US3575353A

US3575353A - Machine for applying coating material to pipe

Info

Publication number: US3575353A
Application number: US810552A
Authority: US
Inventors: Robert E Sullivan
Original assignee: International Pipe Coatings Inc
Current assignee: Lukens General Industries Inc; General Steel Industries Inc; International Pipe Coatings Inc; Energy Coatings Co
Priority date: 1969-03-26
Filing date: 1969-03-26
Publication date: 1971-04-20
Anticipated expiration: 1988-04-20
Also published as: GB1310902A; JPS5033512B1; CA921244A; NL7004475A

Abstract

A machine for coating pipe, making use of a dry mixture of coating materials, such as hydraulic cement, sand or gravel, and weight imparting material such as barite, iron oxide, or the like. The machine has a rotary impeller for projecting the dry mix from a supply source of the same toward the pipe to be coated, and includes moistening means, such as a water spray, through which the dry mixture passes after leaving the impeller to form a wet mixture which is impelled against the pipe. Means is provided for feeding the dry mix to the impeller in a substantially constant, regulated stream and for controlling the amount of water added whereby the consistency of the coating can be regulated. Mechanism is provided for causing the dry mix and water to be supplied simultaneously, automatically upon operation of the machine, and for independently regulating the flow of dry mix as well as the flow of water while the machine is in operation.

Description

United States Patent [72] Inventor Robert E. Sullivan Houston, Tex.

[21] Appl. No. 810,552

[22] Filed Mar. 26, 1969 [45] Patented Apr. 20, I971 [73] Assignee International Pipe Coatings, Inc.

[54] MACHINE FOR APPLYING COATING MATERIAL 422, 336, 379, 399, 400,543,428; 118/303, 308, (Anti-Offset Digest 1), 300 (S) [56] References Cited UNITED STATES PATENTS 2,543,5 l 7 2/1951 Anderson 239/336 3,223,329 12/1965 Ross et al 239/336 3,414,424 12/1968 Peeps et al Primary Examiner-Lloyd L. King Attorney-Charles E. Lightfoot mixture of coating materials, such as hydraulic cement, sand or gravel, and weight imparting material such as barite, iron oxide, or the like. The machine has a rotary impeller for projecting the dry mix from a supply source of the same toward the pipe to be coated, and includes moistening means, such as a water spray, through which the dry mixture passes after leaving the impeller to form a wet mixture which is impelled against the pipe.

Means is provided for feeding the dry mix to the impeller in a substantially constant, regulated stream and for controlling the amount of water added whereby the consistency of the coating can be regulated. Mechanism is provided for causing the dry mix and water to be supplied simultaneously, automatically upon operation of the machine, and for independently regulating the flow of dry mix as well as the flow of water while the machine is in operation.

, Patented April 20, 1971 3,515,353

3 Shuts-Shoot 1 Robert E. Sullivan INVENTOR ATTORNEY Patented A ril 20, 1971 3,575,353

3 Sheets-Shed 2 T FIG. 3

Robert E. Sullivan INVE N TOR ATTORNEY Patented Apfil 20, 1971 3 Sheets-Sheet 3 'mm 1' M; .I

III I II II II I II II Robe/ t E. Sullivan INVENTOR MZW ATTORNEY liil/hCllllllNlE li Ollt AIPIPILIIING COATING MATERIAL TO IPIIE BACKGROUND OF THE INVENTION In the coating of pipe, and more especially in the application to pipe of an external protective or weight imparting coating, such as heavy concrete, it has been customary heretofore to prepare a wet mixture of concrete which is then applied to the pipe by an impeller mechanism, such as rotary brushes, or the like. The wet concrete mix is usually propelled horizontally onto the pipe, while the pipe is moved longitudinally and rotated, relative to the impelling mechanism, to control the thickness of the layer of concrete which is applied. V

The coating of pipe in this manner makes it necessary to prepare large quantities of wet concrete, which is a relatively heavy material, which must be handled by the impeller mechanism, thus necessitating heavy impeller equipment, expensive to maintain and operate. Moreover, the preparation of the wet concrete mixture of the desired consistency is difficult to accomplish, substantial variations in the consistency resulting in laclt of proper adherence of the coating to the pipe, and the loss of large quantities of coating material. Changes in the consistency of the coating material are very difficult, if not impossible, to malte during the application of the material to the pipe.

A wet mixture, for use with coating apparatus of the kind heretofore commonly employed, is very difficult to prepare in the large quantities needed and having the proper consistency to secure adequate adherence to the pipe, while controlling the thickness of the coating which is applied.

Attempts have been made to employ a continuous process of mixing a wet concrete coating material for application to pipes, but due to the fact that the coating material must be prepared in very large quantities, under carefully controlled conditions, to provide a coating of constant consistency, such methods have not proven satisfactory.

SUMMARY OF THE INVENTION briefly described, the coating apparatus of the present invention comprises an impeller mechanism which may be operated to impel a dry mixed and subsequently moistened coating material against the external surface of a pipe which is being moved longitudinally and rotated at a location to receive the coating material. The coating material is supplied to the impeller mechanism by feeding means which receives the dry mix from a storage hopper, and the dry mix which is propelled toward the pipe passes through a moistening zone in which water is sprayed into the stream of dry mix to properly moisten the same to accomplish the hydration of the cement and bring the mixture to a consistency to adhere to the pipe.

The impeller mechanism is formed with a throat portion through which the dry mix moves downwardly under the influence of gravity and the additional propulsion provided by the impeller, to form a stream of material of restricted crosssectional area which then passes through the water spray so that the mixture is uniformly moistened during its propulsion toward the pipe to be coated.

Memis is provided for controlling the feed of the dry mix to the impeller mechanism, and also for controlling the amount of water which is added to the mixture after it leaves the impeller mechanism. Means is also provided for automatically supplying water to the dry mixture upon operation of the impeller mechanism, and for shutting off the supply of water when operation of the impeller mechanism ceases.

The coating mechanism may also include means for supporting the pipe to be coated for longitudinal movement and for rotation during such movement beneath the coating mechanism, whereby the thickness of the coating applied to the pipe may be closely controlled.

BRIEF DESCRIPTION OF THE VIEWS OF THE DRAWINGS FIG. I is a side elevational view, on a reduced scale, illustrating a preferred embodiment of the pipe coating machine of the invention, showing the same in position for operation in the coating of a section of pipe;

FIG. 2 is an end elevational view of the invention as illustrated in FIG. 11;

FIG. 3 is a cross-sectional view, on an enlarged scale, taken along the line 3-3 of FIG. I, looking in the direction indicated by the arrows;

FIG. 4 is a cross-sectional view, taken along the line 4-4 of FIG. 3, looking in the direction indicated by the arrows; and

FIG. 5 is a diagrammatic view illustrating the piping arrangement and control mechanism by which the supply of water to the machine is controlled and the electrical circuitry by which the operation of the machine is controlled.

DETAILED DESCRIPTION OF A PARTICULAR EMBODIMENT OF THE INVENTION The invention is illustrated herein in connection with its use for the application of a coating to the external surface of a pipe, such as the pipe P, which is suitably mounted for longitudinal movement beneath the coating apparatus and for rotation about its axis during such movement. For this purpose, the pipe is supported for rotation on wheeled carriages l0 and 12 which are movable along the trackway 14 extending beneath the coating apparatus, each of the carriages being provided with a set of spaced apart rollers, such as those shown at In and I8, upon which the pipe is supported at its ends, the rollers 116 of the carriage It) being suitably driven by any usual means such as an electric motor, whereby the pipe may be rotated about its axis.

The carriage It) is also provided with suitable means for propelling the same along the trackway M, in a usual manner. By this arrangement the pipe P may be moved longitudinally beneath the coating apparatus and rotated during such movement at any desired speed while the coating is being applied to the exterior of the pipe.

The coating applying apparatus of the invention includes a supporting frame, generally designated 20, of generally rectangular configuration, which may be suitably mounted as by means of skids 22 which are spaced apart at suitable distance for engagement with the ground on opposite sides of the tracltway Id, to support the coating applying mechanism at any desired location along the trackway and above the same. The frame 2h may include suitable means such as telescoping legs 2 3 by which the height of the frame may be adjusted to maintain the coating apparatus at a desired elevation above the pipe P.

The coating mechanism includes an impeller housing, generally designated 26, whose upper and lower ends are open, and which is supported at its lower end on cross members such as that shown at 28, of the supporting frame.

Within the impeller housing an' impeller, generally designated 30, is rotatably mounted on a shaft 32, mounted in

suitable bearings

34 and 36, and which extends at one end beyond the impeller housing for the attachment thereto of suitable means, such as a pulley an about which a driving belt it) is extended, which may be operated by any suitable means such as an electric motor 42. The impeller includes a cylindrical drum 4d suitably attached to the shaft 32 as by means of end plates as and db and to which is attached a plurality of impeller blades 50. The blades 50 are curved and of generally rectangular shape, and each of the blades is connected to the drum by means of an arm 52 adjustably connected to an external ring attached to the drum as by means of a bolt 5d whereby the angular position of the blade may be positioned as desired.

The impeller housing also has a curved wall 62 along which the impeller blades pass during the rotation of the impeller to act as a fan to cause a current of air to enter the lower end of the housing and to create a down draft through the throat 6t).

A downwardly extending, downwardly tapered hopper or chute 64 extends into the upper end of the impeller housing and is formed at its lower end with a nozzlelike discharge outlet 66 which is vertically aligned with the throat 60 to discharge a dry mixture of coating material downwardly into the throat.

Above the upper end of the trough 64 an adjustable downwardly sloping chute 68 is supported with its discharge end positioned to discharge material into the upper end of the hopper, and above the chute 68 a downwardly opening hopper 70 is movably supported for adjustment longitudinally of the chute to discharge dry mixed coating material onto the chute.

The supply hopper 70 is adapted to be filled by a belt conveyor 72 extending upwardly from the ground and which is supplied with the dry mixed coating material from any desired source such as a cement mixer or the like.

Below the discharge end of the throat 60, spaced apart parallel water supply pipes 74 are supported, extending horizontally in the direction of the longitudinal axis of the pipe P and which pipes are perforated or provided with suitable discharge nonles 76 spaced longitudinally therealong and directed to discharge a spray of water which converges downwardly to moisten the dry mixed coating material as the same is discharged from the throat toward the pipe P. The water supply pipes are supplied with water from any suitable source, such as the tank 78, through a supply conduit 80, under the control of valve mechanism to be described in detail hereinafter.

The control mechanism by which the operation of the apparatus is controlled is illustrated diagrammatically in FIG. 5 wherein the water supply pipe 80 is shown provided with valves 82 and as, between which a pressure gauge 86 is located to allow the pressure supplied through the line 80 to be adjusted as desired. The pipe 80 may also have an orifice device 88 through which water flows through a sight gauge 90, also connected into the pipe 80 and from which the water then flows to the spray pipe 74 through solenoid actuated

valves

92 and 94 by which the supply of water to the spray pipes is cut off when the impeller is not operating.

The sight guage 9%) is of a conventional-type having a float 96 located therein, past which water may flow to cause the float to rise to a height dependent upon the amount of water which flows through the gauge. By this arrangement, the amount of water flowing through the supply pipe 80 may be visually observed and the valves may be adjusted manually to maintain the flow of water at a constant volume during the operation of the apparatus.

In the operation of the apparatus, constructed as described above, a dry mixture of the coating materials to be applied, such as hydraulic cement, sand, or gravel, and protective or heavy materials, such as barite, iron oxide, or the like, is prepared in any convenient manner at the ground level and is fed into the supply hopper 70 by the elevating conveyor 72.

The outflow of the dry mix from the supply hopper 70 to the trough 64 may be conveniently controlled by adjusting the chute 68 to regulate the downward flow of material into the trough. By this means, the dry mix may be fed downwardly into the throat 60 through the lower end noule 66 of the trough at a substantially constant rate, which may be adjusted as desired.

As the downflow of dry mix takes place through the throat 60, the impeller is operated at a speed to propel the mix downwardly toward the pipe P at a desired rate, the impeller blades 50 being adjusted angular'ly so that the blades clear the wall 58 of the impeller housing at a distance which will most effectively propel the mix through the throat.

During the operation of the impeller, the impeller blades 50 act as a fan to cause a current of air to be blown in the direction of the flow of the mix to cause the mix to move toward the wall 58 of the impeller housing, thus confining the downflow of the mix and preventing the spreading or diffusion of the stream as it passes out of the lower end of the throat.

As the stream of dry mix parses downwardly from the throat 60 between the water supply pipes 743, water will be sprayed from the pipe through the nozzle 76 into the dry mix to thoroughly moisten same, the amount of water so added to the dry mix being regulated by the operator to form a coating mixture which is sufficiently moistened to properly hydrate the hydraulic cement, and having a consistency to stick on the pipe P as it is impelled against the external surface of the pipe to form a substantially uniform coating on the pipe.

In the operation of the apparatus, the operator may control the speed of rotation of the pipe, as well as its rate of longitudinal movement beneath the coating apparatus, and upon closing of the switch 100, the motor 42 will be operated to rotate the impeller at a predetermined speed while at the same time the

solenoid valves

92 and 94 will be opened to supply water to the spray pipes 74. By observing the position of the float 91 in the sight gauge 90, the operator may adjust the flow of water to the spray pipes by suitably adjusting the

valves

82 and 84 to maintain the float at a substantially constant position in the sight gauge, thus assuring a constant rate of supply of water to the dry mixture which is being impelled toward the pipe P.

By suitably regulating the movement of the pipe beneath the coating apparatus, as well as the rate at which the dry mixture is being impelled toward the pipe and the amount of water which is sprayed into the mixture, it will be apparent that the consistency of the mixture may be regulated as desired and the thickness of the coating which is applied to the pipe may be controlled.

lt is to be noted that the radius of the curvature of the impeller blades 50 may be selected, and the angle of the adjustment of these blades relative to radaii of the impeller passing through the pivot point provided by the bolts 54 may also be adjusted in a manner to provide the most efficient propelling of the mixture through the throat 60 while at the same time reducing any tendency to flow back in the impeller housing, thus enabling the coating apparatus to be readily adjusted for most efficient operation.

The coating material may be prepared as a dry mixture which is easily controlled, and which may be impelled against the external surface of a pipe while water may be added to the dry mix during its movement toward the pipe to control the consistency and hydration of the mixture just before the coating reaches the surface to which it is being applied.

Having thus clearly shown and described the invention, what is claimed as new and desired to secure by Letters Patent is:

lclaim:

1. Apparatus adapted for propelling cementitious materials onto a selected substrate and comprising: a housing having an upwardly-directed material inlet and a downwardly-directed material outlet below said inlet and aligned therewith for defining a generally-vertical path through said housing along which dry cementitious materials entering said inlet can fall on through said housing and be discharged from said outlet; material-propelling means including an impeller having a rotatable shaft operatively joumaled in said housing for rotation about a generally-horizontal axis to one side of said vertical path, and a plurality of material-propelling blades circumferentially spaced around said shaft and cooperatively arranged for rotation downwardly into said vertical path for coaction with dry cementitious materials falling therealong to propel such materials downwardly from said outlet toward a substrate spatially disposed therebelow; and means spatially disposed below said outlet and operatively arranged for introducing water into dry cementitious materials introduced into said inlet only after such materials have been propelled from said outlet by said impeller.

2. The apparatus of claim 1 further including means on said impeller adapted for selectively varying the rotational path of said blades in relation to said vertical path of cementitious materials falling through said housing.

3. The apparatus of claim 1 further including means adapted for selectively varying the angular positions of said blades on said shaft to change the rotational path of said blades in relation to said vertical path of cementitious materials falling through said housing.

4. The apparatus of claim 1 wherein saidblades are respectively curved forwardly in relation to the rotational direction of said impeller.

5. The apparatus of claim 4 further including means adapted for selectively varying the angular positions of said blades on said shaft to change the rotational path of said blades in relation to said vertical path of cementitious materials falling through said housing.

6. The apparatus of claim 1 wherein said water-introducing means include spray-producing means adapted for directing a spray of water downwardly into cementitious materials being propelled downwardly and away from said outlet.

7. The apparatus of claim 1 further including means regulating the rate at which such materials are introduced into said inlet.

Claims

2. The apparatus of claim 1 further including means on said impeller adapted for selectively varying the rotational path of said blades in relation to said vertical path of cementitious materials falling through said housing.
3. The apparatus of claim 1 further including means adapted for selectively varying the angular positions of said blades on said shaft to change the rotational path of said blades in relation to said vertical path of cementitious materials falling through said housing.
4. The apparatus of claim 1 wherein said blades are respectively curved forwardly in relation to the rotational direction of said impeller.
5. The apparatus of claim 4 further including means adapted for selectively varying the angular positions of said blades on said shaft to change the rotational path of said blades in relation to said vertical path of cementitious materials falling through said housing.
6. The apparatus of claim 1 wherein said water-introducing means include spray-producing means adapted for directing a spray of water downwardly into cementitious materials being propelled downwardly and away from said outlet.
7. The apparatus of claim 1 further including means arranged above said housing and adapted for selectively introducing dry cementitious materials into said inlet.
8. The apparatus of claim 7 wherein said water-introducing means include spray-producing means adapted for directing a spray of water downwardly into cementitious materials being propelled downwardly and away from said outlet, and control means responsive to rotation of said impeller for spraying water into such cementitious materials only so long as said impeller is being rotated.
9. The apparatus of claim 8 further including means coupled to said material-introducing means and adapted for regulating the rate at which such materials are introduced into said inlet.