US3643285A

US3643285A - Sludge scoop for oil tankers

Info

Publication number: US3643285A
Application number: US857154A
Authority: US
Inventors: Henry J Modrey
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-09-11
Filing date: 1969-09-11
Publication date: 1972-02-22
Anticipated expiration: 1989-02-22

Abstract

This invention is directed to apparatus for removing sludge from the bottom of the tanks of an oil tanker and includes a hoisting winch at the top of the tank with its cable extending down into the tank and attached to a sludge scoop initially remotely located at the bottom of the tank. An adjustably positioned snatch block is used to control the lead of the cable and to establish the desired path of travel of the sludge scoop.

Description

United States Patent Modrey Feb. 22, 1972 [54] SLUDGE SCOOP FOR OIL TANKERS [72] Inventor: Henry .1. Modrey, Eagle Drive, Stamford,

Conn. 06903 [22] Filed: Sept. 11, 1969 [21] Appl.No.: 857,154

[52] U.S.Cl ..15/246.5, 15/93, 37/135,

172/265, 214/15 C [51] Int. Cl ..B63b 57/00 [58] Field of Search 1 5/104. 1 6, 104.3, 236, 246.5,

[56] References Cited UNITED STATES PATENTS 493,421 3/1893 Butler ..37/136 2,147,663 2/1939 Miller ..37/135 X 2,147,634 2/1939 Campbell ..37/135 X FOREIGN PATENTS OR APPLICATIONS 869,885 6/1961 Great Britain ..37/135 Primary Examiner-Edward L. Roberts AttorneyI-Iane & Baxley [5 7] ABSTRACT This invention is directed to apparatus for removing sludge from the bottom of the tanks of an oil tanker and includes a hoisting winch at the top of the tank with its cable extending down into the tank and attached to a sludge scoop initially remotely located at the bottom of the tank. An adjustably positioned snatch block is used to control the lead of the cable and to establish the desired path of travel of the sludge scoop.

5 Claims, 15 Drawing Figures BPEQBWZSS flfi E FEB 2 7% SHEET 0F 3 INVENTOR.

HENRY J. MODREY Ham M EMZ A-r ra/e/va rs SLUDGE SCOOP FOR OIL TANKERS THE INVENTION This invention relates generally to new and useful improvements in devices for removing sludge from the bottoms of tanks and particularly seeks to provide a novel cable-operated scoop for removing sludge that accumulates between the fore and aft stringers or ribs at the bottoms of oil tanker holds.

For the purposes of this description it is believed sufficient to state that a typical tank hold is defined by the hull and bottom plating, the deck plating, the longitudinal bulkhead, and a pair of transverse bulkheads. The bottom of the hold is stiffened by a plurality of spaced generally parallel longitudinal channels or ribs. Surging of the tank contents in a seaway is minimized by suitably positioned transverse and/or longitudinal baffles. Access to each hold is generally gained through small circular holes in the deck that are normally closed by cover plates removably bolted thereover.

Crude oil carried within the hold will deposit a sludge on and between the longitudinal channels or ribs that must be removed periodically when the hold is empty. Normally, efforts are made to establish and maintain a cleaning cycle such that no more than a few inches of sludge builds up between cleanings. The sludge between the stringers is difficult and messy to remove, and washing alone is generally insufficient for the removal of sludge deposits. Heretofore, its removal has been effected manually by shoveling the sludge into a relatively small capacity bucket and hoisting it out through the deck holes.

However, through the use of this invention sludge removal is substantially mechanized and the operation may be effected in a much shorter time and with little or no shovel work, except for possible trimming.

Therefore, an object of this invention is to provide a cableoperated scoop for the removal of sludge from the bottoms of oil tankers holds.

Another object of this invention is to provide a removable or foldable holddown handle to hold the mouth of the scoop toward contact with the bottom plates of the hold.

Another object of this invention is to provide a scoop of the character stated that includes a permanent magnet releasably secured to the bottom of the scoop adjacent the mouth thereof to draw the mouth portion downwardly toward contact with the bottom plates of the hold.

Another object of this invention is to provide a scoop of the character stated in which the operating cable therefor is led downwardly from a deck opening and reeved through a quick opening snatch block adjustably positioned between a selected pair of channels or ribs and then to the bail or bridle of the scoop to which it is releasably connected as by a snaphook.

Another object of this invention is to provide a scoop of the character stated in which the snatch block is adjustably mounted on a thwartship bar that is releasably and adjustably clamped to a selected channel or rib.

A further object of this invention is to provide a scoop of the character stated in which the scraper edge at the mouth thereof is angularly adjustable.

A further object of this invention is to provide an auxiliary plow for breaking up heavy sludge prior to employing the scoop.

A further object of this invention is to provide a sludge removal system of the character stated in which a holddown handle is provided for the plow.

With these and other objects, the nature of which will be apparent, the invention will be more fully understood by reference to the drawings, the accompanying detailed description and the appended claims.

In the drawings: 7

FIG. 1 is a fragmentary perspective showing the sludge scoop in position for use.

FIG. 2 is a side elevation, partly in section, of one form of scoop.

FIG. 3 is a bottom plan view thereof.

FIG. 4 is an end elevation looking toward the open mouth thereof.

FIG. 5 is an end elevation of the assembly of FIG. 1.

FIG. 6 is a somewhat schematic transverse section of a tanker hold.

FIG. 7 is a side elevation of a modification of the scoop.

FIG. 8 is an end elevation of the modification of FIG. 7 looking toward the open mouth thereof.

FIG. 9 is an enlarged fragmentary perspective showing the use of the auxiliary plow.

FIG. 10 is a fragmentary side elevation of another modification of the scoop with a pivotable handle.

FIG. 11 is a fragmentary side elevation corresponding with FIG. 10 with the handle in position for pivoting.

FIG. 12 is a fragmented plan of a modified sheave assembly.

FIG. 13 is a fragmented side elevation of the sheave assembly of FIG. 12.

FIG. 14 is a fragmented plan of the sheave assembly of FIG. 12 as the cable is disengaged therefrom.

FIG. 15 is a somewhat schematic representation of the scoop being emptied.

Referring to the drawings in detail the invention, as illustrated, is embodied in apparatus for removing sludge from the bottoms of oil tanker holds and includes an elongated scoop generally indicated 5 and having flat bottom 6 and upper body portion 7 of generally circular cross section. The transverse dimensions of scoop 5 are such that the scoop will pass freely through a deck hole as will be hereinafter more fully described.

Upper body portion 7 of scoop 5 preferably is constructed from nonferrous material in order to avoid any possibility of sparks as it is pulled along the iron plates of the hold bottom. The scoop bag is preferably molded of nitril rubber.

Mouth end of the bottom 6 is configured to define downwardly slanting scraper blade 8 that lifts the sludge from the bottom plates as the scoop is pulled therealong.

Bail 9 is pivotally attached as at 10 to the mouth end of scoop 5 for attachment to hauling cable 11 by means of fastener 12. Sister hooks and other well-known fasteners could be used equally as well as the coupling, and the bail could be replaced by a wire rope bridle if desired. Various other well-known devices could also be employed for attaching scoop 5 to hauling cable 11.

Permanent bar magnet 13, having short lanyard 14, extends across bottom 6 adjacent scraper blade 8 and is slidably supported therein in suitable grooves formed in the bottom. Although the downward force acting on blade 8 will tend to hold the mouth of the scoop down as it is pulled by cable 11, the magnet will assist in such action when the scoop approaches contact with the plates of the hold.

As seen in FIG. 6, in order to operate scoop 5 mechanically, portable hoist l5 provided with winch 16 containing cable II is moved into position over deck hole l7 that opens into the hold selected for cleaning. Scoop 5 is then connected to the cable and lowered to the bottom of the hold where a previ ously stationed crewmember will bodily move it to a position adjacent transverse surge baffle 18 and intermediate a pair of channels or

ribs

19,19.

As seen in FIGS. 1 and 5, cable 11 is then reeved through the pulley or sheave 20 of an open snatch block 211 having a securing latch 22, and the snatch block is then closed and hoist 15 is then operated to haul scoop 5 along the path established by the location of the snatch block. In the embodiment of FIG. 1, as bail 9 of the scoop approaches the snatch block, the crewmember releases latch 22 thereof to permit the block to open and cause the cable to disengage from pulley 20 so that scoop 5 will be lifted upwardly to and through hole 17. As the scoop commences its upward movement, the crewmember will remove magnet 13 so that the scoop will not be attracted to and hang up against the metal surrounding the manhole.

This cycle of operations is repeated until all of the sludge in that particular path of scoop travel has been removed, after which snatch block 21 must be repositioned to clear the sludge from an adjacent path.

It should be mentioned that since the spacing between ribs 19 is generally on the order of 36 inches and that scoop 5 must be narrow enough to clear the l6-inch-diameter deck hole, it will require three paths of haul between each pair of ribs to remove all of the sludge therebetween. Accordingly, means must be provided for repositioning the snatch block after each path has been cleared.

Toward this objective (see FIGS. 1 and 5) snatch block 21 is provided with clamp 23 that adjustably secures it to transverse bar 24 that carries a pair of

adjustable clamp arms

25,25 and clamp crank 26 for releasably clamping bar 24 onto a rib 19. When clamp arms are released they may be moved to any desired position along bar 24, thus determining the direction and length of extension of the bar relative to supporting rib l9, and clamp 23 of snatch block 21 may be moved to and secured at any desired position along the extended portion of bar 24 to establish a new position of the snatch block and a new path of travel for the scoop.

Preferably, snatch block 21 should be swivel connected to its clamp 23 in order to permit sheave 20 always to lie in the same plane as that defined by the two arms of hauling cable 11 as that plane changes in angle when the snatch block is moved step by step away from vertical alignment with manhole 17, otherwise the cable would tend to jump sheave 20 or at least cause the sheave to bind against the sideplates of the snatch block. Also, the diameter of sheave 20 should be such that when snatch block 21 is secured in its operating position on bar 24, the lower rim of the sheave will be at least as low or lower than pivots 10 of ball 9 so that there will be no upward pull on the scoop as it is hauled along the bottom of the hold.

In the modification shown in FIGS. 7 and 8 of the drawings a sludge scoop generally indicated 27 includes a nonferrous metallic tubular front section 28 having a mesh-covered rubber bag 29v secured to its rear end. A scraper blade supporting frame 30 is pivotally attached to the lower front portion of front section 28 as at 31 and an edged scraper blade 32 is removably secured to the forwardly projecting portion of frame 30 by screws 33. One arm of frame 30 is provided with a spring-loaded locking pin 34 adapted to engage in a selected detent hole 35 to change the angle of setting of blade 32.

In normal scraping operation blade 32 extends beyond the periphery of front section 28 and thus would not clear the deck manhole when the scoop is hoisted therethrough. Accordingly, when hauling cable 11 is disengaged from the snatch block, locking pin 34 is moved to the lower detent hole 35 to swing blade 32 to a position entirely within the periphery of front section 28. In this position the blade edge will be at the line E of FIG. 8.

Front section 28 is provided with slanted socket 36 to receive removable handle 37 that a member of the cleaning crew can use to hold down the front end of the scoop in case the blade does not properly bite into the sludge. The handle is pulled from its socket before the scoop starts on its vertical ascent towards the deck hole.

The usual pivoted bail 38 is provided for connection with the hauling cable.

It sometimes occurs that with certain types of crude oils, or when cleaning has become overdue, the sludge becomes overly thick and dense. Under such conditions it is preferable to first break up the sludge before scooping it out.

To this end, and as shown in FIG. 9, a plow 39 having a foldable holddown handle 40, is attached to hauling cable 11 and is pulled through the caked sludge in as many passes as are required to break it up, after which handle 40 is folded and the plow removed through the deck hole. Such a plowing operation generally will require the services of two workers, one on each end of handle 40.

The embodiment depicted in FIGS. 10 and 11 includes a foldable or pivotable handle 50 which comprises fork 51 and extension 52. Two slots 53 engage two posts 54 on section 55 of scoop 56. Two lugs 57 formed on section 55 prevent counterclockwise movement of handle 50 as seen in FIG. 10. In order to move handle 50 to its collapsed or folded position, it is pulled upward whence it is free to rotate (see FIG. 11) with fork 51 clearing section 55. A clamp or hook 58 engages cable 1 1 to secure handle 50 within the front section of the scoop so that it will clear within the limiting area of hole 17 in the deck.

FIGS. 12, 13 and 14 present an alternate snatch block arrangement. Sheave 60 comprises a stationary sideplate 61 and a movable sideplate 62. Sideplate 61 has post 63 supporting pulley 64 for cable 11. This pulley is cast with a multiplicity of runoff grooves 65 on its side adjacent sideplate 62. Sideplate 61 is provided with wedge-shaped cam 66 and sideplate 62, pivotable about pin 67 has hinge pin 68 carrying integral hook 69 and cam 70 biased counterclockwise as seen in FIG. 13 by spring 71. Accordingly, as seen in FIG. 12, hook 69 engages sideplate 61. To release cable 11 from this snatch block assembly a cone-shaped actuator 72 is formed by

pieces

73, 74 clamped on to cable 11 by bolts 75. As shown in FIG. 14, cam 70 trips open first as cam 66 starts to bias cable 11 toward the open sideplate 62. With continued cam action cable 11 is caught in runoff groove 65 and the cable is freed for hauling up the scoop. The many runoff grooves are useful to cut down the cable travel between cam action and groove engagement. Cam 70 may also carry a handle for manual operation of the released mechanism.

In the embodiment shown in FIG. 15, post 10 for bail 9 has been moved down close to the center of gravity 75 of the loaded scoop. Thus the moment arm 76 is made small (compared to the previous figured location) for either manual or mechanical means to empty the scoop into container 77 for appropriate disposal.

I claim:

1. Apparatus for removing sludge from the bottom of a tank including, a hoisting winch located at the top of said tank and provided with a hauling cable extending at least to the bottom of said tank, a sludge scoop adapted to be positioned initially. at the bottom of said tank at a location remote from the vertical from said hoisting winch, holding means receiving said cable from said winch for connecting said cable to said sludge scoop, means for attaching said cable to said sludge scoop, and

forcing means for forcing the mouth of said sludge scoop towards contact with the bottom of said tank, said forcing means including a holddown handle affixed to said sludge scoop adjacent the mouth thereof, and pivot means for pivoting said handle into the profile of said mouth to reduce the clearance required by said sludge scoop for hoisting the same out of the tank.

2. The apparatus according to claim 1 wherein said pivot means comprise a pivot pin secured to the scoop and protruding from a lateral wall thereof, said holddown handle including a slot, said pivot pin being in slidable engagement with said slot for pivoting the handle about said pin between a hoist position in which the handle is located within the profile of the scoop mouth and a working position in which the handle protrudes upwardly from the scoop.

3. The apparatus according to claim 1 wherein said holddown handle comprises a bar having a grip at one end and being bifurcated at its other end, the branches of said bifurcated bar end straddling opposite sides of said scoop, each of the branches including a lengthwise slot, a pivot pin protruding from each of said scoop sides into slidable and pivotal engagement with the respective slot for pivoting the handle about said pins between a hoist position in which the handle is located within the profile of the scoop mouth and a working position in which the handle protrudes upwardly from the scoop.

4. The apparatus according to claim 3 and comprising a stop means on each of said sides of the scoop, each of said stop means being disposed relative to the respective pivot pin so as to arrest the handle in the working position and to block pivoting of the handle into the hoist position, axial lifting of the handle a predetermined distance in said working position freeing the handle from the stop means for pivoting of the handle into the hoist position.

5. The apparatus according to claim 4 wherein each of said stop means comprises a lug protruding from the respective side of the scoop, each of said lugs being disposed to engage the respective branch of the bar when the handle is in its working position and being clear of said branch when the handle is axially lifted said predetermined distance thereby freeing the handle for pivoting into the profile of the mouth of the scoop.

Claims

1. Apparatus for removing sludge from the bottom of a tank including, a hoisting winch located at the top of said tank and provided with a hauling cable extending at least to the bottom of said tank, a sludge scoop adapted to be positioned initially at the bottom of said tank at a location remote from the vertical from said hoisting winch, holding means receiving said cable from said winch for connecting said cable to said sludge scoop, means for attaching said cable to said sludge scoop, and forcing means for forcing the mouth of said sludge scoop towards contact with the bottom of said tank, said forcing means including a holddown handle affixed to said sludge scoop adjacent the mouth thereof, and pivot means for pivoting said handle into the profile of said mouth to reduce the clearance required by said sludge scoop for hoisting the same out of the tank.