JPS5926207B2 - Radiant heating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on US Pat.
099 and 3824064.

This type of heating device is highly effective and suitable for generating extremely large amounts of concentrated infrared energy.

One of the objects of the invention is to provide a new construction and operating technique for a heating device reservoir of the type described above.

According to the present invention, in the gas combustion type radiant heating device that permeates a gas mixture through a porous fireproof panel and burns the mixture ejected from the panel, while the combustion is being performed, By allowing a thin flow of relatively cool, non-flammable gas to pass through the portion of the panel proximate the support frame, the operating efficiency of the heating device can also be improved.

The flow of non-flammable gas is directed through the fire-resistant panel and includes a barrier or shield to minimize the leakage of combustible gas through the frame members supporting the panel. Acts as a membrane.

This non-flammable gas flow acts as a barrier to combustible gases, thereby providing
Reduce the importance of the seal disclosed in No. 4064,
This provides the advantage of significantly reducing burner assembly time and requiring less stringent component tolerances.

The non-flammable gas also greatly reduces the contact of hot gas products from combustion at the panel surface with the frame members, keeping the frame members cool and preventing thermal distortion.

A thin stream of relatively cool non-flammable gas is drawn by holding the porous panel on an overhanging flange carrying a combustion gas mixture-filled chamber with slots along the flange to direct the non-flammable gas from its source. It can be conveniently formed by flowing through the slot.

Another feature of the invention is that the invention comprises a back plate (lower support plate) and a tubular frame member having sides surrounding the periphery of the back plate and sealed to the back plate, defining a combustion gas mixture-filled chamber surrounded by opposite sides of the tubular frame member, the frame member having means for receiving a supply of gas into the tubular interior thereof and a porous aperture therein; and a surface for receiving a refractory panel over the full chamber.

The invention further relates to techniques for sealing heat exchange tubes to tubesheets, as well as apparatus suitable for use in such connections.

One of the objects of the present invention is to provide a method and apparatus for performing the above-mentioned sealing.

For example, relatively small all-metal heat exchangers are required for cooling lubricating oil in internal combustion engines.

In such heat exchangers, sometimes hundreds of heat exchange tubes extend between and are fluid-tightly coupled to two tube sheets.

Leakproof connections for this purpose are generally formed by a fusible sealant having a melting point temperature higher than the maximum operating temperature of the heat exchanger.

Tin/lead solder can be used as a sealant in cases where the mechanical stress is not very high and the operating temperature is close to the boiling point of water; however, in cases where the operating temperature is higher and the operating temperature is high stress. For this purpose, brazing alloys containing so-called silver solders are used.

However, conventionally, leak-proof brazing a large number of relatively small tubes to a tubesheet is a time-consuming process that requires ensuring that all joints are heated to the desired sealing temperature (melting point). However, seal leaks that occurred as a result of uneven heating during the sealing process had to be patched.

According to the present invention, one end of the six tubes of the heat exchange tube assembly is inserted and held through a tube sheet arranged in a substantially horizontal position, and all the tubes are sealed to the tube sheet on the upper surface of the tube sheet. carrying a fusible metal sealant in an amount sufficient to cause the tubesheet to adhere to the tubesheet, applying radiant heat downwardly against the tubesheet to heat the tubesheet to at least the melting point of the fusible sealant; During operation, gas is passed from above the end of each tube downward through the tube end, so that the heating is more evenly applied to the six tubes, and the sealant covers all the tubes. By providing a rapid seal to the tubesheet, a more rapid and effective seal is achieved.

The heat to melt the sealant is preferably applied by the porous (ceramic fiber) panel burner described above.

Such burners are generally described in U.S. Patent No. 344,913.
No. 7 has a ceramic fiber mat formed in the manner described in U.S. Pat. No. 3,787,194 with the ceramic fibers described in No. 7.

The heating operation according to the invention has the best heating efficiency when the burner supplying heat surrounds the top and sides of the tubesheet of the tube/tubesheet assembly.

Such an enclosed burner is preferably divided into several sections, each of which can be operated independently, so as to first heat the periphery of the tubesheet of the tube/tubesheet assembly;
It is then desirable to heat the center of the tubesheet.

A particularly effective burner configuration for this purpose includes a single ceramic fiber mat, generally in the shape of a bat, and a shallow gas-filled chamber divided into two compartments by a partition wall, one of which is one compartment is activated and air or other non-flammable gas is supplied through the inactive compartment while the other compartment is inactive.

The porous periphery of the mat ('!) is sealed with a high temperature resistant impregnant, such as water-soluble sodium silicate, and the sealed periphery is tightened in place with clamps.

A flexible sheet material, such as aluminum foil, can be interposed between the sealed periphery and the clamp.

As previously mentioned, heating devices or burners of the type described above use panels (mats) of intertwined ceramic fibers, through which the combustion gas mixture is continuously transmitted, and away from the panels. The outflowing gas mixture is combusted at the panel surface.

This combustion gas mixture spouts out in the form of a flame that covers the entire surface of the panel, and the length and height of the flame is very short, and the fibers on the panel surface near the flame are in a red-hot state or in a red-hot state. This creates a substantially continuous wall of heat that is a highly effective heat radiator.

By increasing or decreasing the flow rate and/or formulation of the combustion gas mixture, the temperature of the heated fibers can be controlled.

One of the objects of the present invention is to provide a novel heating device structure that is simple in construction and has excellent performance.

According to the invention, in a gas-fired radiant heating device of the type described above having a porous refractory panel mounted at the periphery and permeable to the combustion gas mixture throughout its thickness, no other auxiliary means are required. transmitting a thin stream of non-flammable gas, such as air, through the periphery of the panel in an amount sufficient to prevent said combustion gas mixture from escaping through the periphery of the panel; do.

The porous refractory panel can be flat, convex, concave, cupped, batted, or any other desired shape.

The construction and operation of this heating device can be further simplified by tightening the peripheral edge of the panel to a compression of at least about 10 degrees from its uncompressed thickness.

This is because such compression of the panel periphery serves to reduce the escape of the combustion gas mixture through the periphery.

Therefore, the combination of peripheral gas flow sealing and peripheral compression provides highly effective peripheral gas flow at only a fraction of the flow rate of nonflammable gas that would be required without peripheral compression. A seal is obtained.

With either of the configurations described above, no other means other than those described above are required for sealing the peripheral edge to prevent leakage of the combustion gas mixture.

That is, according to the present invention, there is no need to impregnate the peripheral edge of the panel with a sealant or to cover the peripheral edge, as in the conventional case.

The diagonal and other objects of the invention will become more apparent from the following description with reference to the accompanying drawings.

Referring to FIGS. 1 and 2, a radiant heating apparatus includes a conventional porous refractory panel 10 held at its periphery in pressure contact with a lower frame 30 by upper frame members 21.22, 23.24. It is shown.

The frame 30 consists of a four-sided tubular support member.

In FIGS. 2 and 4, only two supporting members 31, 32 are shown.

Each of these sides is hermetically secured to the periphery of the rectangular rear plate or rear support plate 400 by welding, brazing, adhesion using epoxy, or other bonding methods, as indicated by reference numeral 42 .

The rear plate 40 and the four-sided tubular support member 1 thus define a plenum chamber 38 for the combustion gas mixture supplied to the panel 10.

A connecting pipe for receiving the combustion gas mixture can be inserted into a hole provided in the rear plate 40 and welded.

Also, a baffle plate 44 may be provided to evenly distribute the gas mixture to all portions of the panel 10.

Only a portion of the baffle plate 44 is shown in FIG.

A hole is provided in the wall of the tubular support member on one or more sides of the tubular support frame 30, and a connecting pipe 53 for supplying air from a pump or a storage tank or the like is inserted into the hole. Can be welded.

Slots 55 are also formed in the top wall 57 of the support member for venting air from the interior of the tubular support member on each side through the periphery of the porous fireproof panel.

Each tubular support member is diagonally spliced at each corner of the frame 30, and the diagonal splices are sealed by welding, brazing, gluing, or other joining methods to prevent combustion gas mixture from escaping from the plenum 38. and supporting member 31.
30...To prevent uneven dilution by air passing through.

The upper frame members 21, 22, 23, 24 are each shown as angle-shaped members having an upper flange 61 overlying the outer peripheral edge of the panel 10 and a depending flange 62 secured to the lower frame member by, for example, screws 64. has been done.

The screws 64 can be threaded into the outer walls of the tubular support members 31 , 32 . . . and inserted into slots in the flanges 62 .

If it is desired to be able to adjust the spacing between the wall 57 and the flange 61, the slot provided in the seven flange 62 can be elongated in a direction perpendicular to the wall 57.

Because the porous panel 10 is transparent to the combustion gas mixture, the pressure within the plenum 38 only needs to be about 2 to 2 inches (water columns) above the ambient atmosphere and is very effective across the entire exterior surface of the panel 10. Uniform combustion can be formed.

If the air pressure inside the tubular support member is also similar to the pressure inside the plenum chamber 38, the air flow is directed to the porous panel 1.
It can pass through the 00 peripheral edge and flow out from the outer surface of the panel.

Surprisingly, the porous fibrous structure of the panel acts to avoid large variations in the width (or thickness) of the airflow therethrough.

Its action is such that the pressure pushing the air source out of the support member is 1 to 2 times the pressure pushing the combustion gas mixture out of the plenum chamber 38.
This is especially noticeable when the water column is in the high range.

This phenomenon is easily observed because during operation of the burner, the outer surface of the panel becomes red hot, but only a narrow, well-defined band around the periphery of the panel adjacent to the outer frame member does not.

Thus, the frame members are maintained at a much lower temperature than would be the case without the use of peripheral airflow as in conventional devices.

The effect is particularly pronounced when the burner is operated with the outer surface of the panel 10 lying in a substantially vertical plane or facing downward.

If the panels are positioned as described above, U.S. Pat.
In the burners of No. 8576-3 and No. 3,824,064, the extremely hot gaseous products resulting from combustion at the panel surface rise over the frame members, heating them to high temperatures.

This temperature can reach as high as 1000″F.

In contrast, the peripheral airflow of the present invention acts as a shield against the hot combustion products, thereby preventing significant amounts of the hot gases from reaching the frame members.

A peripheral airflow ('!) taken from an ambient temperature air source and flowing through a panel as thick as 1% in.

The outer surface of a steel frame member with a thickness of % in. can be maintained several hundred degrees ('F) lower than the temperature reached by a similar frame member in the burners of the above-mentioned patents.

The temperature of the frame of the heating device of the invention will be even lower than the above-mentioned temperature when used to heat an object that does not reflect as much radiant heat from the burner back to its frame members.

Yet another advantage of the present invention is that by minimizing contact of hot combustion gases to the frame members and maintaining the frame members at much lower temperatures than in the prior art, radiant heat from the frame members themselves is reduced. emissions are significantly reduced.

Therefore, the heating device of the present invention can be positioned much closer to the object to be heated than conventional devices, and moreover, the heating device can be positioned much closer to the object to be heated than conventional devices; damage to can be minimized.

This is because when the supply of fuel gas to the plenum is stopped, the porous refractory panel itself cools rapidly, and the peripheral air flow is maintained.

In contrast, the frame members of conventional heating devices take much longer to cool.

Therefore, when such heating devices are used to heat a moving web of heat-sensitive materials, they must be able to generate more heat than the web can withstand if it stops moving. Preferably, it is configured to generate much more heat.

Therefore, in conventional heating devices, in order to avoid damage to the web in the event that the web suddenly stops and it is mechanically impossible to pull the heating device away from the web, the heating device The cooling rate of the frame member is an important factor in determining how close the frame member should be placed to the web.

Since the heating device of the invention allows the frame members to be maintained at a low temperature, it is not necessary to remove the bow 1 from the web even when the web is stopped, and can therefore be installed in a relatively inexpensive manner.

(Moving the heating device so that it can be mechanically separated from the web in case of an emergency is costly).

) Additionally, locating the heating device in close proximity to the object provides more efficient heat transfer to the object and requires less fuel to achieve the desired results.

Additionally, for certain processes, such as those that evaporate moisture from a target web, the most effective radiation wavelengths range from about 32 to about 346 microns; can be obtained efficiently at low radiation temperatures.

Since the heating device of the present invention can be placed close to the target object, the radiation temperature can be lowered by that much, and the effective use of fuel energy is achieved, reducing processing efficiency. The amount of fuel used can be reduced without causing any problems.

- When the heating device is placed close to the object, it is desirable to configure the heating device to extend beyond the side edges of the object in order to increase the uniformity of the heat treatment.

Good results are obtained if the length of the extension of the heating device that projects outward from the side edge of the object is approximately equal to the separation distance from the heating device to the object.

By locating the slots 55 directly against the periphery of the panel and along the inner edges of the upper frame members 21, 22, 23, 24, the flow of the protective fluid can be directed to the desired location.

This guiding effect can be further enhanced if the edges of the panels are sealed so that too much non-flammable gas escapes laterally.

FIG. 2 shows a conventional edge sealing technique.

According to this technique, a thin aluminum foil approximately 2 mils thick
0 is wrapped around each wire of the panel, the lower surface of the aluminum foil is brought into contact with the top wall 57 of the lower frame member, and the sealant 72 is applied.
fine lines (e.g. in-situ vulcanized silicone rubber)
Seal by.

According to the present invention, if it is desired to seal the periphery of the panel, the sealant 72 can be a material such as ordinary rubber or neoprene, and there is no need to use a material that is resistant to high temperatures.

However, during normal operation of the burner of the invention, only air from inside the tubular support members 31, 32... has a tendency to escape from the periphery of the panel.

However, even if the edge seal 72 were completely omitted, such fluid leakage would not be dangerous, nor would it be economical since non-flammable fluids are not expensive.

Omitting the foil 70 would result in extensive air leakage unless the upper frames 21-24 are very tightly fitted to the support frame 30.

This peripheral airflow prevents the combustion mixture from escaping from the periphery of the panel, with or without side leakage.

The slot 55 works extremely effectively when the width is approximately %in0, but even if it is made as thin as %in0 or
In, good results can be obtained even with a very wide width.

The width (thickness) of the retrieval gas stream ejected from the face of the porous panel will generally be slightly larger than the width (thickness) of the slots 55.

If the gas pressure changes, this widening effect will also change.

Preferably, the gas pressure within the tubular frame 31, 32... is approximately equal to the pressure within the combustion mixture plenum chamber 38.

The peripheral fluid flow cooling and combustion mixture leakage prevention effects of the present invention are achieved by locating the exhaust slot 55 closer to the outer surface of the frame so that the gases exhausted from the slot partially or completely impinge on the frame flange 61. It can also be obtained by being able to point in a direction.

Most of the exhausted gas travels along the interior of the panel 10 and escapes through the inner periphery of the frame 7 flange 61.

It is not always essential to hermetically seal the portions of the tubular support members 31, 32, . . . that are screwed by the screws 64.

Even if a relatively expensive inert gas is used instead of air, there is no problem since the amount of gas leaking through the screwed part is small compared to the amount flowing out through the slot 55, but this screw The stop portion can be sealed by applying, for example, a dope for pipe threads to the screw portion to be screwed together before the two are joined together.

Alternatively, the upper and lower frames may be coupled to each other as disclosed in U.S. Pat.
It may be carried out in the manner shown in No. 4.

Instead of constructing the tubular frame 30 from four separate frame pieces, it can be formed by molding from a single sheet metal as shown in FIG.

That is, an elongated sheet metal strip □ to □ in and 1000 1000 mm thick may be formed by bending it as shown in cross-section in FIG. 2, or it may be formed by milling one wall of a standard metal tube of rectangular cross-section. The slot 55 is formed by machining, and then diagonal joint notches 81, 82, 83, 84, 85 are formed in the tube as shown in FIG.

These cutout walls 88 are not cut.

The notched tube is then bent to form a single piece tubular frame 30.

One of the four corners of frame 30 is shown in FIG.

The inner edge of each corner is welded, brazed, glued or otherwise joined as indicated at 89 and sealed over the entire height of the corner.

(Thus, the tubular frame 30 is completed, and the rear plate 4 is
0 can be joined in the same manner.

The outer surface 90 of the diagonal seam does not need to be sealed, especially if it is a tight fit.

For this purpose, the joint portion 90 is inserted from the inside of the tubular frame.
The outside surface 90 of the joint may be sealed, although a little extra leakage through the joint is acceptable, especially if there is lateral leakage from the frame periphery.

The tubular frame 30 has a slot 5 at its inner peripheral edge.
If it extends inward from 5, the porous panel 10
An additional flat support surface 73 can be formed for the slot, but does not necessarily need to extend inwardly beyond the inner circumferential edge of the slot 55.

Such a support surface 73 can be created by suitably shaping the frame tube or by milling slots 55 along the inner wall of the frame, so that the thickness of the stock metal sheet of the tubular frame is reduced. You can just do that.

FIG. 5 shows another tubular frame structure that is simple to manufacture.

In this embodiment, the support 13 is replaced by a flat support surface 73' extending towards the center of the filling chamber 38.
This is provided.

It is also useful to seal the outer periphery of the panel 10 by dipping it in a curable liquid resin or by brushing such resin onto the periphery of the panel.

This liquid resin hardens into a high temperature resistant solid.

Suitable curable materials for this purpose include silicone rubber solutions, colloidal silica solutions, and sodium silicate solutions.

With this type of perimeter seal, aluminum foil is not required.

In certain applications, the panel temperature may be high enough to damage the aluminum foil, and the reflection of heat from the surface of the object being heated by the heating device may be significant.

In such cases, other metals such as stainless steel can be used as the sealing foil.

FIG. 6 shows a heating device configuration that is particularly useful for heat treatment of running web 91, such as in drying, curing, or paper manufacturing processes of textiles.

The direction of web movement is indicated by arrow 92.

In this configuration, a series of burners 93 are placed in close proximity to each other on opposite sides of the running web and facing the web.

A re-radiator 94 is arranged directly opposite each burner 93.

The reradiator 94 has a thin layer 95 of heat absorbing material lined with a high temperature insulating material 96, such as refractory felt.

These reradiators are preferably substantially wider than the width of the burner so that in operation, the heat absorbing layer 95 absorbs a significant amount of the heat transmitted through the web 91 and becomes significantly hotter. Preferably, the heat is reradiated to the web 90.

In order to improve the drying or gas removal effect of the heat treatment process, a suction duct 97 is provided for introducing a flow of less saturated air around the area where the running web approaches the burner to the side of the web; Extracts relatively saturated airflow around the area away from the burner from the side of the web.”
A waste discharge duct 98 is provided.

To further increase the efficiency of the system, it can be configured to use the heat of the extracted air to preheat the less saturated incoming air.

The configuration of the present invention is not limited to use in combination with a flat panel 10; the panel 10 may have a convex or concave surface, such as to direct infrared radiation emanating therefrom in a particular direction. It may be made into a shape.

For example, concave panels are very convenient for concentrating radiation.

These panels are generally formed by felt-like intertwining of ceramic fibers deposited on the screen surface.

The screen surface can be shaped to fit the desired panel configuration.

Small amounts of binders, such as starch or sodium silicate, can be mixed with the fibers to stiffen and bond them together.

Referring to FIG. 7, an apparatus is shown that includes a table 110 that can be raised and lowered as indicated by arrow 121, and a radiant heater 150 disposed above the table.

A block 114 is mounted on the upper surface of the table 110 and is provided with vertical passages 116 corresponding to the number and arrangement pattern of tubes 118 to be incorporated into the heat exchanger.

The upper end of passageway 116 is enlarged as indicated at 120 to receive and position the lower portion of six tubes 118.

The lower end of the passage 116 opens at the bottom of the block 114 and faces a suction opening 122 in the table 110.

A blower 124 is carried on the table 110 and is provided with a suction tube 126 connected to a mounting ring 130 fixed around an opening 1220, such as by a flexible duct 128.

A suction pipe 126 is provided so that the suction force acting on the bottom surface of the block 114 can be controlled when the blower 124 is operated.
A butterfly valve 132 can be attached to the.

The suction pipe 126 can also be mounted in a larger suction port 129 spaced apart from the inner wall of the suction port by a web 127, so that when the blower draws suction through the suction pipe 126 during operation, the suction pipe The air around the outer peripheral wall of 126 is sucked in.

Block 114 carries a set of support members 134 positioned to surround series of tubes 118 .

Support member 134 holds tubesheet 136 at or near the upper end of tube 118.

The support member 134 has a socket 140 provided in the block 114.
A cutout 142 is provided in the lower part of the support member to allow positioning of another tube sheet 137 resting on the block 114.

Heater 150 has a generally knot-shaped porous ceramic fiber mat 152 with a recessed horizontal flange 154 that attaches to the underside of a faceplate 156.

The crest of the bat has a cylindrical portion 158 several inches in height;
A relatively shallow filling chamber 162 is provided around the peak of the bat by a nozzle 164 consisting of a hemispherical portion 160 and to which a face plate 156 is removably secured.

The filling chamber 162 is separated from the lower annular filling chamber portion 16 by a partition plate 166 extending around the inside of the housing 164.
8 and an upper hemispherical shell-shaped filling chamber portion 170.

Separate inlet nipples 171 of the sump for separately supplying the combustion mixture to these chamber parts. '172 housing 1
64.

In the illustrated embodiment, the housing 164 consists of a lower cylindrical portion 174 and an upper hemispherical portion 176.

Outwardly projecting flanges 178 and 180 at the joints of these housing sections connect the entire housing and serve as mounting structures to hold the divider plate 166 in place. accomplish

To this end, a plurality of bolts are inserted through a series of alignment holes formed in the flanges 178, 180 and the partition plate 166.
82 and screw nuts 184 onto these bolts to connect the flange and partition plate.

These bolts 182 are suitably placed around the housing and extend downwardly through the mounting holes in the face plate 156 to secure the face plate.

A nut 186 is screwed onto the lower end of the bolt.

This burner first has a housing part 166°174.1
76 is assembled, and then a preformed and prepared mat 152 is press-fitted into the assembly to firmly engage the inner shield of the partition plate 166, and the face plate 156 is then secured.

The shield portion of the partition plate 166 may be curved upward as shown at 167 to provide a better seal to the mat.

The flange portion 154 of the mat is held against an inwardly projecting flange or bulge plate 188 at the lower end of the lower housing portion 174 to seal the edges of the mat against gas leakage.

A cylindrical flange 190 integrally projects upwardly from the top surface of faceplate 156 surrounds the edges of the mat and fits tightly around the lower edge of the housing.

so that the upper end of the tube/tubesheet assembly can be inserted into the burner slightly above the opening in mat 152.
A center hole 19 in the face plate 156 that is slightly larger than the opening of the mat
2 is provided.

The hole 192 also has a working space 191 surrounded by a mat.
Allows gas to enter and exit.

Since this burner is operated by a combustion gas mixture, the area where the gas mixture can leak from the burner is
It is advisable to keep everything sealed.

Thus, between housing members 164 and 166 and 166
The connection between and 174 is made by a gas get or
As shown, sealing can be achieved by applying liquid silicone, which becomes a solid sealant when cured.

Also, the upper surface 194 and lower surface 1 of the peripheral edge of the matte flange 154
95 and the side edges 196 are bent and wrapped with aluminum foil 193, and the aluminum foil is sealed to the overhanging plate 188 with a sealant such as curable liquid silicone rubber.

The pores in the outer portion of the mat flange 154 can also be plugged, for example, by impregnation with an in-situ drying aqueous sodium silicate or an in-situ hardening liquid silicone rubber, as shown at 197. can.

Furthermore, it is desirable to water-cool the outer periphery of the face plate 156, for example, by brazing a water cooling coil 198 to the lower surface of the face plate.

To operate the apparatus shown in FIG. 7, six tubes 118 (actually, more tubes are provided than shown in the figure) are fitted onto the table 110, and a certain amount of powder or granular liquid is inserted into the table 110. A fusible sealant 199 is spread over the surface of the upper tube sheet 136.

The blower 124 is started and the table 110 is raised to the position shown so that the upper surface and side edges of the upper tubesheet 136 are surrounded by the burners.

The burner sections 158, 160 are then activated and the suction control valve 132 is opened.

The tube 118 is made of copper or brass with a wall thickness of 30 mils, and the upper tubesheet 136 is made of copper, brass or steel with a width of 8 inches and a wall thickness of about 90 mils, and the burner produces about 130.000 BTU/
Sealant 199 consisting of copper/phosphoric acid flux or silver/copper flux, when combusting a mixture of about 30%
It melts in seconds or less and flows into the gap between the outer circumferential surface of the tube 118 and the tube receiver section of the tube sheet, regardless of the number of tubes.
6 tubes are sealed to the tube plate 136.

Care should be taken when applying the fusible sealant to ensure that excess sealant does not clog the tube 118.

Blockages in the tubes can impede the flow of hot gas through the tubes, resulting in uneven heating.

Immediately after completing the tube sealing operation to avoid overheating.
Stop Ina.

However, suction l using a blower may be continued.

Continuing this suction cools the extremely heated tube/tubesheet assembly and further reduces surface oxidation phenomena.

Without suction during heating by the burner, the temperature rise of the tubesheet would not be uniform and much more time would be required for all parts of the tubesheet to be hot enough to melt the sealant 199, causing the tube By the time all portions of the plate are sufficiently heated, the outer portions of the tubesheet may become severely overheated and the tubesheet may also become sealed to the support member 134, although not significantly damaged. .

Such unfavorable sealing occurs even if the upper end of the support member is formed of approximately 1.5 in. thick steel.

In contrast, if the combustion gas products are drawn through tube 118 at a lower rate, on the order of about % feet per second, the temperature increase will be uniform and hot enough to seal the upper end of support member 134 to the tubesheet. Long ago, the sealing of all tubes 118 is completed.

The portion of the tubesheet that is contacted by support member 134 is
Regardless of whether there is a suction flow of the combustion gas products, they will not heat up as quickly, thereby slightly delaying the temperature rise of the portion of the tubesheet adjacent to the support member.

Therefore, for good results, it is desirable to space tube 118 at least 9 inches apart from all supports 134.

These support members may also carry special attachment members that increase the mass of their ends 1 to further increase thermal inertia, but the 6 tubes 118 are spaced 6% in from the upper ends of the support members. That alone is enough.

If there is significant hardware around the periphery of the tubesheet, the lower section 158 of the burner 150 may be started first before the upper section 160 is started, and after a few seconds, the periphery of the tubesheet is brought to sealing temperature. It is ingenious to start the upper section 160 after it has absorbed enough heat until it is fairly close.

To prevent malfunction, only air without fuel is blown through the upper section 160 while only the lower section 158 is being combusted without the upper section 160 being combusted.

This effectively balances the pressure on both sides of the partition plate 166, thereby inhibiting the flow of combustion gas to areas where it could be accidentally ignited.

Closing the pores of the mat, as indicated at 197, also avoids localized deposition of stagnant combustion mixture.

There is no practical upper limit to the velocity of hot combustion gases drawn downward through tube 118.

There does not need to be a gas-tight connection between tube 118 and passageway 116 in block 114.

In fact, as shown in the figure, the suction tube 126 and the suction port 129
By creating an open gap between the
It is a good idea to prevent the blower from overheating.

The tube 118 is not particularly thick per se, and typically has an inner diameter of %i.
n, it is difficult to make the gas velocity through them extremely high.

A speed of 20 feet/sec is suitable.

The arrival achieved in a fraction of a minute in accordance with the present invention is much greater than the sealing which takes 245 minutes without flowing the combustion gases down through the tube 118. It has been found that there are fewer defects.

Furthermore, according to the present invention 1, the heating temperature is much more uniform, and the melting and flow of the sealant is also more uniform.
The amount of densifying agent required is small.

In accordance with the present invention, approximately half the amount of sealant typically required in the prior art is required.

Thus, when sealing a tube to a tubesheet hole having an outside diameter approximately 2 mils less than the diameter of the tubesheet receiving hole, according to the present invention:
Only about 1 gram of sealant is required per square inch of tubesheet surface.

FIG. 8 shows a modified embodiment of the sealing device of the invention.

In this embodiment, a generally flat burner surface 152
A burner 150 is used.

This burner configuration requires a slightly longer temperature rise time than the configuration of Figure 7, so for wider tube/tubesheet assemblies, the time required to seal the tubes may be longer than the configuration of Figure 7. 50% more
Although the process may take longer, it still takes much less time than with traditional methods.

The burner 150 of FIG. 8 may be configured as previously described and preferably in the manner shown in FIG. 5.

That is, a frame equipped with a tubular member through which an inert gas flows is simply fitted around the periphery of a ceramic fiber mat, and the inert gas passed through the periphery of the mat causes the periphery of the mat to become a smoldering gas mixture. It is constructed in such a way that it functions to seal the body against leakage.

In this case, there is no need for any other sealing means at the periphery.

In the configuration of FIG.
6.

The casing 119 forms the shell of the heat exchange device that cooperates with the tube/tubesheet assembly.

The tube/tubesheet assembly can be sealed in about 30 seconds, after which the assembly is turned upside down and the opposite end is similarly sealed.

Thereafter, both the upper and lower tube plates 136 and 137 are soldered or welded to the periphery of the casing or shell 119.

If the shell 119 is made of thin steel, it can be sealed to the tube sheet at the same time as the tube 118 is sealed.

In this case, it is preferable to perform the sealing using the enclosed burner shown in FIG.

While suction as described above is a convenient technique for forcing hot combustion gases through tube 118, such gases may also be forced down through tube 118 by being pumped from above.

For example, the frame of the burner of FIG. 8 can be provided with a cylindrical depending extension having an asbestos lining pad surrounding and clinging to the shell 119.

With this configuration, when the burner is operated, the high temperature combustion gas is
Since there is virtually no escape other than tube 118, it is pumped downward through tube 118.

For the purposes of the invention, soldering is considered as the sealing process.

That is, a metal having a melting point of at least about 450 degrees Fahrenheit is used as a sealant, typically an alloy of 45% silver and 55% copper (by weight).

Wax temperatures can reach as high as 13,000F or more.

Borax is often added along with the braze joint area to protect the braze joint area and the parts being joined from excessive oxidation and to improve wetting of the joint area by the molten braze joint area.
A flux such as (rax) is used.

There are also braze joint areas that can be used without flux, such as copper/phosphorus alloys or other metals.

The sealing apparatus of the present invention can be operated continuously to seal a series of tube/tubesheet assemblies one after another, but for short periods of time to melt and flow the sealing metal into place. It is clever to activate it only during the period.

Therefore, the heating device can be completely stopped between one sealing operation and the next sealing operation.

In this regard, ceramic fiber burners are suitable for such intermittent operation because they heat up and cool down in just a few seconds.

In order to carry out such intermittent operation, the fill chamber of the burner should have a relatively small volume, preferably a depth of about i y2
It is preferable not to exceed r n.

In this way, when combustion gas is intermittently supplied to the filled chamber, the gas quickly reaches the ejection surface of the fiber mat to be burned, which simplifies the timing of burner operation. be done.

so that it ignites each time the supply of combustion gas is started.
An ignition device, such as a pilot light assembly or an electric spark ignition device, can be mounted near the periphery of the burner.

A configurable automatic opening/closing sequencer can be used to time the gas supply to each section of the burner (158-160) and the operation of the suction blower.

Instead of raising and lowering the table 110 once to bring the workpiece closer to the burner, in addition to raising and lowering the table 110 by a certain IAi, the burner may be moved toward or away from the table.

In the configuration of FIG. 8, /<-
There is no need to make vertical movements for the seat.

In addition, in the configuration shown in FIG. 7, an auxiliary heating device is provided that surrounds and above the lower tube sheet 137, and when the tube/tube sheet assembly is held in the position shown in FIG. The heating device can be activated to seal the lower end of the tube 118 to the tubesheet 137, in which case a layer of sealant is deposited on the upper surface of the lower tubesheet, with the lower tubesheet having a lower end than the upper tubesheet. If it takes a long time to raise the temperature, the auxiliary heating device may be started before the heating burner 150.

If the pores at the periphery of the ceramic fiber mat are sufficiently sealed with silicone or sodium silicate or other alkali metal silicate impregnating agent, it is not necessary to wrap aluminum foil 193 around the periphery of the mat. It is sufficient to clamp the peripheral edge and fasten it in a predetermined position.

Of course, further aluminum foil or other gaskets may be inserted between the periphery of the mat and the periphery of the plenum, and silicone or alkali metal gaskets may be added to seal the periphery of the mat to the plenum. Silicates can also be used.

FIG. 9 shows a heating device 200 with improved peripheral sealing.
shows.

The heating device 200 has a knob-shaped panel 202 of intertwined felt-like refractory fibers as described above, and the peripheral edge of the panel is covered with relatively thick stainless steel having a thickness of approximately Support assembly 2 made of steel or other metal
Tighten around 04.

A central dish 206 is provided having a floor 205 and an inclined wall 207 with a projecting edge 208 against which a panel 202 is pressed to define a chamber 210 filled with a combustion gas mixture.

The outer surface 203 of the panel 202 is rectangular and the filling chamber 21
0 is also a rectangle.

At the outer periphery of the floor 205 of the dish 206 is a series of chevrons (only two chevrons are designated 212 and 214 in FIG. 9) that define the support assembly or rectangular frame 204.
(as shown).

The periphery 220 of the panel 202 is the rectangular frame 2
It is fitted into 04.

These chevron-shaped members include a horizontal web 222 welded or brazed to the floor 205 of the dish 206 and a flange 2 of the dish.
08, but is shown as having a vertical web 224 extending close to, but not quite as far as.

The frame chevron cooperates with the side wall 207 of the dish to define an outer fill chamber 230 that surrounds the combustion mixture fill chamber 210 and has an evacuation slot 232 that is engaged by the periphery of the panel 202.

These frame members are joined at each corner of the frame by diagonal joints or otherwise to minimize or completely seal leakage of the outer fill chamber.

An opening in the floor 205 is fitted with a supply nipple 246 for delivering a combustion gas mixture, and the frame chevron 212
--Equipped with a supply nipple 248 for supplying non-combustible gas to the opening provided in one or more of the parts.

Also, a baffle plate, such as a U-shaped baffle plate 216, may be provided to evenly distribute the incoming gas mixture.

Since air is generally used as the nonflammable gas to be passed through the outer filling chamber 230, even a slight leakage causes no particular inconvenience other than a slight increase in air consumption.

Clamping the panel 202 against the frame chevrons and securing it in place is shown as being accomplished using a series of four or more clamping chevrons (clamps) 236,238.

That is, the peripheral edge 220 of the panel 202 is sandwiched between the frame chevron members 212, 214 and the tightening chevron members 236, 238, and the screws 240 are inserted into the aligned holes of the chevron members. and the web 224 of the frame chevron member.
A locking nut 24 fixed by clipping or welding to
2, the panel 202 is fixed.

These screws 240 (which need not be thicker than approximately %in) can be easily threaded through the panel periphery without appreciable damage to the panel 202 and prevent gas leaks around the panel periphery. Any such damage, if any, is compensated for by sufficiently tightening the clamp 236 to compress the panel periphery.

A typical panel has a wall thickness of approximately 13 Ain, with small interfiber voids such that more than half of the thickness is occupied by the fibers and binder, reducing the total thickness by only about 10%. Compressing the panel periphery to reduce it greatly reduces interfiber voids and limits fluid leakage.

Very good panels of felted intertwined fibers can be formed by threading mats of such fibers without the aid of binders.

Panels formed by such stitching are extremely flexible compared to molded, board-like, rigid bond-containing mats, and their peripheries are approximately 30 mm thicker than their normal thickness. It can be compressed to %.

Compressing the approximately 1 in. thick periphery to approximately % in. provides a backstop that is extremely effective as an air seal.

In the case of such flexible panels, it is preferred to compress the periphery of the panel to about half or less of its original thickness.

However, in the case of a flexible panel, only the peripheral edge of the panel or the entire panel can be made rigid by impregnating it with an aqueous solution of starch or the like.

When stiffened in this way, the degree of compression of the panel periphery can be reduced.

In order to reduce the effect that such compaction may have in terms of breaking the binder-impregnated panel fibers, the panel periphery to be compacted may be compressed with water or other means that dissolve the binder within the fibers. immerse it in a solvent.

Due to this moisture, the panel periphery becomes easily deformed, so
The panel periphery can be easily compressed without applying too much stress to the clamp member.

To ensure uniform compression of such plate-like panels, the spacing between each screw 240 is approximately 8 inches or less when the clamp chevron members 212, 236 have the thicknesses described above.

The heating device 200 is operated in a closed space and therefore
If the clamping angles are subject to significant reflected heat, it is preferable to drill slots approximately 6 inches apart in the vertical webs of the angles to allow them to heat shrink without distortion. I have a cough.

Such slots may be as wide as approximately 20 mils, but such slots may be approximately 20 mils wide if the angle members do not engage each other at the corners of the frame and are open to thermal expansion. It can be exempted.

One feature of the heater structure of FIG. 9 is that multiple heaters can be juxtaposed to form an effectively continuous radiant heater assembly to cover a large area.

Accordingly, each heater is conveniently constructed to have a rectangular heating surface approximately 1 x 2 feet.

Larger dimensions of the rigid plate-like panels make manufacturing somewhat more difficult as they become difficult to mold and handle.

Form a panel of relatively small dimensions such that the perimeter edge 220 of the panel is folded down at least about 90 degrees from the plane of the panel body (the perimeter edge 220 can be thought of as a flange folded down from a flat sheet) However, by arranging the peripheral mounting members so that they are at least partially inside the outer surface of the flange 220 and do not protrude more than about 5 mm beyond the outer surface, the heaters 200 can be configured as shown in FIG. juxtaposed in a highly desirable manner as shown.

In FIG. 10, an assembly 251 of individual heaters 200 is arranged with five adjacent panel edges 220 spaced apart by about 3 mm, as indicated by 252.

Although the panel surface 203 can be formed with a substantially zero radius of curvature where it bends into the peripheral edge 220, it is easier to round the bend to a radius of curvature of about % in. There are cases.

The above 3 mm spacing of such rounded corners is not a particularly convenient factor in constructing an effective continuous heating surface.

The 3 mm spacing is not disadvantageous, especially if the gas mixture is to be burned over the entire rounded corner.

Increasing the spacing from about 3 mm to about 5 mm results in a significant discontinuity in radiation uniformity, which is generally acceptable.

Although the tightening screw 240 is shown as having a round head and protruding from the side of the fireproof panel periphery,
Such protrusion is not a problem as long as it does not exceed the 5 mm limit or the 3 mm limit mentioned above.

These screws are arranged asymmetrically along the side edges of the panel so that the screws of one heater and the screws of the adjacent force a heater are in a staggered relationship with each other, as shown in FIG. can be placed in

In practice, hexagonal socket head screws, which protrude slightly larger but are easier to install, can be used instead of round head screws.

Alternatively, if it is desired to minimize or eliminate the spacing 252, a countersunk head screw may be used with a countersink in the clamp angle member 236, 238-m so that the screw head does not protrude from the clamp angle member 236, 238-m-. It can be fitted into a hole.

The burner structure of FIG. 9 may also use the embroidered flexible panels described above.

The behavior of such flexible panels is similar to a blanket, the edges of which can be folded and pushed between side anchoring members (clamping members).

The corners of such panels have a high degree of flexibility and can be compressed into a desired shape, but the protruding parts of the corners can be cut out or cuts made there. Tighten the panel in place by
It is preferable to facilitate clamping.

However, in order to prevent gas leakage from the notch, such a notch is preferably limited to the portion of the corner that is handled by the mooring member.

It is not necessary to form the bending flange 220 on the entire periphery of each fireproof panel 202.

Each panel in FIG. 10 has at least one edge that is not juxtaposed with other panels, and some panels have two non-juxtaposed edges.

If only two panels are juxtaposed, one of each panel
Only the edges need be provided with folding flanges 220; the remaining three edges can be of flat panel construction as described above and shown in FIGS. 11 and 12.

The juxtaposition is made very close by molding or shaping the side edges 220 to be juxtaposed so that they are folded down by more than 90 degrees from the horizontal as measured at the corner 250 shown in FIG. can do.

For this purpose, a panel is formed around a suitably shaped molding screen, and up to three of its four sides are bent at 100 or 110 degrees, measuring at the corner 250, to create a fold-down flange. , and then slide the thus formed panel away from the fourth side of the mold (screen) (ie, the side on which the folded edge was not formed) and pull it apart.

If a folded flange is desired on only one side, the flange edge can be formed when the panel is molded, or it can be made flexible by moistening one side edge of the flat-formed panel. It may also be formed by bending it later.

The structure of FIGS. 11 and 12 is a flat heater panel reservoir structure that is easily fabricated from readily available hanging sheet metal.

The structure has a panel support consisting of a welded assembly of a rectangular fill chamber box 302 and a surrounding hollow gas fill tube 304 of rectangular cross section.

The full chamber box 302 is formed by appropriately making score lines at the four corners of a rectangular sheet, folding the four flaps formed by the cut lines upward, and welding the corners in an airtight state. is convenient.

A hole is then drilled in the floor of the box and a PTM half-closed nipple 306 is hermetically welded into the hole.

Also, a baffle plate 308 can be spot welded over the hole to evenly distribute the combustion gas mixture supplied through the hole.

If desired, an additional hole 310 can be provided in the floor of the box for inserting a pressure gauge or the like.

The tubular fill chamber 304 can be easily made by folding sheet metal into a channel having a web 312 and upper and lower flanges 314, 31, and 6 of different widths.

This channel is divided into four sections, each formed with a diagonal seam, which are welded together in a gas-tight manner, if necessary.

The tubular fill chamber can then be attached to the fill chamber box, for example, by spot welding its flange 316 to the floor of the box 302.

This tubular filling chamber also has a gas inlet tube 320 in the form of a half-closed nipple, as in the filling chamber box 302.
In addition, a spare insertion port 322 can be provided, and a baffle plate 324 can be fixed to the outer surface of the box 302 or the inner surface of the tubular filling chamber by spot welding so as to cover the inlet pipe 320.

A slot 330, preferably %in1 wide, is formed around the top of the box-shaped filling chamber 302.

The refractory matrix or panel 340 includes a clamping frame 34 having a rectangular cross section as shown in FIG.
2.

The frame 342 has a slit 344 (FIG. 12) in the web portion that rests on the exterior surface of the panel.

These slits may be spaced approximately 811 cm apart and preferably have a width of % in. to accommodate even the most severe thermal conditions.

The clamp frame 342 can be fixed with screws 346 as in the structure of FIG. 9, but sheet metal screws can be used in both this structure and the structure of FIG. In that case the nut can be omitted and a lock washer can be fitted under the screw head if desired.

When operating the burner panel with the combustion surface facing downward,
In severe thermal conditions, such as when operating a pair of burners face-to-face, the clamp frame 342 may be covered with high-temperature insulation, such as a mineral fiber felt or embroidered blanket. It is desirable to insulate the clamp frame from radiant and convective heat by doing so.

In the configuration of FIG. 11, there are three Ai ports. One end of the thick fiber plankera l-350 is sandwiched between the clamp frame 342 and the top surface of the refractory 7 trix 340, and the blanket is folded back over the frame 342 and the web 312.
and is secured to the flange 316 with a clamp 360 and a sheet metal screw or other screw 362.

The fiber blanket 350 isolates the clamp frame from convective heat and, because it is pure white, reflects radiant energy from the opposing burners, making the system more efficient.

In very high ambient temperature operating conditions, it is desirable to completely cover the non-radiating surfaces of the burner with a fiber blanket.

FIG. 13 shows a fiber blanket 35 having a push-in edge 370 for insertion under the plane of the clamp frame 342.
Indicates 0.

Under relatively mild usage conditions, simply frame 3
It may be desirable to cover the sides of 42 and hold the blanket in place by screws 346 and washers mounted under their heads.

The radiant heating device of the present invention can be equipped with an automatic igniter such as an electric spark igniter or a pilot light.

Figures 14 and 15 illustrate a particularly preferred automatic igniter construction for mounting on a heating device of the type illustrated in Figures 11 and 12.

That is, a spark rod 501, a ground rod 502, and a flame inspection rod 50.
The standard assembly 500 with the porous fire resistant panel 340 is mounted so that the rods are approximately parallel to and about % in above the outer surface 505 of the porous fire resistant panel 340.

A partition plate 507 is provided below the inner surface of the lower panel of the rod assembly 500 to separate the chamber 5 from other spaces within the box-shaped filling chamber.
Isolate 09.

Chamber 509 is fitted with its own supply connection 511 for receiving a separate combustion gas mixture.

Each of the spark rod 501 and the flame check rod 503 is attached to a top flange 520 of the frame 342 and a flange 3i6 of the plenum chamber 304 in alignment therewith as shown in FIG.
, 314 within two similar insulating members 550 installed through openings drilled in them.

Ground rod 502 is welded or brazed to flange 520.

The ends of the rods 501, 503 near the flange 316 are threaded to hold the rods in place and to receive fittings forming connections for the necessary wiring. It is.

The structure of Figures 14-15 is activated using a safety check device to start the burner.

That is, a separate pilot combustion mixture is provided into chamber 509 while simultaneously energizing spark rod 501 to generate a spark.

If the hanger 503 does not sense a flame for a short period of time, for example within 10 to 30 seconds, the flow of combustion mixture is automatically shut off and the start sequence operation is manually restarted.

Preferably, the start-up sequence operation begins after checking the flow of the combustion mixture, for example by expelling the gas in chamber 509.

This starting operation ignites the separate combustion mixture, and the flame check rod 503 senses the ignition and opens the valve, supplying the main combustion mixture into the filling chamber 302 and causing the flame in the chamber 509 to flow. The main combustion mixture is ignited by.

By using a small chamber 509 with a low BTU 7 input to test for automatic ignition, the risk of explosion during ignition is minimized.

A chamber volume of about 100 i or less is very effective for this purpose.

The pilot combustion on the radiant surface of the panel also contributes to the overall radiant heat of the burner.

The clearance from the refractory panel is small so that the rods 501, 502, 503 do not get in the way when the radiant surface of the burner is placed close to the object to be heated, for example a running textile web to be dried. It is preferable.

The closer the heater is to the object to be treated, the better the efficiency of the heater, so the gap between the object to be treated and the panel should be 2 inches,
or even less.

FIG. 16 depicts a radiant heating apparatus 700 of the present invention that is particularly adapted for sealing metal tubes to tube sheets based on the sealing techniques previously described.

The heating device 700 has a dome-shaped retainer 702 that fits over the edge 710 of a hat-shaped refractory ceramic panel 720 and is hermetically welded to a support ring 7041 formed to receive it.

Thus, the peak portion 712 of the panel forms the dome-shaped retainer 7.
The mountain portion 712 is held in a spaced relationship with respect to 02.
a filling chamber 73 for the combustion mixture to be combusted on the convex surface of the
Define 0.

An inlet lower 32 and a pressure gauge insertion lower 34 are attached to the retainer 702 as shown. The edge 710 of the panel 720 is secured by a clamp ring 106 bolted to an extension 708 of the support ring 704. Shown as being clamped to support ring 704.

An extension 708 of ring 704 is displaced from panel edge 710 to form a cylindrical wall 740 that defines an annular fill chamber 750 for combustion gases.

If desired, this displacement portion can be integrally formed with the clamp ring 706 and the extension 708 of the support ring 704 can be configured to lie in the plane of the main body portion of the support ring.

Alternatively, walls 740 can be separated into separate rings 704 and 7, respectively.
06 may be divided into an upper cylindrical portion and a lower cylindrical portion formed as an integral part.

This annular filling chamber 750 is also provided with an inlet arrow 0 and a pressure gauge insertion lower 70.

Radiant heating device 700 can be used in place of the heating device shown in FIG. 7, but with only one combustion zone.

The non-flammable gas being pumped into the fill chamber 750 of the heating device 700 flows through the edge 710 of the porous refractory panel 720, and the combustible gas mixture supplied through the fill chamber 730 flows inside the panel. Prevent it from reaching the lowest part of the surface that is aligned with the filling chamber 750.

The non-flammable gas escaping from the inner lower portion of the panel flows outwardly along the bottom surface of the clamp ring 706, keeping the ring and its associated metal parts sufficiently cool that the thermal heating device γ00 is There is no need for external cooling coils or jackets.

The retainer 702 and other members that hold the panel 720 may all be formed from approximately 60 mil thick aluminum.

Another feature of the invention is that such an air-tight configuration (
The heating device is particularly suitable for use in domestic hot air and/or hot water furnaces.

The air seal of the present invention effectively prevents the diffusion of combustion gases to the edges of the porous panel.

Diffusion of the gas mixture towards the edge of the panel causes the gas to burn at a low feed rate, thus backburning deep into the binder holding the refractory fibers and ultimately This will form lines of weakness in the panel, and if the panel has not been needled, it is likely to break from there.

In fact, such flashbacks can proceed so deeply as to ignite the interior of the combustion mixture chamber itself, rendering the heating device unfit for further operation. Make it.

The edge-sealing arrangement of the present invention in this sense significantly extends the useful life of the fire-resistant panel, and is also suitable for relatively small domestic installations due to its simple construction and low manufacturing costs.

Figures 17 and 18 show a hot air heat exchanger structure for a domestic heating device according to the invention.

The heat exchanger 800 is cylindrical and has a hollow interior 802 that houses a generally cylindrical fibrous panel 804 therein.

The open end 806 of the panel is secured to the mounting plate 808 by ribs 810 formed or welded to the mounting plate.

That is, the panel end 806 is abutted around the rib 810 and the panel end is tightened by pulling the ends of the split sheet metal strap 812 together with the tightening screw 814.

Before snapping the panel into place, insert the partition disc 820.
A male threaded extension end 824 of a tubular support member 822 attached thereto is screwed into a threaded hole 826 in the mounting plate 808, thereby fixing it to the mounting plate.

The periphery of partition disk 820 is positioned directly above the edge of rib 810 and is configured to define a periphery slot 830 for venting sealing gas to the periphery of panel 804 .

A sealing chamber 84 under the disk 820 that partitions the sealing gas flow.
Mounting plate 808 for artificial nipple 832 for feeding to 0
Connect through.

Extension end 824 constitutes a conduit for supplying combustion gas mixture to plenum chamber 850 .

Strap 812 is also shown carrying a series of protruding ears 842 arranged in a circular arrangement.

These ears are attached to the insulation packing 844 when the mounting plate 808 is inserted into and engaged with the opening 846 of the heat exchanger 800.
around the open end of panel 804.

Some of the ears 842 are provided with holes for receiving an ignition and service assembly 860, shown as consisting of a series of ceramic tubes 862 with enlarged portions 865.

6 tube 862 is attached to the mounting plate 808 which is aligned with the hole in the ear piece 842.
screw into the hole.

A rod 867 having a disc-shaped inner end 870 is inserted through the hole in each ceramic tube and positioned in the proper position relative to the ceramic tube by providing an enlarged portion 872 on the rod.

A sliding washer 874 may be fitted to the rod prior to insertion to facilitate positioning cooperation between the conduit and the enlarged portion 872 of the rod as it is inserted into the ceramic tube.

The outer end of each rod can be threaded into a mounting tip 876.

The discs 870 of each rod are arranged edge-to-edge to suit spark generation and flame detection, as described in connection with FIGS. 14 and 15.

Heat exchanger 800 can be located within the air-filled chamber of a standard domestic heating device or, if desired, within a water tank containing the water to be heated.

The heat exchanger can be of metal or glass construction, but silicate glass is particularly suitable when used to heat water.

The water to be heated in this way can be colored, for example with dyes, in order to better absorb the radiant energy transmitted through the transparent heat exchanger.

In the case of metal heat exchangers, increasing their effective surface,
It is desirable to provide ribs to increase heat transfer to the surrounding air and the like.

Another feature of the present invention is that inert or reducing gases can be used to closely align the combustion gas mixture through the porous refractory panel.

This sealing gas thus helps the combusted gaseous products to create an atmosphere with a very low oxygen content or with a strong reducing power, for example by having a significant hydrogen content.

FIG. 19 shows upper radiant heaters 9 phased together and held in fixed position by side blocks 906 of insulation.
02 and a downward radiant heater 904.

A wire mesh conveyor 908 is configured to slide through the interior of the furnace carrying the workpieces to be annealed or brazed.

The entrance of the furnace above the conveyor is a strip curtain 910
The inlet section below the conveyor is closed by a one-piece wall 912.

Heaters 902, 904 are operated in the manner described above.

The sealing gas flow indicated by arrow 920 can be used, for example, cracked ammonia, a propane/nitrogen mixture, or pure propane.

If such a sealing gas is used, it is preferable to adjust the combustion mixture so that little or no excess oxygen is produced for it.

The interior of the furnace thus becomes a highly effective reducing atmosphere that prevents oxidation of the workpiece and even acts to reduce any oxidation present in the workpiece when it is introduced into the furnace.

Moreover, despite the strong reducing atmosphere inside the furnace, the combustion of the combustion mixture takes place very effectively and provides radiant heat of at least red-hot temperatures.

Each of the Needlink '77 El engineered ceramic fiber panels described above is advantageously manufactured to very long dimensions, such as 25 feet or more.

Such panels are particularly suited for use in width-to-heat devices, and a construction of this type is shown in FIG.

In the configuration of FIG. 20, the side edges of the ceramic fiber panel 1010, which is about 15 feet long and about 1 foot wide,
The rectangular combustion mixture-filled chamber 1030 is brought into contact with the surface of the sealing air-filled chamber 1020 surrounding the combustion mixture-filled chamber 1030, and the side edge is attached to the chevron-shaped member 1.
040 and tightened with a screw 1050 with a shoulder 1052 against the top wall of the filling chamber 10209.

A panel 1010 that is not stiffened by a bonding agent or the like is
Under the influence of the pressure within the filling chamber 1030, it bulges out as shown at 1060.

Although this is not particularly disadvantageous and is in some respects desirable as it reduces heat radiation from the face of the panel to the clamping chevrons 1040, etc., this bulging phenomenon
This can be suppressed by applying preliminary tension to the panel when it is installed.

Another technique for stiffening a flexible panel is to form the panel by needling around a stiffening member, as shown in FIG. 21, for example.

That is, a wire mesh screen 1102 is inserted between two layers of ceramic fibers 1106 and 1110, and the two layers are intertwined in a felt-like manner by needling.

Although the present invention has been described above in connection with embodiments, the present invention is not limited to the structure and form of the embodiments illustrated herein, and may be modified in various ways without departing from the spirit and scope of the present invention. It should be understood that many different embodiments are possible and that various changes and modifications may be made.

[Brief explanation of drawings]

FIG. 1 is a front view of an infrared heating device according to the present invention, and FIG.
3 is a plan view of parts that may be used to construct the support frame of the heating device of FIGS. 1 and 2; FIG. Figure 4 shows the first
Figure 3 is a detailed view similar to the figure, but with the porous panel and upper frame member removed to show certain components suitable for the heating device of the present invention; FIG. 5 is a view similar to FIG. 2, illustrating another method of constructing the thermothermal device of the present invention. 6 is a sectional view of a heating device system according to the invention, FIG. 7 is a sectional view of an apparatus for carrying out the invention, FIG. 8 is a sectional view of another embodiment of the invention, and FIG. 10 is a plan view of the heating device assembly shown in FIG. 9; and FIG. 11 is a sectional view of a gas-fired radiant heating device according to the present invention; FIG. 11 is a plan view of the heating device assembly shown in FIG. 9; FIG. A sectional view of the heating device structure, FIG. 12 is a plan view of the heating device of FIG. 11, and FIG.
FIG. 14 is a plan view of a portion of the heating device showing ancillary equipment suitable for use with the present invention. 15 is a cross-sectional view of the device of FIG. 14 taken along line 15-15; FIG. 16 is a cross-sectional view of a heating device structure according to another embodiment of the invention; FIGS. Cross-sectional view of a heating device structure according to yet another embodiment of the invention, No. 19-2
FIG. 1 is a diagram of still another embodiment of the present invention. The main symbols in the figure are as follows. 10: Porous fireproof panel, 21-24: Upper frame member, 30: Lower frame member, 3L32: Tubular support member, 40: Rear plate, 53: Connection pipe, 55 Nislot,
56 Bitop wall, 64: Screw, 73: Flat support member (overhanging part), 81-85: Diagonal joint surface, 89: Joint part, 11
0: Table, 114 Niblock, 116: Passage, 12
4 Ni blower, 126: Suction pipe, 134: Support member, 1
36° 137: tube plate, 150: heater, 152: ceramic fiber mat, 156: face plate, 158 two cylindrical parts,
160: Hemispherical part, 162: Filling chamber, 164: Housing, 166: Partition plate, 171° 172 two-man unit, 199: Sealant, 200: Heating device, 202: Cup-shaped panel, 204: Support assembly, 210 : Full chamber, 21
2, 214: Angle member, 220: Side edge, 230: Outer filling chamber, 232 Nislot, 236, 238: Clamp angle member, 240: Screw, 251: Heating device assembly, 3
02: Filling chamber box, 304: Tubular filling chamber, 330 Nislot, 340: Fireproof matrix, 342: Tightening frame, 700: Heating device, 702: Roof-shaped retainer, 704: Clamp ring, 706: Support ring , 11
0: Edge portion, 712: Mountain portion, 720: Hat-shaped fireproof ceramic panel, 730: Filling chamber, 732: Entrance, 750
: Filling chamber, 760: Inlet, 800: Heat exchanger, 802:
Hollow interior, 804: Panel, 808: Mounting plate, 820:
Partition disk, 822: tubular support, 830: peripheral slot, 840: filling chamber, 850: filling chamber.

Claims (1)

[Scope of Claims] 1. In a gas-fired radiant heating device, a porous refractory mat made of felt-like refractory fibers suitable for passing a combustion gas mixture;
means forming a region and a second region to separately supply gas to corresponding regions of the mat; and means for supplying a combustible gas mixture such that, in use, the combustible gas mixture flows through the mat and combusts upon exiting the mat. and means for supplying non-combustible gas to the second region to prevent the combustion gas mixture in the first region of the mat from spreading through the mat into the second region. A gas-fired radiant heating device. 2. In the heating device according to claim 1,
When the heating device is in use, the gas from the second region flows around the mat from the first region, so that the second region prevents the gas from the first region from spreading to the edges of the mat. A heating device characterized in that the region is peripheral to the first region. 3. In the heating device according to claim 2,
A heating device characterized in that the refractory fiber is a ceramic fiber. 4% Any one of claims 1 to 3
A heating device according to claim 1, characterized in that the mat is attached to the frame at its edges. 5. In the heating device according to claim 4,
The frame has a depending flange that rests on the edge of the outer surface of the mat and holds the mat against an opening in a combustion gas mixture plenum chamber forming a first region within the heating device body; rests on the edge of the heating device body forming the second region, and the depending flange clamps the edge of the mat against the heating device body to reduce the thickness and porosity of the mat. 6. In the heating device according to claim 5,
A heating device characterized in that the horizontal flange is bolted to the heating device body by bolts passing through the edge of the tightened mat. 7 Any one of claims 4 to 6
The heating device according to item 1, wherein the outer surface of the frame is coated with a heat insulating material. 8. In the heating device according to claim 7,
A heating device characterized in that the insulating material is a thin layer of mineral felt. 9 Any one of claims 1 to 8
The heating device according to item 1, having a filling chamber box, characterized in that the means for forming the second region is a channel member fixed to the outside of the filling chamber box so as to form a tubular filling chamber. heating device. 10 In the heating device according to claim 9,
A heating device characterized in that a channel member is fixed to a filling chamber box by spot welding. 11. A heating device according to any one of claims 9 or 10, in which the channel members have flanges of unequal width, the wider flanges being on opposite sides of the mat, A heating device fixed to a surface, characterized in that narrow flanges with their free edges away from the plenum box form a slot-shaped outlet for the tube plenum. 12 In the method of assembling a gas combustion heating device, the second
a heating device body having a first plenum for a combustion gas mixture surrounded by a plenum and provided with an opening, a second plenum for the combustion gas mixture exiting the opening of the first plenum; molded a piece of porous felt-like ceramic fiber mat with an unsealed edge to cover the opening and a second plenum, with slots to release a narrow stream of unburned gas, and the molded mat Place it on the second filling chamber,
and securing the mat in place by its edges.