US2365798A - Device for loading explosives in wells - Google Patents

Description

Dec. 26, 1944. w. P. BLAIR ET A1. 2,365,798

DEVICE FOR LOADING EXPLOSIVES IN WELLS Filed Dec. 2o, 1940 2 sheets-smet 1 Dec. 26, 1944. W p. B| A|R ET AL 2,365,798

DEVICE FOR LOADING EXPLOSIVES IN WELLS Filed Dec. 2O 1940 2 Sheets-Sheet 2 /M w, M Zu r n ffm m Si I\ ./...1 V N m5. f m W5 Ww lf. .m A w w ff. www, au, A, M y, W W @y @d i a w 7 0 f6 M/ i @Hm w w.. y n0,/ T L, c --1 l :y l .n.mwmmm @atented ec. 26, i944 rares DEVICE FOR LADDIG EHLSIVES IN WELLS Oklahoma Application December 20, 1940, Serial No. 370,974

(Cl. ll66 19) 14 Claims.

This invention relates to devices for loading explosives into wells, such as oil, gas and water wells, and particularly to such devices i the type commonly known to the art as dump shells.

In employing dump shells for loading explosives into wells, the explosive, which is ordinarily a gelatinized form of nitroglycerine, is placed in a. suitable container, provided with a bail to .which the lowering line is attached and with a bottom dump valve or releasable plug. rIhis container is lowered into the well, and when. it reaches the bottom at the point where the explosive is to be placed, the dump valve is opened Iby suitable release mechanism ordinarily operated from the lowering line. The gelatinous mass of explosive is then discharged from the container into the well. Generally, a plurality of charges of explosive are thus deposited in the well by means of the same container until the space within which the explosion is to occur is closely packed with the explosive material.

It is particularly desirable in employing dump shells in the manner described that complete dumping of each charge of explosive from the shell be assured so thatnone of the explosive will be carried back to the surface with the container when it is withdrawn from the well for recharging. It is also particularly desirable that as little solid, non-explosive matter as possible be deposited in the well during the loading operation, and that metal-to-metal contacts which may produce sparks be avoided to reduce the hazard of premature explosions.

The present invention is directed to dump shells of this general character, and more specifically to improvements in the valve or plug, and the mechanism for releasing it. In the present invention I provide a valve or plug which is separated from the casing when released. This eliminates-any possibility `that the valve will be unintentionally closed after it has .been opened, and thus assures a complete discharge of the explosive from the shell.

In accordance with this invention, the desirable objects and advantages above-enumerated, as well as others, are attained Iby means of an improved form of dump shell, several modications of which are illustrated in the acompanying drawings and are described in detail in the following specication. In the drawings:

Fig. l is a longitudinal, partly-sectional view of a dump shell in accordance with one modification of this invention;

Figs. 2, 3 and 4 are views similar to Fig. i illustrating diierent positions of the release mechanism of the shell during the course of the dumping operation;

Fig. 5 is a side elevationof the upper end of the shell, at right angles to Fig. l;

Fig. 6 is a longitudinal elevation of a durnp shell in accordance withanother modification of this invention, parts being shown in section;

Fig. 7 is a horizontal, sectional view on line 'll of Fig. 6;

Figs. 8 and 9 are details of one form of closure adapted for use with the modification of Fig. 6;

Fig. l0 is a vertical, sectional view of the lower end of the shell of Fig. 6, showing another form of valve; and

Fig. 11 is a plan view of the valve shown in. Fig. 10.

Referring to Figs. l to 5 of the drawings, the device consists of an elongated hollow tubular casing 2li constructed preferably of light sheet metal, such as tin plate or the like, which is open at both end. Secured to the upper end of casing 2D is an elongated U-shaped bail 2l, having the lower ends of its arms securely attached at opposite sides to the upper end of casing 20. A spacer bar 22 extends transversely between the arms of bail 2l at a point intermediate the open upper end of casingl 2l] and the bow portion of bail 2l. Spacer bar 22 and the lbow portion of bail 2l, respectively, are provided with registering openings 23 and 24 in alignment with the longitudinal axis of casing 20. A tubular sleeve v25 extends between spacer -bar 22 and the bow portion of Ibail 2l and encloses `both the openings 23 and 2d. A tubular stem 26 extends from above bail 2| through openings 23 and 24 and sleeve 25 to below spacer bar 22. Stern 26 is adapted to slide longitudinally through the sleeve 25 and the openings 23 and 2li. A ring 2l is attached to the upper end of stem 26 for attachment of a lowering line 28. Stem 26 is provided in an intermediate lportion thereof with a transverse slot 29. A dog 3U is positioned in the slot and eccentrically journalled in the sides of stem 26. A key slot 3| extends through stern 26 at a point above slot 29 and is adapted to receive a wedgeshaped key 32. A bushing 33 is threadeclly inserted into the lower end oi .stem 26 and is provided with an axial opening 34 through which the upper end of a rod 35 extends into the bore of stem 26. The upper end of rod 35 is provided with a cap 36 which cooperates with the inner end of bushing 33 to prevent downward withdrawal of the end of -rod 35 from the bore of stem 26. The described arrangement of rod 35 in stem 26 permits relative telescoping movement between these parts, as shown 'by the extended dotted outlines of stern 25 in Fig. l. Rod 35 extends axially of from the lower end of rod 35.

provided with an upper shank portion 39 which is adapted to be inserted into the lower end of casing 20 to form a closure therefor. Shank 39 terminates at an annular shoulder 40 which engages the lower end of casing 20 and thereby limits the extent of insertion of the plug into the casing. The lower portion of plug 38 below shoulder 40 forms an extended tip of generally conical shape, although the shape of this tip is largely immaterial. It may be round or 'at or of any other suitable configuration. The shank portion 39 is provided in each its half-sections with complementary grooves 4| which terminate in the interior of the plug in a conical recess 42.

When the half-sections of plug 38 are closed about the lower end of rod 35, tip 31 will be received in recess 42 and the adjacent portion of rod 35 will be received in groove 4|. When the shank of plug 38 is inserted in the lower end of casing by drawing rod 35 upwardly through the casing, the plug will be held in place in the end of the casing by the wedging action of tip 31 against the adjacent faces of recess 42 and by the cooperation of shoulder4|l with the lower edge of casing 20. Ears 43 (see Fig. 5) may be attached at opposite sides of the upper portion of bail 2| for attachment of the usual well rig hoisting line whenever it is desired to lift the shell from the well rig floor or from some other place before attachment of lowering line 28, Iin order to avoid placing an undesirable bending strain on stern 26. A chain 44 or other flexible tie means connects key 32 to one of the ears 43 to prevent loss of the key when not used for locking stem 26 in its fully extended position.

The operation of the above-described dump shell is as follows: The half-sections of closure plug 38 are placed about the lower end of rod 35 and tip 31 and shank 39 is inserted in the lower end of casing 26, stem 26 being drawn upwardly to the fully elevated position illustrated particularly in Figs. 1 and 2. Key 32 is inserted in slot 3| and the entire device suspended vertically from lowering line 28. When the shell is thus suspended from the lowering line, the weight of the shell on the shoulder 40 will holdthe plug in place in the end of the casing, and the key 32 is not necessary for any purpose except as a precautionary measure in the event some unexpected upward movement is applied to the shell. It is useful, however, to keep the plug 38 in place and the parts in their assembled relationship when the shell is not in suspended position. Casing 2U is now lled with the explosive material, which as stated above, is usually of a gelatinous or jelly-like composition which will ordinarily slide from the lower end of the casing when the plug is removed. This sliding vof the explosive from the container is usually aided by coating the interior of the casing with a suitable lubricant. It will be seen that the weight of the shell and explosive will be supported on the tapered surface of tip 31 which cooperates with the adjacent tapered surfaces of recess 42 to cause an expanding movement of the half-sections of plug 38 into tight engagement with the walls of casing 20. Thus, so long as the weight of the shell and contents is carried by stem 26 and rod 35 closure plug 38 will be held in place in the end of" the shell casing.

Key 32 is now withdrawn from slot 3| and the loaded shell is lowered into the well. When the tip of closure 38 strikes the bottom of the well, the downward progress of casing 29, bail 2| and rod 35 are arrested but stem 26 is free to continue its downward movement, by telescoping over rod 35, until its downward movement is arrested by contact of ring 21 with the `bow portion of bail 2|. The resultant position of stem 26 is shown by the dotted outlines in Fig. 1, and more completely in Fig. 3. This continued downward movement of stem 26 brings slot 29 and dog 30 out of sleeve 25 and below spacer plate 22, whereupon dog 39, being normally unbalanced by its eccentric journalling in slot 29, rotates to the position shown in Figs. 3 and 4. An upward pull is then applied to line 28 which pulls stem26 upwardly toward its normal position until dog 38 comes in contact with the under side of spacer plate 22 (Fig. 4), whereupon the upward pull on line 28 becomes applied to casing 20. At the same time, contact of dog 30 with spacer plate 22 prevents return of bushing 33 into contact with cap 36 on the upper end of rod 35 with the result that some relative movement between the upper end of rod -35 and bushing 36 can occur after dog 30 contacts spacer plate 22 upon continued upward movement of line 28. The extent of this relative movement is suilicient to allow casing 2D to be pulled off of shank 39 of closure 38 which is held the weight of the explosive bearing on the top of the plug. As soon as plug 38 is freed from confinement within the end of the casing, the half-sections of the plug separate and are thrust away from tip 31 by the weight of the explosive and the wedging action of tip 31 against the sides of recess 42. The explosive material is then discharged from the end of the casing, sliding out of its own weight, and deposits in the well. The entire shell with the exception of closure plug 38, is then withdrawn from the well. A. new closure plug is then inserted in the end of the casing in the manner described and the shell loading and dumping operations repeated until a suicient charge of explosive has been discharged into the well.

By employment of a dump shell of the abovedescribed construction, having a fully releasable plug, positive and full opening of the lower end of the shell is assured, so ythat complete discharge of the contained explosive will take place without danger that any explosive will remain in the shell when it is withdrawn from the well. By leaving only the closure plug in the well, a minimum amount of non-explosive solid matter will thus remain in the well to interfere with subsequent clean-out operations.

Since closure plug 38 serves only as a temporary closure and is discarded with each use, it may be made of any cheap and convenient material, metallic or non-metallic, which is, however, non-sparking in character, Plug 38 may be made of non-sparking metals such as aluminum or copper, or of various non-sparking metal alloys. It may also be constructed of many non-metallic materials such as glass, wood, resinous plastics, compressed' paper or the like. It is preferable, however, to employ a material which may be easily shattered by the explosion or which may be easily ground up by the tools employed in cleaning out the well following detonation of the explosive.

Figs. 6 to 9 illustrate another modification of a dump shell in accordance with this invention having a slightly modied form of closure plug and release mechanism therefor. In this modification the central rod 35 of Fig. l is replaced by a pair of rods 58-50 which are slidable externally on opposite sides of casing 20 and are attached at their upper ends to the opposite ends of a transverse yoke Yoke 5I is slidable externally of stem 26 betweenf'spacer plate 22 and a stop member 52 attached to the lower end of stem 26. The lower ends of rods 50-50 are turned inwardly toward the axis of the shell to form lugs 54-54 which engage in complementary recesses 53 formed in the outer surfaces of the half-sections of plug 38a and on opposite sides thereof below shoulder 40. An annular ring 55 encircles the lower end of casing20 and is provided `at opposite sides with openings 56-56 through which the lower ends of rod Sil-50 are slidably guided to prevent spreading of the ends of rods 50-50 under the weight of the explosive on 'top of the closure plug.

This modification is operated by exactly the same mechanical movements of stem 26 and dog 3!) as the previously described modification, to eiect release of closure plug 38a and to discharge the explosive.

Figs. and l1 illustrate details of another variation of the modification illustrated in Fig. 8,

able plug mounted in the lower end of the casing and serving as a closure therefor, plug retaining means comprising a lower member extending longitudinally of the casing, engaging the plug to retain it in position and being separable therefrom, and an upper retaining member connected to the lower retaining member, the retaining members being capable of limited longitudinal contractura] and extending movement, the upper end of the' upper retaining memberl beingadapted to be secured to a lowering line, the plug 'retaining means being suspended in extended relation by the lowering line, /and means operative upon predetermined longitudinal contractural movement between the upper and lower retaining members to lock the upper retaining member against movement with respect to the casing whereby upward movement of the upper retaining member and the casing causes the lower retaining member and the plug to move relatively to the casing to release the plug.

2. In a device of the character described, a casing having an outlet opening in the bottom, a separable plug received in the opening, plug retaining means extending through the casing and adapted to` be secured to a lowering line whereby upward pull is placed on the plug retaining means to hold the plug in position during lowering into a well, the plug retaining means comprising a lower member engaging the plug and an upper member connected to the lower member, the upper and lower retaining members being relatively movable to permit limiting longitudinal contractural and extending movement of the retaining means, and means carried by the upper retaining member and engageable with a part of the casing when the retaining means is contracted to lock the upper retaining member against relative movement with respect to the casing.

3. In a device of the character described, a cylindrical casing having an open lower end, a releasable plug closing the lower end of the casing, the plug having a shoulder engaging the lower end of the casing, plug retaining means comprising a lower member extending longitudinally of the casing and engaging the plug and an upper retaining member connected to the lower retaining member to permit relative longitudinal movement of said members with respect to each other and with respect to the casing, the retaining means being capable of longitudinal limited contractural and extending movement, the upper end of the upper retaining member being adapted to be secured to a lowering line, and a dog carried by the upper retaining member engageable with a part of the casing when the retaining member is contracted to lock the upper retaining member to the casing.

4. A dump shell for vlowering explosives into a well comprising a casing having a discharge opening in the bottom thereof, a fully separable plug closing said opening, and means for retaining the plug in position, said means comprising a lower retaining member engaging the plug and an upper retaining member extending above the top of the shell` for attachment to a lowering line, the

retaining members being connected to each other to permit relative movement and being movable with respectto the casing, the retaining means being capable of limiting longitudinal contractural and extending movement, and means for locking the upper retaining member to the casing when the retaining means is contracted to permit relative downward movement of the lower retaining member and release of the plug.

5. A device of the character described comprising a substantially cylindrical casing, a fully releasable plug mounted in the lower end of the casing, plug retaining means extending longitudinally of the casing, the .plug retaining means comprising an upper member and a lower member connected to each other to permit relative movement to'elect limiting longitudinal contractura] and extending movement, a sleeve carried on the casing, the upper retaining member being mounted in the sleeve, the upper end of the upper retaining member being adapted to be secured to a lowering line, and means carried by the upper retaining member to engage a portion of the casing when the retaining means is contracted to lock the upper retaining member against movement with respect to the casing.

6. In a device of the character described, a substantially cylindrical casing, a fully releasable plug mounted in the lower end of the casing, plug retaining means comprising a lower member extending longitudinally of the casing and engaging the plug and an upper member mounted in the casing, the upper member being loosely connected to the lower member, the plug retaining means being capable of limiting longitudinal contractural and extending movement, the upper retaining member being adapted to be secured to a lowering line, the plug retaining means being suspended in expanded relation by the lowering line, and means carried by/the upper retaining member and adapted to engage a portion of the casing when the retaining means is contracted to lock the casingrand upper retaining member against relative movement.

'7. In a device of the character described a substantially cylindrical casing, a fully releasable plug mounted in the lower end of the casing, plug retaining means comprising a lower member extending longitudinally of the casing and engaging the plug and an upper member mounted in the casing, the upper member being connected to the lower member to permit limited relative movement, the retaining means being capable of limiting longitudinal contractural and extending movement, the upper member being adapted to be secured to a lowering line, the plug retaining means being suspended in extended relation by the lowering line, and a dog carried by the upper member and adapted to engage a portion of the casing when the retaining means is contracted to lock the upper member and casing against relative longitudinal movement.

8. In a device of the character described, a. substantially cylindrical casing, a fully releasable plug mounted in the lower end of the casing, plug retaining means comprising a lower member extending longitudinally of the casing and an upper member connected to the lower member to permit limited relative longitudinal movement of said members, the plug retaining means being capable of limiting longitudinal contractural and extending movement, a sleeve carried on the upper end of the casing, a spacer bar arranged adjacent the lower end of the sleeve, the upper end of the upper retaining member being adapted to be secured to a lowering line, the plug retaining means being suspended in extended relation by the lowering line, and means carried by the upper member and engaging the spacer bar when the retaining means is contracted'to lock the upper retaining member and casing againstl relative movement.

9. In a device of the character described, a substantially cylindrical casing, a fully releasable plug mounted in the lower end of the casing, the plug being for-med in two sections, plug retaining means comprising a lower member extending longitudinally of the casing and engaging the sections of the plug, and an upper retaining member connected to the lower retaining member to permit limited longitudinal movement oi said members, the .plug retaining means being capable of movement with respect to the casing, the upper retaining member being adapted to be secured to a lowering line, the plug retaining means being suspended in extended relation by the lowering line, and means carried by the upper member and engaging a portion of the casing when the retaining means is contracted to lock the upper member against relative movement with respect to the casing.

l0. In a device of the character described, a substantially cylindrical casing, a fullyreleasable plug mounted in the lower end of the casing, said plug retaining means comprising a rod extending axially of the casing7 and a second member telescopically connected thereto to permit limiting relative longitudinal movement of said members with respect to each other and with respect to the casing, the second member being adapted to be Secured to a lowering line, the plug retaining means being 'suspended in extended relation by the lowering line, and means carried by the second member and engaging a portion or the casing when the retaining means is contracted to lock the second member against relative movement with respect to the casing.

ll. A device of the character described comprising a substantially cylindrical casing, a plug niouni id in the lower end of the casing, the plug comp a pair of sections having registering grooves and recesses on their adjacent faces, a plug retaining member mounted in the casing, said plug retaining member comprising a rod arranged axially of the casing and having an enlargement on its lower end, the enlargement being received in the recess-es of the plug with the lower end of the rod in the grooves to retain the plug in position, and a second member slidably mounted on the casing, said members being connected to each other to permit limiting longitudinal movement with respect to each other and with respect to the casing, the second member being adapted to be secured to a lowering line, the plug retaining means being suspended in extended relation by the lowering line, and means carried by the second member and adapted to engage a portion of the casing when the retaining means is contracted to lock the second member against relative movement with respect to the casing.

l2. In a device of the character described, a

f' substantially cylindrical casing, a plug removably mounted in the lower end of the casing,

plug retaining means mounted on the casing, said' plug retaining means comprising a pair of rods arranged exteriorly of the casing having their lower ends shaped to engage the plug to hold it in place, and a second member slidably mounted on the casing, s aid members being connected to each other to permit limited. longitudinal movement with respect to each other and with respect to the casing, the second member being adapted to be secured to a lowering line, the plug retaining means being suspended in extended relation by the lowering line, and means being carried by the second member and adapted to engage the casing when the retaining means is contracted to lock the second member against relative movement with respect to the casing.

13. In a device of thecharacter described, a substantially cylindrical casing, a plug removably mounted in the lower end of the casing, plug retaining means mounted on the casing, said plug retaining means comprising a pair of rods arranged exteriorly of the casing having their lower ends shaped to engage the plug to hold it in place, a sleeve mounted on the upper end of the casing, and a second member slidably mounted in the sleeve, said members being connected to each other to permit limited longitudinal relative movement of said members with respect to each other and with respect to the casing, the second member being adapted to be secured to a lowering line, the plug retaining means being suspended in extended relation by the lowering line, and means carried by the second member and engaging a portion of the casing when the retainingA means is contracted to lock said second member against relative movement with respect to the casing.

14. In a device of the character described, a substantially cylindrical casing, a plug removably mounted in the lower end of the casing, plug retaining means mounted on the casing, said plug retaining means comprising a pair of rods arranged exteriorly of the casing having their lower ends shaped to engage the plug to hold it in place, a sleeve mounted on the upper end of the casing, a spacer bar arranged adiacent the lower end of the sleeve, and a second member slidably mounted in the sleeve, said members being connected to each other to permit relative longitudinal movement ci said members with respect to each other and with respect to the casing, and a key carried by the second member and adapted to engage the spacer bar when the retaining means is contracted tc lock the second member against; relative movement with respect to the casing.

WALLACE P. BLAIR. WILLY A. SCHILLINGER.

Images