Abstract: Injection of gas into a bed of solids contained in a hopper is compartmentalized to allow independent control of gas to be vented upward and gas and solids to be discharged.

Abstract: A pressurized fluid is injected into a mass of material through at least one length of hose or other tubing of inherently resilient, elastomer material having one end closed and provided with at least one series of potential openings cut into the elastomer material along the length of the tubing so as to be normally tightly closed by reason of the resilency of the elastomer material but stretched open under the influneces of the pressurized fluid, which is introduced through the opposite end of the length of tubing. Gravity discharge of particulate material from a vessel having a hopper portion at its bottom can be effectively activated in this manner by the fluid-injection device of the invention.

Abstract: A pneumatic dosimeter for providing exact dosage of pulverulent materials, for instance for supplying aluminium oxide and fluoride to an aluminium electrolytic cell, comprises a vessel (1) with an upper chamber (2) which at the bottom is provided with a fluidizing device in the form of a fluidizing canvas (3) with an underlying chamber which is connected to an air source via a pipe line (5). The vessel is provided with an inlet (6) for the supply of pulverulent material from a supply tank or hopper (7) to the upper chamber (2), and an outlet opening for discharging the chamber (2). At least one fluidizing channel or pipe (9) is provided between the supply tank (7) and the vessel (1). This channel is provided with a fluidizing wall or fluidizing canvas (10) which is connected to an air supply source through a pipe line (12).

Abstract: A modularly constructed, trailerable, skid mounted, multi-compartmented concrete mixer and cement storage silo having a plurality of longitudinally aligned, bottom mounted, driven feed chains. In a combination construction, a single motor is cooperatively coupled to the feed chains of each mixer compartment and the feed chain of the cement silo to feed the cement/sand/aggregate in metered quantities to a turreted, separately powered auger where water is added and along the length of which the concrete is mixed. A silo vent column includes a plurality of fabric collection filters and means for vibrationally removing and reclaiming the cement. Air infiltration ports mounted along the bottom of the cement silo and one or more vibrators mounted to the mixer adjacent the sand and aggregate bins prevents crusting. Alternatively, the silo may be self-powered, and/or the mixer and silo may be transported independent of one another and/or without the trailer.

Abstract: A particulate solids transport bag with a gas assist unloading feature. The bag is one having an enclosing flexible side wall, or walls, flexible bottom wall provided with an opening, preferably a spout, and a gas distributor. The gas distributor is of tubular shape formed by a flexible material located atop or upon, around or surrounding said bottom wall opening, or spout, and contains a gas permeable upper face, gas impervious lower face and gas inlet into the tubular space. Gas, particularly air, is injected via the inlet into the tubular opening and passed through the gas permeable upper face of the flexible material to aerate and render the solids flowable for discharge through the opening, or spout, of the bottom wall.

Abstract: A bulk storage silo including a slanted floor opening into a discharge chute provided in the foundation of the silo wherein the floor is covered by a deck composed of a plurality of plates connected to vibrators arranged in a predetermined pattern which, when activated, causes the residual amount of grain which cannot be removed by gravity to flow into the discharge chute.

Abstract: A screw seal for conveying bulk particulate solids between spaces at differing gas pressures with minimal leakage of gas. A tubular housing encloses a screw conveyor section and a sealing section receiving the solids and forming a sealing plug. The sealing section has a divergent configuration that functions in combination with friction to create sufficient solids pressure with minimal driving torque and wear on the screw conveyor.

Abstract: A fluidation kit for retrofit installation on a pneumatic outlet for a railway covered hopper car is disclosed. The outlet includes an outlet pan having downwardly sloping walls. The kit includes at least one air permeable fluidizing membrane on the inside face of the outlet pan wall to fluidize a powdered or pulverant lading. An externally mounted manifold assembly is attached to outside surfaces of the outlet pan for connecting the air permeable fluidizing membranes on the inside surfaces of the downwardly sloping walls of the outlet pan to a source of fluidizing air. The air permeable fluidizing membrane is supported in a peripheral extending frame member which supports the air permeable fluidizing membranes a small predetermined distance above the sloping wall surfaces to provide a plenum therebetween for diffusing fluidizing air throughout the entire extent of the air permeable fluidizing membrane.

Abstract: An air blast generator is provided in the form of a pressure accumulator with a spring-loaded bellows. Air pressure expands the bellows, compressing the spring to store energy. When a valve is opened the spring aids in expulsion of the air such that a high pressure discharge of air is provided for a larger duration than would be possible without the spring.

Abstract: The present invention is directed to an apparatus and method for equalizing the flow rate of a combustible, particulate solids, such as coal, and gas mixture discharged from a feed vessel apparatus in a uniform manner to a pressurized receiving reactor, such as a gasifier.

Abstract: Apparatus and method for feeding particulate material from a hopper into a process stream at a controlled flow rate. A rotating wheel with spaced apart pockets is vibrated to densify the particulate material in the pockets. A stator contacts and covers a portion of the upper surface of the wheel and has a transfer station connected to discharge particular into the process stream. The wheel is driven in rotation at a controlled rate to control the particulate flow rate into the process stream. A conveying gas supply projects a jet of gas into the pockets for removing the particulate material and conveying it into the process stream. An aerating gas supply directs an upward flow of gas from the periphery of the wheel, through the particulate material being supplied to the wheel to fluidize the particulate material supplied to the wheel.

Abstract: A limp, porous membrane of sheet (i.e., cloth) material for a fluidized outlet is disclosed. The outlet is in communication with a container, such as a hopper within a covered hopper railway car, containing a supply of particulate material for being fluidized and unloaded via the outlet. The outlet comprises an outlet housing, an outlet frame for securing the outlet housing to the hopper, an outlet opening, and outlet walls extending from the frame to the outlet opening. The membrane is secured to the outlet frame and to the outlet opening and is disposed generally on the inside faces of the outlet walls. A manifold is provided for introducing a fluidizing fluid (e.g., air) under pressure between the outlet walls and the membrane such that the fluidizing fluid flows through the membrane thereby to fluidize the lading above the membrane.

Abstract: A blasting device for pulverizing material being fed through a hopper connected to a supply of pressurized gas. The blasting device comprises a housing member including an intake opening connected to the supply, an output opening connected to the inside of the hopper and a top opening. A tubular member connected to the output opening on one end are disposed within the housing member so that two compartments are defined. A cap member cooperatively and hermetically sealing the top opening thereby defining a third compartment. A diaphragm/valve member sandwiched between the peripheral underside of the cap member and the top opening of the housing, including a spring biased assembly urging the valve member downwardly in contact with the other end of the tubular member thereby separating the two compartments. Conduit means connecting the supply to the third compartment. Valve means for opening and closing the third compartment.

Abstract: An air distributor head mounted in a sloping wall for a hopper for pulverulent material to agitate and aerate the material as it travels down the wall surface toward the discharge opening in the bottom of the hopper; the head assembly including a generally cylindrical head with air flow passages and having an expandable generally cylindrical resilient skirt surrounding the body thus permitting air supplied through the passages under the skirt to be discharged into the pulverulent material to incorporate a flow of agitating and fluidizing air into the material.

Abstract: A feed valve for the quick discharge of an accumulator includes a piston with a small clearance relative to a cylinder. The piston has a rear face carrying a guide block which maintains the piston in proper position by cooperation with a slide. An elastic device, such as a spring, biases the piston to a closed position. The valve arrangement is especially useful for silo products such as granular or pulverulent products.

Abstract: Apparatus for controlling a flow of granular material wherein a first member has a first conical side wall and a second member has a second conical side wall arranged adjacent to the first conical side wall so that a passage is defined between the wall of the adjacent side walls, wherein at least the second conical side wall of the second member is provided with a device for introducing aeration agent into the passage.

Abstract: A powder product to be sprayed is conveyed by a stream of gas in a flexible conduit between a storage tank and a spray orifice from which a mixture of the gas and the product is ejected. The mixture is agitated upstream of and in the vicinity of this orifice by oscillating a section of the flexible conduit in the vicinity of this orifice. The powder product sprayer comprises a flexible conduit and a device for circulating a mixture of the product and the gas in this conduit. It further comprises an enclosure surrounding a section of the conduit and a device for oscillating this section of the conduit. The device for oscillating the conduit may comprise a vibrator fixed to this section of the conduit and free to move inside the enclosure. The vibrator may comprise an annular cage surrounding and fixed to this section of the conduit, a ball movable inside the cage and a device for injecting air into the cage in a direction adapted to cause movement of the ball inside the cage.

Abstract: The emptying device for a bulk silo (1) with flat or slightly inclined silo bottom (8) comprises an outer slope (2) and open air transport grooves (7) distributed over the silo bottom (8). The air driven conveying chutes (7) extend radially to a ventilated annular chamber (3) located inside the outer slope (2) of the silo bottom (8), the bottom of which annular chamber is provided with open air driven conveying chutes (4) and is inclined toward the discharge opening (5). The bottom of the annular chamber (3) is located lower than the silo bottom (8).

Abstract: A system for supplying a gas under pressure to a vessel such as a blender for particulate material which includes a central vertical lift column for recirculating material through the vessel to achieve blending. The system uses a first source of gas under pressure which may be a low pressure source suitable for a continuous operation of the blending apparatus. The system also is connected to a high pressure source of air such as plant air which is utilized as a supplemental source of air under pressure for initial start-up of the apparatus. A control system is provided which regulates the flow of the high pressure air to the gas supply conduit which acts as a reservoir for high pressure air. The control system allows the gas supply conduit to be pressurized.

Abstract: An apparatus and method is presented for emptying metallurgical vessels, and in particular steelmaking converters containing metal and slag, whereby the slag is effectively separated from the metal during pouring. The apparatus includes at least on permeable refractory element located near the flow hole. An agitating gas is fed through the refractory element thereby creating a bubbling froth which effectively obstructs most of the slag from being carried along by the vortex which forms above the vertical flow hole.

Abstract: A blowing device for the elimination of compactions in bulk material storage silos by using air blasts, includes a compressed air storage container, a compressed air supply duct, a compressed air outflow duct and an interposed rapid exit valve. The rapid exit valve has a conduit in which a valve closure is guided whereby the conduit turns into the compressed air supply duct forming an afflux cross-section for the valve piston over a miter cut or tube turn. The afflux cross-section is selected to be significantly greater than the outflow cross-section in the compressed air outflow duct. In this way, the flow losses, and pressure losses, otherwise customary are considerably reduced, so that extremely high flow velocities can be achieved in the compressed air outflow duct until the velocity of sound is reached. The result is a rapid impulse-like discharge of the compressed air storage container and, consequently, faultless elimination of possible compactions.

Abstract: A controllable valve adapted to be fixed in the wall of a storage hopper containing particulate materials and operable to dispense an air blast into the interiors of the hopper to loosen the materials in the region of the valve.

Abstract: An unloader for bulk materials is provided to transfer material such as cement from a barge or other bulk container. It includes a moveable and rotatable support member such as a crane or cantilevered arm that is adjacent the bulk container. A first conveyor or auger is connected to the support for pivotal movement and extends generally horizontally. A second conveyor or auger is connected to the distal end of the first conveyor for pivotal movement and is generally vertically oriented. A feeder unit is connected to the distal end of the second conveyor for universal and rotational movement. The feeder includes an uplift portion communicating with the second conveyor, the uplift portion advancing the bulk material at a rate slower than the second conveyor, and a collector portion communicating with the uplift portion. The collector portion includes converging auger assembly to advance the bulk material towards the uplift portion and to assist in transferring it into the uplift portion.

Abstract: A bag-filling machine, in which the material to be filled is conveyed by compressed air through a filling tube, has a storage cylinder which is closed at its underside by a grid-like floor having ventilation apertures. The filling tube is fitted above the floor in the peripheral wall of the storage cylinder. An improvement in the flow of the material to be filled and a more complete emptying on termination of the filling procedure are achieved if the floor is formed from at least three segments. Below the segments, sealed relative to one another, respective specifically associated compressed air supply chambers are disposed which are each provided with a regulatable compressed air supply.

Abstract: A screw powder feeder has a rotary screw (12) disposed at the base of a hopper (10). The screw (12) comprises a twist drill bit. Powder is discharged into a chamber (18) and picked-up by a flow of gas. The pressure in chamber (18) is varied relative to the pressure in hopper (10) to control the feed rate for a given screw speed. Ultra-low feed rates are made possible by feeding gas into the hopper (10) through the screw (12) and controlling the relative gas pressures such that the pressure in the chamber (18) exceeds the pressure in hopper (10).

Abstract: An air cannon which includes a pressure tank with an inlet opening and an outlet opening for air, whereby the outlet opening is composed of a tube which is airtightly fastened in the wall of the pressure tank and the one open end terminates inside the pressure tank and the other open end extends out of the pressure tank. A cylindrical shaped second tube is fixed in the pressure tank with an open end and a closed end, generally concentric to the mentioned first tube, of which the cross section is larger than the cross section of the first tube. The first tube extends through the open end into the inside of the second tube, and is generally concentric to it. In the bottom of the second tube there is provided an in and outlet opening for the in and outflow of air.

Abstract: There is disclosed a flexible, hollow, tubular member for conducting a fluid therethrough to cause the tubular member to move in a whip-like manner inside a container. The conduction of fluid therethrough causes the tubular member to move in a generally upward direction through material in the container while producing whip-like motions of the tubular member to agitate compacted portions of the material and cause the material to discharge from the container. The container may include a passageway covered by an entry/sealing means which includes a one way flap or a flexible tubular housing to permit insertion of the tubular member enclosed by a tubular housing into the container, while preventing the escape of material from the container when the tubular member/housing has been removed. Retraction of the tubular housing relative to the flexible tubular member providing a substantially exposed section of the tubular member to allow for the random, whip-like movement of the tubular member in the container.

Abstract: Device and process for introducing a powder with catalytic activity into a fluidized bed polymerization reactor (1), the said device comprising:a storage enclosure (2) for powder with catalytic activity, provided with a feed line (3) for powder with catalytic activity and a shut-off valve (26), this enclosure being connected to a metering device (4) making it possible to deliver periodically a given volume of powder with catalytic activity,an intermediate chamber (5), placed below the metering device to receive direct the powder delivered by the latter, this intermediate chamber comprising in its upper part a tube (6) bringing in a inert carrier gas, provided with a shut-off valve,piping for conveying the powder (8) connecting the bottom part of the intermediate chamber to the fluidized-bed reactor, this piping having a portion which is more or less horizontal, the said powder conveying piping being provided with a full-bore rapid-opening valve (10).

Abstract: Improved sieving apparatus for size analysis of dry powder having a sample chamber floored by a sieving screen and an underlying fines chamber adapted to be mated in fluid communication therewith. Disposed beneath the screen is a jet emitting rotor of selective configuration adapted to emit an upwardly directed air jet curtain to repeatedly sweep the underside of the screen to both improve the screening action and to reduce the required time therefore.

Abstract: A quick release aerator is provided for discharging intermittent bursts of pressurized air into a storage container to implement material flow. The unit includes a piston and valve assembly disposed internal to a pressure tank. The assembly features one or more vent ports defined through the sidewalls of a cylinder to allow the passage of pressurized air from the tank to an outlet orifice. The total area of the vent ports equals or exceeds the area of the exhaust port, thereby maximizing the effect of the burst of pressurized air.

Abstract: An aeration device is disclosed for assisting discharge of material from containers. The device comprises a resilient flexible skirt member which has an inner conical surface and an outer conical surface. An anchor stud is disclosed for fastening the skirt member in the prestressed condition with the stud secured to a cup-shaped housing on an exterior of the container. A gas conduit connects an interior of the cup member and the pressure chamber with a source of a pressurized gas.

Abstract: The present invention provides a new wetting chamber for a metering and wetting system typically for polyelectrolyte polymer. Atmospheric air is used to disperse the polymer fed into the chamber by a suitable feeder and to generate air/water turbulence in the wetting chamber in which the polymer is wetted. Suction draws the metered polymer into the wetting chamber and increases the downward velocity of the polymer as it enters the turbulent section of the wetting chamber. When wetted, the polymer is transferred to a mixing tank for aging. It is then ready for use in various industries.

Abstract: A system for supplying a slurry includes a hopper having a lower portion tapering to an outlet at its lower end. A liquid is supplied to the hopper interior along a wall of the lower portion in a direction having a horizontal component. Particulate material feeding from a main portion of the hopper into the lower portion becomes entrained in the liquid, thus forming the slurry.

Abstract: An improved feed screw impeller apparatus primarily for use in an impeller bag packing system that is especially suited for filling bags with finely divided and aerated powders. The apparatus comprises an elongated cylindrical shaft having impeller blades extending radially therefrom at about the midpoint thereof and a plurality of feed screw flights of generally helical configuration, at least two such flights connected to said shaft on each side of the impeller blades in substantial coaxial alignment with the shaft. In one alternative embodiment of the invention there are four impeller blades and four helical feed screw flights, two on each side of the impeller blades and each terminating along an edge extending in substantial alignment with a different impeller blade. Another version of the novel impeller is employed in a packing machine also having a novel pre-conditioning hopper.

Abstract: Activator for fluidizing slow-moving material in fluid containers (10). The activator comprises a flat activator hose (15) which is suspended on a support member (16) arranged like a coat-hanger, a conduit (17) projecting into the activator hose between the layers thereof for the supply of pressurized gas pulses to the space between the front and rear layers of the activator hose. At least the front layer of the activator hose is gas-permeable and allows transmission of the pressurized gas pulses to the material in the container, a rhythmical movement simultaneously being imparted to the front layer in relation to the rear layer in pace with the pressurized gas pulses.

Abstract: A storage container for solid particulate materials includes a source of `lubrication` gas coupled to a fluidizer. The fluidizer particulate materials are carried from the container by a stream of transport gas. A deflector placed over the container outlet constrains the fluid flow in a substantially horizontal path to prevent the outlet becoming blocked by the solids when the gas flow is cut off. The proportions of particulate material can be varied by selectively varying the pressure in the container, where the container is a pressure vessel.

Abstract: Apparatus for attachment to the side wall of a hopper or bin, having connections to an extenal source of pressurized air, and having an annular orifice internal to the hopper or bin, wherein the annular orifice is covered by a resilient ring, thereby pemitting the flow of pressurized air outwardly through the annular orifice while protecting the annular orifice from contamination and plugging by materials stored in the bin or hopper.

Abstract: Mixing silo for pneumatically homogenizing fine-grained or dust-like material, the bottom of which comprises groups of aeration zones which can be alternately supplied with compressed air in such a manner that in each group a bottom zone partially limited by the outer limit of the silo bottom is heavily aerated and a bottom zone located between the heavily aerated bottom zones is aerated only weakly. An even, progressive circulation of the entire silo contents with little expenditure of energy is achieved by separating the heavily aeratable bottom zones from each other with a star-shaped, exclusively weakly aeratable bottom zone and by constructing the outlet as an overflow.

Abstract: A combined storage silo and homogenizing device for powdery materials such as cement raw meal. A silo is divided into an upper storage vessel and a lower homogenizing chamber. The storage silo has a slab floor having a plurality of spaced apart openings therein which serve as outlets for the vessel and communicate with inlets for the homogenizing chamber. The homogenizing chamber includes a small pneumatic blending device having a lateral outlet in its bottom feeding blended material to a column having a top outlet for the device.

Abstract: A multiple blast aerator hopper system for handling bulk material. A plurality of blast aerators are fitted at radially spaced-apart intervals about the periphery of the hopper; the first blast aerator is positioned near the bin outlet, and each succeeding aerator is usually vertically elevated thereabove. The blast aerators are periodically fired in a timed, rotary sequence starting with the first, lowermost aerator and continuing serially with higher, radially spaced-apart aerators. Preferably each aerator includes an internal valve seat assembly which houses a resilient, dual diameter piston for axial movement between the sealing position and a rearward, aerator fill position. An external solenoid valve controls each aerator. Preferably the blast discharges of each aerator are directed downwardly, tangentially with respect to the walls of the bin or hopper on which the system is mounted.

Abstract: Particulate blending apparatus including a vessel, the lower end of which is a downwardly tapered funnel-like section. A vertical divider divides the tapered section into first and second compartments. A vertical tubular member is centrally disposed in the vessel so that the lower end thereof provides an inlet into the vessel and the upper end opens into the upper portion of the vessel. First and second openings are provided on opposite sides of the vertical tubular member at the lower end thereof through which particulate materials may flow by gravity into the tubular member from the first and second compartments, respectively, of the tapered section. A blower may be connected to the lower end of the tubular member providing a stream of air therethrough by which particulate materials entering the tubular member through the first and second openings may be entrained therewith exiting through the upper end of the tubular member for redeposition in the vessel.

Abstract: The invention relates to a continuous mixing silo and a method of operating it for the mixing of fine-grained material. The silo has a base provided with a plurality of zones which are supplied with aerating air in chronological sequence. Individual zones of the base are supplied with additional air in a pulse-like manner at specific intervals of time to achieve intensive aeration and mixing of the material. The additional air is supplied from a storage unit for a shorter period than the aerating air. Air taken from the storage unit is replenished during the time interval between pulses.

Abstract: A process for mixing materials in bulk comprises the continuous and simultaneous withdrawal, through discharge openings distributed about the periphery of a mixing silo, of the material in such a manner that the vertical velocity of the descending material increases progressively about the periphery of the silo. Apparatus in accordance with the invention comprises a mixing silo having a relatively large number of discharge openings and means for insuring that the velocity differences in the material being withdrawn through adjacent openings is relatively small whereby the variation in material vertical velocity from the lowest to the miximum value will occur over a large number of discharge openings.

Abstract: A blast aerator for dislodging bulk materials in storage hoppers or the like. The blast aerator preferably comprises a rigid, generally cylindrical tank with a blast discharge opening coaxially aligned with its axis. A blast discharge assembly coupled to the discharge opening includes an elongated, one-piece, rigid discharge pipe of a predetermined internal diameter. A valve seat assembly is coaxially secured against an internal shoulder of the pipe. A resilient dual diameter piston is disposed within an intermediate portion of the pipe for axial movement between a sealing position wherein its reduced diameter portion abuts the valve seat assembly and a rearward, aerator fill position. The larger diameter portion of the piston axially tracks within the intermediate diameter portion of the discharge pipe. A valve cap assembly is coaxially secured at the end of the discharge pipe internally of the tank, defining a cavity between it and the piston rear.

Abstract: A control arrangement is provided to control discharges of compressed gas to vessels containing difficult to unload material comprising one or more control valves connected in operative relation to discharge valves operative to discharge compressed gas from an accumulator. The control valves are provided with a time control circuit for controlling the time of discharge of compressed gas from the accumulator(s). This time control circuit may comprise a pneumatic, electro-mechanism and/or electronic timers. The control arrangement may also include an arrangement for applying pressure gas to discharge valves which are in operative relation with accumulator discharge devices which are not being utilized for unloading. Various arrangements for mounting the accumulators, discharge valves, conduits, and discharge devices are illustrated in connection with a railway hopper car. Certain discharge devices mounting arrangements are preferred in unloading certain types of lading.

Abstract: A blast aerator for fluidizing granular material, comprising a container connected to a supply of compressed air, an aerator valve casing having a diaphragm chamber therein, a flexible resilient diaphragm dividing the chamber into first and second portions, a conduit connected between the container and the first portion, an air blast outlet connected to an outlet port in the first portion, the diaphragm including a valve member initially closing the port by the resilience of the diaphragm, a bleed opening in the diaphragm for pressurizing the second portion when the first portion is pressurized, and a control valve for opening and closing a vent outlet from the second portion, the control valve when closed allowing pressurization of the second portion, and, when open, exhausting the pressure therefrom, whereupon the pressure in the first portion opens the valve member and quickly releases the compressed air from the container to produce an air blast through the outlet.

Abstract: A fluidized bed heat exchanger in which a perforated plate is disposed within a housing for supporting a bed of particulate material which is introduced into the housing through an inlet. Air is passed through the plate to fluidize the particulate material and a drain pipe is provided for discharging the spent material from the bed. The flow rate of air introduced into the bed is increased in a direction across said bed from said inlet to said drain pipe to promote the circulation of the bed materials from the inlet to the drain pipe.

Abstract: Containers for receiving solid particulate product and for fluidizing and dispensing said product under the influence of a pressurized air flow. The present containers comprise a product compartment having a substantially vertical interior wall of air-permeable fabric, structure for supporting said vertical interior wall closely spaced from the exterior, vertical shell or wall of the container to provide an interconnecting narrow air space therebetween around the entire inner periphery of said shell, and structure for introducing pressurized air into said air space and through the air-permeable interior wall to fluidize substantially all of said particulate product which is in contact with said substantially vertical, air-permeable fabric inner wall.

Abstract: A method and apparatus are disclosed for controlling the density of dispensed hot melt thermoplastic adhesive foam in order to assure uniform foam characteristics. In order to create the hot melt adhesive foam, air or any relatively inert gas is mixed with the thermoplastic adhesive while the adhesive is in the molten state, and the mixture is then pressurized so as to force the gas into solution with the molten adhesive. As the molten adhesive/gas solution is dispensed at atmospheric pressure, the gas is released from solution and becomes entrapped in the adhesive so as to form a homogenous closed cellular adhesive foam. According to the practice of this invention, the supply of gas is periodically discontinued so as to prevent an excess volume of gas from being admixed with the molten adhesive whenever foamed adhesive is not being dispensed, thereby stabilizing the density of the adhesive foam.

Abstract: An aeroslide (50) includes a molded plastic base (52) comprising a bottom wall (54), side walls (56) extending upwardly from the bottom wall and end walls (58) extending upwardly from the bottom wall and joining the side walls to enclose the interior of the base. Indentations (66) are formed in the upper portions of the side walls, and reinforcing members (68) are adhesively secured in the indentations at spaced points along the length of the base. Flanges (60) extend outwardly from the upper ends of the side walls and the end walls, and a porous fabric layer (70) is secured in place over the open top of the base by an adhesive layer extending between the upper surface of the flanges and the adjacent undersurface of the fabric layer.