US3388691A - Heater with selectively introducible steam coil - Google Patents

Description

June 18, 1968 E. R. MUCKLERATH 3,388,691

HEATER WITH SELECTIVELY INTRODUCIBLE STEAM COIL Filed Feb. 6, 1967 3 Sheets-Sheet 1 E rnesf R. Mucke/rafh IN VENTOK.

June 18, 1968 E. R. MUCKLERATH 3,388,691

HEATER WITH SELECTIVELY INTRODUCIBLE STEAM COIL June 18, 1968 E. R. MUCKLERATH HEATER WITH SELECTIVELY INTRODUCIBLE STEAM COIL 5 Sheets-Sheet 5 Filed Feb. 1967 IbkbSM .0 5D SE28 Ernest R. Mucke/rafh INVENTOR.

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ABSTRACT OF THE DISCLOSURE A heat exchange unit comprising an elongated steam coil selectively introducible into a fire chamber immediately adjacent the heat source for the production of steam. The steam coil is mounted on a jack which is automatically controlled for eifecting a selective introduction and removal of the steam coil from the fire chamber in response to changing temperature and pressure conditions.

The present invention is generally concerned with heater assemblies, and more particularly with the provision of a unique heat exchange steam producing unit in operational association with a heater assembly.

Basically, the instant invention contemplates the mounting of a steam coil on an automatically controlled jack-like supporting base for the selective raising of the steam coil into heat exchanging relationship within a fire tube or fire chamber which, in one form, may take the form of the heater assembly illustrated in applicants prior patent, No. 3,263,979. The fire tube or fire chamber will be provided with an access port in the lower portion thereof immediately forward of the burner head or fuel injection means whereby the steam coil, upon being introduced into the fire tube, will be positioned longitudinally of the burner produced flame. Further, upon the throwing of the appropriate manual switches so as to effect the necessary supply of water to the system and fluid to the control cylinder, various pressure, and also possibly temperature, controls come into operation so as to automatically extend and retract the steam coil relative to the heat source so as to maintain a constant and proper supply of steam as desired.

Such a system is to normally be associated with area heaters as set forth in the aforementioned patent. The primary object for this resides in the provision of a convenient supply of steam directly at the site of a drilling rig for use in blowing ice or snow out of the pipe as well as off the derrick floor, and also for clearing rigs and otherwise providing a rapid means for cleaning the work area and equipment. Inasmuch as all drilling and work over rigs will have a working water pump, the supply of water for the steam coil will cause no additional problems, the water merely being taken from the pump and introduced to the coil by means of a water line with at least a substantial portion of this line being laid within the housing of the heater assembly as well as within the path of the discharged heated air whether or not air directing ducts are utilized. In this manner, even when the coil is not in use, there will be no problem of water freezing within the water supply line.

Other significant objects of the instant invention reside in the provision of a steam coil unit or assembly which is of a simple positive operating construction and which, through the particular shape and orientation of the steam coil, provides for the converting of the water to steam with substantially no heat loss insofar as the main air heating function of the heater assembly is concerned.

These together with other objects and advantages which will become subsequently apparent reside in the details Patented June 18, 1968 "ice of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a perspective view of a skid mounted heater with a heat exchange assembly operatively associated therewith;

FIGURE 2 is an enlarged elevational view of access panel mounted within the heater assembly housing for enabling access to the steam coil and supporting jack mechanism;

FIGURE 3 is an enlarged partial transverse section through the burner end of the heater illustrating the construction of the steam coil and control means therefor, as Well as the two relative positions of the steam coil;

FIGURE 4 is a partial cross-sectional view taken substantially on a plane passing along line 4-4 in FIGURE 3;

FIGURE 5 is a partial cross-sectional view taken substantially on a plane passing along line 5-5 in FIGURE 3; and

FIGURE 6 is a schematic layout of the entire control system for the steam coil.

Referring now more specifically to the drawings, reference numeral 10 is used to generally designate a heater assembly which, in the preferred and illustrated form of the invention, will comprise a portable skid mounted unit utilized mainly as an air discharging area heater for drilling rigs or the like. This heater assembly 10 may follow the same general construction as that disclosed in Patent No. 3,263,979, and as such, will include an elongated fire tube 12 having one or more burner head or fuel injection units 14 mounted adjacent the intake end of the fire tube 12, and an enlarged air discharging motor driven blower 16 mounted at the discharge end of the fire tube 12. This fire tube 12 will preferably be enclosed within a protective vented housing 18 and is supported above the skid forming base by suitable support legs or the like (not illustrated).

Immediately forward of the burner head or burner heads 14, the fire tube 12 is provided with an elongated access opening or port 20 in the bottom thereof, this port 20 being of a length and width sufficient so as to accommodate a vertically movable elongated steam coil 22 selectively introduced into the fire tube 12 and into the path of the flame 24 from the burner means 14 through said access port 20. The steam coil 22, made of hollow water conveying tubing, is formed with a plurality of adjacent slightly spaced convolutions 26 defining an enlarged longitudinally extending hollow core along the length of the coil 22.

The rear convolution 26a of the coil 22 is communicated with the water supply line 28 through a rigid vertical tube section 30 and a flexible movement accommodating section 32. The forwardmost convolution 26b is communicated with the steam discharge line 34 through a rigid vertical section 36, of equal height with the rigid water line section 30, a horizontal section 38 running approximately the length of the coil 22, and a flexible movement accommodating hose section 40, suitable couplings of course being provided throughout. The water and steam line sections 30, 36 and 38 constitute a portion of the supporting frame for the coil 22. In order to complete this supporting frame a first non-communicating rigid tubular member 42 is welded to the forward convolution 26 at a point generally diametrically opposed to the point of communication with the convolution 2612 by the vertical steam line section 36. This tubular member 42 initially extends vertically so as to parallel the section 36 and subsequently extends horizontally so as to parallel the section 38, terminating in welded endagement with the lower end of the vertical water line section 36. Finally, a second non-communicating tubular support member 44 extends vertically between the rear convolution 26a and the corresponding end of the horizontal steam line section 38 defining, in conjunction with the remainder of the supporting frame elements, a pair of laterally spaced U-shaped legs.

The jack unit 46, which might be generally considered a scissors-type jack, is used to selectively raise and lower the steam coil 22 relative to the interior of the fire tube or chamber 12. This jack unit 46 comprises longitudinally spaced forward and rear jack sections 48, each including a first transverse bar 50 underlying the laterally spaced horizontal section 38 and horizontal portion of the member 42. This bar 50 is rigidly mounted through the utilization of an overlying clamp bar 52 in conjunction with a vertically extending clamping bolt and nut unit 54 which extends through both the clamping plate 52 and the transverse bar 58 therebelow as will be best appreciated from FIGURE 5. The opposed ends of each of the bars 50 are provided with depending ears 56, each of which has a first rigid'link 58 pivotally engaged therewith. A second rigid link 60 is in turn pivotally secured both to the second or lower end of each link 58 and a floor or base mounted ear 62. A transversely elongated rod 64 is r-otatably mounted between each pair of pivotally engaged links 58 and 68 associated with each jack section 48, the rod 64 being located in coaxial alignment with the axis of rotation of the pivot joint between the associated links 58 and 60. The rod 64, in this manner, helps to stabilize the corresponding jack sections 48 in addition to providing for the simultaneous control of the two pairs of links associated with each jack section 48. Both of the sections 48 are collapsed forwardly, that is the associated links 58 and 60 of each section 48 converge forwardly at an angle to each other whereby a rearward movement of the two rods 64 will effect an increase in the angle between the associated links 58 and 60 and a corresponding raising of the steam coil into the path of the flame 24 within the fire tube 12. Conversely, a forward movement of the rods 64 will result in a collapsing of the links 58 and 60 relative to each other and a corresponding lowering of the steam coil 22 out of the path of the flame 24. In order to synchronize the movement of the two jack sections 48, an elongated rigid bar 66 is afiixed between the two rods 64 at the center thereof.

The collapsing of the jack sections 48 is limited by suitable stop means which may comprise a forwardly angled bar 68 mounted, through a transverse angle member 78, on the floor or base 72, this stop bar 68 being so orientated as to be within the path of movement of the forward transverse rod 64 which engages thereagainst upon a lowering of the steam coil 22 to a preselected withdrawn position. As a secondary or alternative stop, a transverse member 74 can be aflixed to the floor 72 for engagement thereagainst by the two rear lower rigid links 60 upon an appropriate downward swinging thereof during a collapsing of the jack unit 46. The position and manner of functioning of the stops 68 and 74 will be readily appreciated from the drawings.

The actual expansion and contraction of the jack unit 46 is to be effected both by an elongated coiled tension spring 76 engaged between the forward floor mounted fixed member 78 and the rear rod 64, and a fluid, and more particularly an air piston and cylinder unit 78. The coil spring 76, engaged between the rear jack section 48, and more particularly the transverse rod 64, and a fixed point on the fioor forward of the point of engagement with the rear jack section 48, will exert a constant resilient biasing force on the jack unit 46 in a manner which will, upon the release of any force overcoming the biasing force of the spring 76, automatically effect a collapsing of the jack unit 46 and a lowering of the steam coil 22 out of heat exchange relation with the fire tube 12.

The air unit 78 is to be fixedly mounted to the supporting frame rearward of the jack assembly or unit 46 and preferably outward of the heater housing 18. The extensible piston 80 has the forward end thereof pivotally engaged with the lower end of a lever member 82 which is in turn pivotally mounted, at a central point along the length thereof, to a rigid mount 84 appropriately aflixed to the supporting framework of the heater assembly or to the heater assembly housing 18. Finally, an elongated control arm 86 extends from fixed engagement with the rear transverse rod 64 to a pivotal engagement with the upper end of the lever member 82 whereby an extension of the piston 88 will effect a rearward pivoting of the upper end of the lever 82 and a corresponding rearward and upward expansion of the jack unit 48 which in turn results in a raising of the steam coil 22. As will be appreciated, the air cylinder 78 can be single acting with the biasing spring '76, upon a release of the pressure within the cylinder 78, effecting the return of the coil 22 and a corresponding collapsing of the jack unit 46 and retraction of the piston 80. Incidently, it will of course be appreciated that the Weight of the coil 22 itself will contribute to the collapsing of the jack unit 46 upon a release of the raising pressure. This vertical movement of the steam coil 22 will obviously be accommodated by the flexible hose sections 32 and 40 provided in conjunction with the water and steam lines. Incidently, it will be noted that an elongated stabilizing and positioning bar 98 is pivotally engaged between the rear wall of the housing 18 and the rear jack section 48 for movement in a vertical plane, [thereby limiting the rearward movement of the coil 22 under the influence of the control arm 86 and translating the expanding movement of the jack 46 into a vertical projecting of the steam coil 22.

Attention is now specifically directed to FIGURE 6 wherein the control system has been schematically illustrated. Initially, a dual switch 90 is used to simultaneously close two circuits, one activating the water pump 92 which pumps the water through the water line 28 into the steam coil 22, and the other of which activates the air pump 94 for providing the necessary pressurized air utilized in conjunction with the air cylinder unit 78. The desirability of using a dual switch, or a pair of interconnected switches is to require that both the water and air supply units be turned on simultaneously. The flow of air through the line 96 from the air pump 94 is controlled by a line mounted three-way solenoid valve or the like 98, this valve 98 being in a circuit energized from the heater switch box simultaneously with an activation of the heater assembly itself. Also in series with the valve 98 and selectively effecting a making or breaking of the circuit so as to control the opening and closing of the valve 98 is both a water line mounted water pressure control 100 and a steam line mounted steam pressure control 102, the steam line 34 also including an appropriate pressure gauge and pressure relief valve. Thus, assuming an operation of the area heater assembly 10 itself, when the need for steam arises, the combined switch 90 is closed so as to activate both the water and air supply means, for example the pumps 92 and 94. When the water pressure reaches a predetermined p.s.i., for example 80, the water pressure control 100 closes the circuit and opens the valve 98 allowing the movement of the air to the cylinder unit 78. This in turn effects an extension of the piston 80 and an expansion of the jack unit 46 so as to introduce the steam coil 22 into the fire tube 12. Should the steam pressure subsequently rise to or beyond a safety setting, such as for example 100 p.s.i., the steam pressure control 102 will break the circuit and close the valve 98, thereby causing the venting of the air from the cylinder unit 78 and a dropping of the coil 22 out of the fire. Upon a decrease in the steam pressure, for example to 90 p.s.i., the steam pressure control 102 will again make the circuit, and open the valve 98 for a subsequent return movement of the coil 22 into the fire. In this manner, it will be appreciated that upon a throwing of the switch 90, assuming an initial placing of the heating apparatus into operation,

the further control of the steam producing unit will be effected entirely automatically through the provision of several safety controls which, upon a decreasing of the water pressure, or an increase of the steam pressure beyond a safety point, immediately withdraw the unit from the fire. By the same token, although not specifically illustrated, a temperature responsive control can also be provided in conjunction with the steam line 34 for making and breaking the valve circuit.

Inasmuch as the steam coil 22 and jack unit 46 are to be mounted directly below the fire tube 12, access thereto can be obtained through the provision of a vertically swinging access panel 104 constituting an adjacent portion of the wall of the heater assembly housing 18 as will be best appreciated from FIGURE 1. This access panel 104 can be retained open, supported on the hinge mounts 106, by a suitable chain and hook means 108. Further, in order to separately enclose the jack and steam coil assembly, a second inner access panel 110 can be pivoted to the base 72 for swinging movement between a first position overlying the base or floor 72 and a second vertical position enclosing the coil and jack, the access panel 110 being retained in the vertical position through engagement against a pair of angular frame members 112 by means of swinging latch-like elements 114 which have free outer ends 1116 selectively engageable within keeper means 120.

From the foregoing, it will be appreciated that a steam producing unit particularly adaptable for use with area heaters of the type herein involved has been disclosed. In operation, the steam coil itself is adjustably mounted for selective introduction into the fire chamber or tube in longitudinal alignment immediately adjacent the burner head or fuel injection means. Being so located, a relatively small steam coil need be used in that it will be orientated in what will normally be a high B.t.u. rated fire. By the same token, the longitudinal orientation of the coil provides for the desired vaporation of the water while at the same time having substantially no affect on the temperature of the air being discharged from the heating assembly, this of course constituting the main function of the heating assembly. Along these same lines, it will be appreciated that the steam producing unit can be mounted in operative relation to the heater assembly with substantially no modification thereto other than the provision of the steam coil access port. This port, incidently, may also function in increasing the efficiency of the heater assembly itself through the provision of secondary combustion supporting air. The actual retaining of the steam coil within the fire tube is contingent upon various factors, including the maintaining of a predetermined water pressure within the water line, and a safe pressure within the steam line. Upon a decrease in the water pressure, or conversely an increase in the steam pressure, the steam coil will automatically retract out of the fire.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

I claim:

1. In combination, a heating assembly and a heat exchange unit selectively introducible into heat exchanging relationship with said heating assembly, said heating assembly including a fire chamber, a heat source within said chamber, an access port defined in said chamber, selectively extensible support means supporting said heat exchange unit relative to a support base for a selective movement of said exchange unit into and out of said chamber through said port, operating means for selectively extending and retracting said support means, and automatic control means operatively associated with said operating means and automatically responsive to conditions both internal and external of said heat exchange unit for effecting an automatic operation of said operating means, said heat exchange unit comprising an elongated steam coil positioned transversely of said port for movement laterally therethrough, said heat source being orientated so as to effect a heated discharge transversely across said port within said chamber, said coil, upon movement into said chamber through said port, aligning generally longitudinally with said heated discharge.

2. The structure of claim 1 wherein said coil defines a longitudinally extending enlarged hollow core completely therethrough whereby minimum obstruction is presented to the heated discharge.

3. The structure of claim 1 wherein said support means comprises a scissors-type jack automatically biased to a collapsed coil retracting position.

4. The structure of claim 3 wherein said operating means comprises a fluid cylinder and piston unit, and a jack actuating member operatively engaged between the piston of said cylinder and piston unit and the jack.

5. The structure of claim 4 wherein said jack comprises a pair of longitudinally spaced scissors sections, each section including a pair of rigid pivotally interconnected links, means pivotally engaging one link with said steam coil, means pivotally engaging the second link of the pair with the support base, means interconnecting the pairs of links of both sections for a simultaneous movement thereof, and means resiliently biasing the links of each pair angularly toward each other to effect a reduction in the combined linear length thereof and a simultaneous movement of the coil toward the base, said operating means selectively moving the links of each pair against the biasing force and angularly away from each other so as to effect an elongation of the linear length of the links and movement of the coil away from the supporting base and into the fire chamber.

6. The structure of claim 5 including a fluid line extending from a pressurized fluid source to the fluid cylinder, valve means in said fluid line, a water line extending from a water source to said coil, and a steam discharge line extending from said coil, said control means comprising a steam pressure responsive switch in said steam line selectively operable to close said valve means upon the steam in said line reaching a predetermined pressure, the closing of said valve effecting a venting of the fluid from said cylinder to allow a retraction of said coil under the influence of the resilient biasing means.

7. The structure of claim 6 wherein said control means comprises a water pressure responsive switch in said water line for selectively opening said valve upon the water in said line reaching a predetermined pressure whereby a flow of activating fluid to said cylinder is effected.

8. In combination, a heating assembly and a heat exchange unit selectively introducible into heat exchanging relationship with said heating assembly, said heating assembly including a fire chamber, a heat source within said chamber, an access port defined in said chamber, selectively extensible support means supporting said heat exchange unit relative to a support base for a selective movement of said exchange unit into and out of said chamber through said port, operating means for selectively extending and retracting said support means, and automatic control means operatively associated with said operating means and automatically responsive to conditions both internal and external of said heat exchange unit for effecting an automatic operation of said operating means, said heat exchange unit comprising an elongated steam coil positioned transversely of said port for movement laterally therethrough, said support means comprising a scissorstype jack automatically biased to collapsed coil retracting position, said operating means comprising a fluid cylinder and piston unit, and a jack actuating member operatively engaged between the piston of said cylinder and piston unit and the jack.

9. The structure of claim 8 including a fluid line extending from a pressurized fluid source to the fluid cylinder, valve means in said fluid line, a water line extending from a water source to said coil, and a steam discharge line extending from said coil, said control means comprising a steam pressure responsive switch in said steam line selectively operable to close said valve means upon the steam in said line reaching a predetermined pressure, the closing of said valve effecting a venting of the fluid from said cylinder to allow a retraction of said coil under the influence of the biasing means.

10. In combination, a heating assembly and a heat exchange unit selectively introducible into heat exchanging relationship with said heating assembly, said heating assembly including a fire chamber, a heat source within said chamber, an access port defined in said chamber, selectively extensible support means supporting said heat exchange unit relative to a support base for a selective movement of said exchange unit into and out of said chamber through said port, operating means for selectively extending and retracting said support means, and automatic control means operatively associated with said operating means and automatically responsive to conditions both internal and external of said heat exchange unit for effecting an automatic operation of said operating means, said operating means comprising a fluid cylinder and an extensible piston associated therewith, a fluid line extending from a pressurized fluid source to the fluid cylinder, valve means in said fluid line, a water line extending from a water source to said heat exchange unit, and a steam discharge line extending from said heat exchange unit, said control means comprising a steam pressure responsive switch in said steam line selectively operable to close said valve means upon the steam in said line reaching a predetermined pressure, the closing of said valve effecting a venting of the fluid from said cylinder to allow a retraction of said heat exchange unit.

11. In combination, a heater assembly and a heat exchange unit, a water system communicated with said heat exchange unit, a steam discharge line extending from said unit, and automatic means for selectively inserting and retracting said unit relative to said assembly, said automatic means including a water pressure responsive control for activating said means, upon the achieving of a predetermined water pressure, for effecting an insertion of said unit and a retention of said unit in its inserted position, and a steam pressure responsive control for activating said means, upon reaching a predetermined steam pressure, for effecting a retraction of said unit and maintaining the unit in its retracted position.

12. A combination heating and steam producing unit comprising a support base, an elongated fire tube mounted on said base, said fire tube including an inlet end and an outlet end, burner head means mounted within said fire tube adjacent said inlet end, an elongated access port through the bottom portion of said fire tube immediately forward of said burner head means, an elongated steam coil positioned parallel to said access port, a water line communicated with one end of said steam coil, a steam discharge line communicated with the other end of said steam coil, a vertically adjustable support structure mounting said steam coil on said support base for vertical adjustment relative thereto into and out of said fire tube through said access port, said support structure including a vertically extensible and retractable jack, and means for automatically controlling the extension and retraction of said jack in response to pressure conditions within said water line and said steam line.

13. The structure of claim 12 wherein said jack comprises longitudinally spaced sets of pivotally interconnected links, the links of each set being angularly related relative to each other, said opera-ting means effecting an extension and retraction of said jack through a varying of the angular relationship between the links of each set, said operating means including means for resiliently and constantly biasing said jack to a retracted position, and means for selectively overcoming the biasing force of said biasing means and effecting an extension of said jack.

14. In combination, a heating assembly and a heat exchange unit selectively introducible into heat exchanging relationship with said heating assembly, said heating assembly including a fire chamber, a heat source communicated with said chamber, an access port defined in said chamber, selectively movable support means supporting said heat exchange unit adjacent said heating assembly for a selective movement of said heat exchange unit into and out of said chamber through said port, operating means for selectively moving said support means, and automatic control means operatively associated with said operating means and automatically responsive to predetermined conditions for effecting an automatic operation of said operating means, said heat exchange unit comprising an elongated fluid coil positioned transversely of said port for movement laterally therethrough, said heat source being orientated so as to effect heated discharge transversely across said port within said chamber, said coil, upon movement into said chamber through said port, aligning generally longitudinally with said heated discharge.

15. The structure of claim 14 wherein said coil defines a longitudinally extending enlarged hollow core completely therethrough whereby minimum obstruction is presented to the heated discharge.

References Cited UNITED STATES PATENTS 2,097,387 10/1937 Coates 122-20 2,295,115 9/1942 Keller l2220 KENNETH W. SPRAGUE, Primary Examiner.

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