mast |
Country Status (1)
Country | Link |
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US (1) | US2804948A (en) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4021978A (en) * | 1973-10-17 | 1977-05-10 | Cabot Corporation | Mast assembly |
US4393630A (en) * | 1981-03-12 | 1983-07-19 | Crane Carrier Corporation | Actuation means for the racking platform of a mast |
US4598509A (en) * | 1985-06-24 | 1986-07-08 | Lee C. Moore Corporation | Method and apparatus for raising and lowering a telescoping mast |
EP0312286A2 (en) * | 1987-10-13 | 1989-04-19 | Branham Industries, Inc. | Folded/telescoped drill rig mast for limited space platform |
US20090218139A1 (en) * | 2008-02-29 | 2009-09-03 | Robert Benjamin Donnally | Drilling rigs and erection methods |
US20090218144A1 (en) * | 2008-02-29 | 2009-09-03 | Robert Benjamin Donnally | Drilling rig masts and methods of assembly and erecting masts |
US8813436B2 (en) | 2008-02-29 | 2014-08-26 | National Oilwell Varco, L.P. | Pinned structural connection using a pin and plug arrangement |
US9091125B2 (en) | 2012-01-16 | 2015-07-28 | National Oilwell Varco, L.P. | Collapsible substructure for a mobile drilling rig |
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Publication number | Priority date | Publication date | Assignee | Title |
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US2042353A (en) * | 1934-11-05 | 1936-05-26 | Morehouse Terry Bryan | Connection for structural members |
US2076811A (en) * | 1935-01-16 | 1937-04-13 | Ehlers Edward | Structural joint for angle bars |
US2210407A (en) * | 1938-09-02 | 1940-08-06 | Lee C Moore & Company Inc | Portable derrick |
US2331558A (en) * | 1941-02-14 | 1943-10-12 | Int Stacey Corp | Portable derrick |
US2465813A (en) * | 1946-02-19 | 1949-03-29 | Dewey R Moore | Portable derrick |
US2577642A (en) * | 1948-09-25 | 1951-12-04 | Moore Corp Lee C | Oil well derrick |
-
1953
- 1953-09-25 US US382342A patent/US2804948A/en not_active Expired - Lifetime
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2042353A (en) * | 1934-11-05 | 1936-05-26 | Morehouse Terry Bryan | Connection for structural members |
US2076811A (en) * | 1935-01-16 | 1937-04-13 | Ehlers Edward | Structural joint for angle bars |
US2210407A (en) * | 1938-09-02 | 1940-08-06 | Lee C Moore & Company Inc | Portable derrick |
US2331558A (en) * | 1941-02-14 | 1943-10-12 | Int Stacey Corp | Portable derrick |
US2465813A (en) * | 1946-02-19 | 1949-03-29 | Dewey R Moore | Portable derrick |
US2577642A (en) * | 1948-09-25 | 1951-12-04 | Moore Corp Lee C | Oil well derrick |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4021978A (en) * | 1973-10-17 | 1977-05-10 | Cabot Corporation | Mast assembly |
US4393630A (en) * | 1981-03-12 | 1983-07-19 | Crane Carrier Corporation | Actuation means for the racking platform of a mast |
US4598509A (en) * | 1985-06-24 | 1986-07-08 | Lee C. Moore Corporation | Method and apparatus for raising and lowering a telescoping mast |
EP0312286A2 (en) * | 1987-10-13 | 1989-04-19 | Branham Industries, Inc. | Folded/telescoped drill rig mast for limited space platform |
US4837992A (en) * | 1987-10-13 | 1989-06-13 | Branham Industries, Inc. | Folded/telescoped drill rig mast for limited space platform |
EP0312286A3 (en) * | 1987-10-13 | 1990-10-31 | Branham Industries, Inc. | Folded/telescoped drill rig mast for limited space platform |
US20090218139A1 (en) * | 2008-02-29 | 2009-09-03 | Robert Benjamin Donnally | Drilling rigs and erection methods |
US20090218144A1 (en) * | 2008-02-29 | 2009-09-03 | Robert Benjamin Donnally | Drilling rig masts and methods of assembly and erecting masts |
US8468753B2 (en) | 2008-02-29 | 2013-06-25 | National Oilwell Varco L.P. | Drilling rigs and erection methods |
US8549815B2 (en) * | 2008-02-29 | 2013-10-08 | National Oilwell Varco L.P. | Drilling rig masts and methods of assembly and erecting masts |
US8813436B2 (en) | 2008-02-29 | 2014-08-26 | National Oilwell Varco, L.P. | Pinned structural connection using a pin and plug arrangement |
US9091125B2 (en) | 2012-01-16 | 2015-07-28 | National Oilwell Varco, L.P. | Collapsible substructure for a mobile drilling rig |
US9556676B2 (en) | 2012-01-16 | 2017-01-31 | National Oilwell Varco, L.P. | Collapsible substructure for a mobile drilling rig |
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