Dampfgenerator

Abstract

Steam generator, comprising at least a cylindrical combustion chamber made of metallic materials and at least a second cylindrical component made of a metallic material, which has a larger inner diameter than the outer diameter of the cylindrical combustion chamber and a shorter length of the lateral surface between the base surfaces than the cylindrical combustion chamber, and the cylindrical combustion chamber thereby projecting beyond the base surface of the cylindrical component on at least one side, and wherein the cylindrical combustion chamber is arranged within the second cylindrical component with its central axis eccentric to the central axis of the second cylindrical component, and further comprising an opening in a base surface of the cylindrical combustion chamber for introducing fuel, which can be closed by a metallic door.wherein the metallic door and / or the base of the combustion chamber with the opening are in turn provided with at least one further closable opening for the realization of bottom and top air for the combustion chamber, and furthermore the base of the combustion chamber opposite the base with the opening is provided with an opening for a flue pipe with a damper, and furthermore the second cylindrical component is provided in the lower area with a closable drain and / or a closable discharge opening, and furthermore the second cylindrical component has a closable inlet with a non-return valve in the area below the maximum filling level, and furthermore at least one U-shaped metallic siphon is present,which has an opening in the upper inner area of ​​the second cylindrical component and is led from there into the cylindrical combustion chamber over its remaining length and from there through an opening in the upper area of ​​the cylindrical combustion chamber, which in any case is located outside the cylindrical component, and where the opening of the siphon is provided with a distributor, the siphon being provided with a metallic lining in the area of ​​the combustion chamber, and furthermore a weight-loaded pressure relief valve is present in the upper area of ​​the second cylindrical component.

Description

[0001] The present invention relates to the fields of energy technology and mechanical engineering and concerns a steam generator, such as can be used, for example, in the food industry, in equipment manufacturing for the sterilization of devices or in beekeeping as a device for melting the wax of beehive components.

[0002] A steam generator for low-pressure steam heating systems is known according to DE 10325 A, which consists of a system of fire bodies of the device described in more detail in any number, which communicate with each other through channels located in them, wherein, advantageously, without the provision of a water space, the water to be evaporated is continuously injected according to consumption, and wherein, advantageously, the steam formed is dried and superheated by flowing through several of the fire bodies.

[0003] Also known is a transportable steam generator according to AT 263040, especially for agriculture and horticulture, which consists of a vertical fire-tube boiler with combustion chamber and vertical smoke tubes, above which a superheater is arranged, wherein the fire-tube boiler is surrounded at a distance and forming an annular space through which the combustion gases flow by a water jacket connected to the fire-tube boiler via a pipe, wherein the water jacket is designed as a removable bell and can be removed from the fire-tube boiler, which forms a unit with the superheater, after the connecting pipe has been disconnected.

[0004] Also known according to EP 3 701 797 B1 is a furnace with a steam generator, wherein the furnace includes an anti-limestone system configured to prevent the deposition of limestone on at least one section of the heating element, wherein the section of the heating element is inclined with respect to a horizontal plane when the furnace is in an operating state, and wherein the steam generator includes a gas flow collector adapted to direct a gas flow heated by the gas burner to the tubes of the heat exchanger, wherein the tubes project from an upper surface of the gas flow collector, and wherein the at least one section of the heating element inclined with respect to a horizontal plane comprises the upper surface of the gas flow collector.

[0005] Steam generators are also known for beekeeping, used for melting wax and sterilizing the internal components of beehives.

[0006] Bienen Ruck GmbH (bienen-ruck.de), a beekeeping supply company, offers a powerful and self-contained wood-fired steam generator with a 23-liter water tank, designed for independent and efficient wax melting using wood, without the need for electricity. The steam generator / wood vaporizer can be used both to generate steam and to heat water as an instantaneous water heater.

[0007] A combustion chamber measuring 30 x 25 x 50 cm (W x H x D), with a door opening of 27 x 19.5 cm and an interior of 50.5 x 30.5 x 37.5 cm, generates the steam. Pressure relief valves are fitted.

[0008] Bienenwagner.de also offers a steam generator for beekeeping, designed for steam wax melting and sterilization (Bienenwagner.de). This electric steam wax melter and sterilization unit has a power output of 2.2 kW and operates at 230 V, featuring a robust construction for efficient and safe operation. The steam generator can operate continuously and is equipped with overheat protection and pressure relief valves.

[0009] A disadvantage of the known solutions is that there is no simple solution for a steam generator with a combustion chamber that has a simple design and simultaneously meets all safety requirements.

[0010] The object of the present invention is to provide a steam generator which has a simple design and meets all safety requirements, does not require an electrical energy supply, and can operate autonomously and generate steam.

[0011] The problem is solved by the invention specified in the claims. Advantageous embodiments are the subject of the dependent claims, and the invention also includes combinations of the individual claims in the sense of an AND conjunction, as long as they are not mutually exclusive.

[0012] With the present invention, it is for the first time possible to specify a steam generator that has a simple design and meets all safety requirements, does not require an electrical energy supply, and can operate autonomously and generate steam.

[0013] The steam generator according to the invention comprises at least a cylindrical combustion chamber made of metallic materials and at least a second cylindrical component made of a metallic material, which has a larger inner diameter than the outer diameter of the cylindrical combustion chamber and a shorter length of the lateral surface between the base surfaces than the cylindrical combustion chamber, and the cylindrical combustion chamber thereby projects beyond the base surface of the cylindrical component on at least one side, and wherein the cylindrical combustion chamber is arranged within the second cylindrical component with its central axis eccentric to the central axis of the second cylindrical component, and furthermore comprises an opening in a base surface of the cylindrical combustion chamber for introducing fuel, which can be closed by a metallic door.wherein the metallic door and / or the base of the combustion chamber with the opening are in turn provided with at least one further closable opening for the realization of bottom and top air for the combustion chamber, and furthermore the base of the combustion chamber opposite the base with the opening is provided with an opening for a flue pipe with a damper, and furthermore the second cylindrical component is provided in the lower area with a closable drain and / or a closable discharge opening, and furthermore the second cylindrical component has a closable inlet with a non-return valve in the area below the maximum filling level, and furthermore at least one U-shaped metallic siphon is present,which has an opening in the upper inner area of ​​the second cylindrical component and is led from there into the cylindrical combustion chamber over its remaining length and from there through an opening in the upper area of ​​the cylindrical combustion chamber, which in any case is located outside the cylindrical component, and where the opening of the siphon is provided with a distributor, the siphon being provided with a metallic lining in the area of ​​the combustion chamber, and furthermore a weight-loaded pressure relief valve is present in the upper area of ​​the second cylindrical component.

[0014] Advantageously, the shapes of the base surfaces of the cylindrical firebox and the second cylindrical component are oval, elliptical, egg-shaped, triangular, almost round, round.

[0015] Furthermore, it is advantageous that rib-shaped metal parts are present on the outer surface of the cylindrical combustion chamber, at least partially extending around the circumference of the cylinder.

[0016] It is also advantageous to use steel or cast iron as the metallic material for the cylindrical combustion chamber and / or the rib-shaped parts, and steel or stainless steel as the metallic material for the second cylindrical component.

[0017] And, advantageously, the second cylindrical component is insulated on its outside.

[0018] It is also advantageous if the rib-shaped metal parts are guided around half the upper circumference of the cylindrical firebox and if, advantageously, between 2 and 20 rib-shaped metal parts are present.

[0019] It is also advantageous if the inner diameter of the second cylindrical component is 10 to 100%, preferably 20 to 50%, larger than the outer diameter with the rib-shaped metal parts of the cylindrical combustion chamber and / or the total length of the cylindrical combustion chamber is 10 to 50% longer than the total length of the second cylindrical component.

[0020] Furthermore, it is advantageous if the closable openings for realizing bottom and top air for the combustion chamber can be opened and closed simultaneously by means of a rotary slide.

[0021] It is also advantageous if pressure gauges, temperature gauges and / or a liquid level gauge are each arranged in the middle and / or upper area of ​​the second cylindrical component.

[0022] It is also advantageous if one or more devices for conveying steam are present from the distributor at the second opening of the siphon outside the cylindrical combustion chamber.

[0023] It is also advantageous if the steam generator is mounted on a frame which has at least two wheels below the steam generator and handles in the upper area of ​​the outer shell of the second cylindrical component.

[0024] It is also advantageous if filling with liquid can be carried out without pressure using a funnel via the nozzle of the weight-loaded pressure relief valve.

[0025] In the solution according to the invention, at least one cylindrical combustion chamber made of metallic materials and at least one second cylindrical component made of a metallic material are present.

[0026] Both cylindrical elements are arranged as horizontal cylinders in the steam generator according to the invention.

[0027] A cylinder is a geometric body in which two parallel, flat, congruent, usually circular bases are connected by a lateral surface (Wikipedia, keyword cylinder).

[0028] Advantageously, rib-shaped metal parts can be arranged on the outer surface of the cylindrical combustion chamber, at least partially around the cylinder's circumference. These rib-shaped metal parts can increase the energy transfer from the combustion chamber to the liquid inside the second cylindrical component.

[0029] A rib, technically, is a reinforcement that is attached perpendicularly to a component to increase its stability and reduce deformations (Wikipedia, keyword rib technical).

[0030] According to the present invention, the two cylindrical components each have two base surfaces and one lateral surface.

[0031] The shapes of the base surfaces of the cylindrical firebox and the second cylindrical component can advantageously be oval, elliptical, egg-shaped, triangular, nearly round, or round.

[0032] Advantageously, the cylindrical combustion chamber and / or the rib-shaped parts are made of metallic material, steel, cast iron, and the second cylindrical component is made of metallic material, steel, stainless steel.

[0033] It is also advantageous that the outside of the second cylindrical component can be insulated, for example by means of quilted mineral wool.

[0034] It is also advantageous if the rib-shaped metal parts are guided around half the upper circumference of the cylindrical firebox and, even more advantageously, between 2 and 20 rib-shaped metal parts are present.

[0035] The rib-shaped metal parts should be attached, in particular, to the upper circumference of the cylindrical combustion chamber, which points towards the larger internal volume of the second cylindrical component. Since the cylindrical combustion chamber is not located centrally within the second cylindrical component, the internal volume of the second cylindrical component is always unevenly distributed relative to the outer circumference of the cylindrical combustion chamber.

[0036] Furthermore, the second cylindrical component has a larger inner diameter than the outer diameter of the cylindrical combustion chamber with the rib-shaped metal parts and a shorter length of the lateral surface between the base surfaces than the cylindrical combustion chamber, whereby the cylindrical combustion chamber projects beyond the base surface of the cylindrical component on at least one, and preferably both, sides.

[0037] Advantageously, the inner diameter of the second cylindrical component is 10 to 100%, or even more advantageously 20 to 50%, larger than the outer diameter with the rib-shaped metal parts of the cylindrical combustion chamber, and / or the total length of the cylindrical combustion chamber is 10 to 50% longer than the total length of the second cylindrical component.

[0038] It is further important according to the invention that the cylindrical combustion chamber within the second cylindrical component is arranged with its central axis off-center to the central axis of the second cylindrical component, preferably so far off-center and deeper that it is located in the lowest region of the second cylindrical component.

[0039] The central axis of a cylinder is the straight line that passes through the centers of the two bases (Wikipedia, keyword central axis of a cylinder).

[0040] According to the invention, it is important that the cylindrical combustion chamber is arranged off-center in the interior of the second cylindrical component and is completely surrounded by liquid around its outer surface located in the second cylindrical component. Advantageously, the rib-shaped metal parts on the outer circumference of the cylindrical combustion chamber, if present, are also surrounded by liquid.

[0041] According to the invention, one base surface of the cylindrical combustion chamber has an opening for introducing fuel, which can be closed by a metal door. Grates for the fuel and / or an ash pan can be arranged inside the combustion chamber. Ash or other combustion residues can also be removed from the cylindrical combustion chamber through the door.

[0042] The metallic door and / or the base of the cylindrical firebox in which the door is located are, according to the invention, provided with at least two closable openings for the realization of bottom and top air for the firebox.

[0043] Advantageously, at least one further closable opening for the realization of bottom and top air for the combustion chamber can be opened and closed simultaneously by means of a rotary slide.

[0044] It is also advantageous for the metallic door to have at least a partial pane of fire-resistant glass to allow a view into the firebox.

[0045] According to the invention, the base of the combustion chamber opposite the base with the door opening is further provided with an opening to which a flue pipe with a damper is attached. The combustion power in the combustion chamber can be controlled by moving the damper.

[0046] It is further according to the invention that the second cylindrical component is provided in the lower area with a closable outlet and / or a closable discharge opening and furthermore the second cylindrical component has a closable inlet with a check valve in the area below the maximum filling height.

[0047] The fill level refers to the liquid to be vaporized in the steam generator, preferably water. The check valve prevents the escape of pressurized hot water during the filling process.

[0048] The drain is designed for the complete emptying of the interior of the second cylindrical component of the liquid, preferably water. The discharge opening can be used for any other residues that need to be removed from the interior of the second cylindrical component.

[0049] Of particular importance according to the invention is the presence of a u-shaped metallic culvert.

[0050] A siphon is a pressure pipe used to cross under a road, tunnel, river, railway tracks, etc. In the siphon, the fluid can overcome the obstacle without the need for pumps. This utilizes the principle of communicating vessels, known since antiquity, according to which stationary fluids in interconnected pipes always equalize to the same level (Wikipedia, keyword "siphon").

[0051] According to the invention, one opening of the siphon is arranged in the upper inner region of the second cylindrical component. From there, it is guided through an opening in the upper region of the cylindrical combustion chamber into the cylindrical combustion chamber and along its entire remaining length. From there, the siphon is guided through an opening in the upper region of the cylindrical combustion chamber, which in any case is located outside the cylindrical component. The second opening of the siphon is provided with a distributor to which devices for conveying the steam can be connected. Furthermore, it is advantageous that a temperature and / or pressure measuring device can be located in the region of the second opening in the cylindrical combustion chamber for the siphon, outside the cylindrical component.

[0052] Furthermore according to the invention, the siphon in the area of ​​the combustion chamber is provided with a metallic lining, advantageously laterally and in particular on the front side in the direction of the base of the cylindrical combustion chamber with the door, in order to avoid direct contact of the siphon with fresh air and to guide the hot exhaust gases of the combustion chamber along the part of the siphon located in the combustion chamber.

[0053] And according to the invention, a weight-loaded pressure relief valve is also provided in the upper area of ​​the second cylindrical component.

[0054] Advantageously, pressure gauges, temperature gauges and / or a liquid level gauge, such as a sight glass, can be arranged in the middle and / or upper area of ​​the second cylindrical component on the steam generator according to the invention.

[0055] It is also advantageous if one or more devices for conveying steam are present at the second opening of the siphon outside the cylindrical combustion chamber, the outlet openings of which preferably point downwards.

[0056] It is also advantageous if the steam generator is arranged on a frame which has at least two wheels below the steam generator and, even more advantageously, extendable handles in the upper area of ​​the outer shell of the second cylindrical component.

[0057] For transporting the entire steam generator, eyelets or sleeves for fastenings may be provided on the steam generator.

[0058] With the solution according to the invention, it is possible to continuously and also discontinuously supply steam, and in particular superheated steam, in a power range of 8 to 12 m 3 to generate / h.

[0059] The operating principle of the steam generator according to the invention is as follows.

[0060] Water is introduced into the second cylindrical component via a closable inlet with a check valve, located below the maximum fill level of the second cylindrical component, until the desired fill level is reached, as indicated by the liquid level gauge. Thus, the second cylindrical component is filled with water to such an extent that at least the outer circumference of the cylindrical combustion chamber (firebox), and advantageously also any ribbed metal parts, are completely surrounded by water.

[0061] A wood fire is then lit in the cylindrical firebox, and wood is added and the combustion is controlled via the closable openings in the base of the cylindrical firebox by regulating the upper and lower air through the door until the water inside the second cylindrical component begins to boil and form steam.

[0062] The efficiency of combustion can also be controlled by operating the throttle valve in the flue pipe, which is located in the base of the cylindrical combustion chamber opposite the base with the door.

[0063] The heating of the water can be indicated by pressure gauges and / or temperature gauges that have their sensors located inside the second cylindrical component.

[0064] After steam has accumulated in the upper part of the interior of the second cylindrical component and filled the available volume, it enters, for example, the first vertical leg of the siphon and is further heated by the combustion chamber as it flows through, for example, a horizontal section of the siphon. The superheated steam then exits, for example, through the second vertical leg of the siphon and can be extracted via the distributor and one or more steam distribution devices.

[0065] The process can be operated continuously or discontinuously. If steam is generated but not extracted, it is safely removed from the component via the weight-loaded pressure relief valve located in the upper section of the second cylindrical component. The amount of steam and the resulting pressure within the second cylindrical component can also be measured using a pressure gauge with its sensor positioned in the upper section of the second cylindrical component.

[0066] When steam is no longer needed, the firing can be stopped, the ash removed from the combustion chamber, and the remaining water removed from the second cylindrical component via the closable drain in the lower part of the second cylindrical component.

[0067] The steam generator according to the invention can be moved by one person using a frame with wheels and handles. For example, a beekeeper can move the steam generator according to the invention to the beehives, located, for example, in the forest, generate steam there with the steam generator and, for example, remove the wax from the frames in the beehives without needing an electrical connection and can be operated with renewable fossil fuels.

[0068] The invention will now be explained in more detail using an exemplary embodiment.

[0069] This shows Fig. 1 a steam generator according to the invention in perspective view and Fig. 2 a steam generator according to the invention in front and left and right side view Example 1

[0070] A cylindrical firebox made of sheet steel with round bases, a diameter of 30 cm, and a shell length of 70 cm is located inside a second cylindrical component with round bases, a diameter of 60 cm, and a shell length of 60 cm. This second cylindrical component is also made of sheet steel, with its outer shell insulated with quilted mineral wool and encased in aluminum sheeting.

[0071] The cylindrical firebox protrudes 3 cm at the front and 7 cm at the rear from the base surfaces of the second cylindrical component and is firmly welded to the base surfaces of the second cylindrical component.

[0072] On the outer surface of the cylindrical firebox are 20 rib-shaped metal parts made of steel, which are welded onto the surface transversely to its length and only cover the upper half of the outer surface of the cylindrical firebox.

[0073] One side of the firebox has a round opening 30 cm in diameter, closed by a sheet steel door. The door features a semicircular opening and a round opening 6 cm in diameter, through which the supply of top and bottom air to the combustion chamber can be controlled. A rotary damper is located in front of the two openings, allowing them to be fully or partially closed, or just one of them.

[0074] In the base of the second cylindrical component, which is located opposite the base in which the door is arranged in the base of the cylindrical firebox, a smoke extraction pipe is arranged in the upper area of ​​the base, from which the smoke from the firebox can be controlled and directed away via a throttle valve.

[0075] Furthermore, above the cylindrical combustion chamber in the base of the second cylindrical component, there is a sight glass for determining the liquid level in the second cylindrical component.

[0076] Halfway up the base of the second cylindrical component, a lockable tap with a check valve serves as an inlet. Water is introduced into the interior of the second cylindrical component through this tap.

[0077] 45 liters of water are added.

[0078] In continuous operation, water is replenished as needed during the ongoing process.

[0079] Furthermore, a U-shaped stainless steel siphon with a diameter of 5 cm and a wall thickness of 0.5 cm is present. It has an opening in the upper part of the interior of the second cylindrical component, and is guided by a bend through an opening in the upper part of the cylindrical combustion chamber into the combustion chamber and to the end of the combustion chamber. There, it is guided by another bend through an opening in the upper part of the cylindrical combustion chamber, the portion of which is always located outside the second cylindrical component. This opening of the siphon is equipped with two connections for steam lines. The siphon is welded into the openings of the cylindrical combustion chamber.

[0080] The culvert in the firebox is surrounded by a metallic cladding made of sheet steel with dimensions (LxWxH) 50x12x10 cm.

[0081] In the upper part of the second cylindrical component, there is a weight-loaded pressure relief valve which releases the steam from the interior when the pressure exceeds 0.5 bar.

[0082] The firebox is then loaded with wood, the fire is lit, and fuel is fed. Once the water inside the second cylindrical component boils and steam accumulates in the upper part of this component, the steam, when the upper volume is full, enters the opening of the siphon and is guided through the siphon, where it is further heated by the combustion chamber.

[0083] At the distributor, the steam is present at a temperature of 110 to 140 °C and a pressure of 0.2 to 0.5 bar and can be conveyed via hoses for use.

[0084] Additional pressure measuring devices can be arranged with their sensors in the upper area of ​​the interior of the second cylindrical component and in the siphon in front of the distributor.

[0085] Once steam generation has ceased and the fire has gone out, the ash can be removed and any remaining water drained through the drain valve in the lower part of the second cylindrical component. Reference symbol list 1 steam generator 2 cylindrical combustion chambers 3 second cylindrical component 4 Openings in the base of the cylindrical firebox 5 Flue pipe 6. Exit or discharge opening 7 Inflow 8 culverts 9 distributors 10 weight-loaded pressure relief valve 11 Water temperature measuring device 12 Steam temperature measuring device 13 Liquid level gauge 14 frame QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10325 A

[0002] AT 263040

[0003] EP 3 701 797 B1

[0004]

Claims

[1] Steam generator, comprising at least a cylindrical combustion chamber made of metallic materials and at least a second cylindrical component made of a metallic material, which has a larger inner diameter than the outer diameter of the cylindrical combustion chamber and a shorter length of the lateral surface between the base surfaces than the cylindrical combustion chamber, and the cylindrical combustion chamber thereby projecting beyond the base surface of the cylindrical component on at least one side, and wherein the cylindrical combustion chamber is arranged within the second cylindrical component with its central axis eccentric to the central axis of the second cylindrical component, and further comprising an opening in a base surface of the cylindrical combustion chamber for introducing fuel, which can be closed by a metallic door,wherein the metallic door and / or the base of the combustion chamber with the opening are in turn provided with at least one further closable opening for the realization of bottom and top air for the combustion chamber, and furthermore the base of the combustion chamber opposite the base with the opening is provided with an opening for a flue pipe with a damper, and furthermore the second cylindrical component is provided in the lower area with a closable drain and / or a closable discharge opening, and furthermore the second cylindrical component has a closable inlet with a non-return valve in the area below the maximum filling level, and furthermore at least one U-shaped metallic siphon is present,which has an opening in the upper inner area of ​​the second cylindrical component and is led from there into the cylindrical combustion chamber over its remaining length and from there through an opening in the upper area of ​​the cylindrical combustion chamber, which in any case is located outside the cylindrical component, and where the opening of the siphon is provided with a distributor, the siphon being provided with a metallic lining in the area of ​​the combustion chamber, and furthermore a weight-loaded pressure relief valve is present in the upper area of ​​the second cylindrical component. [2] Steam generator according to claim 1, wherein the shapes of the base surfaces of the cylindrical combustion chamber and the second cylindrical component are oval, elliptical, egg-shaped, triangular, nearly round, round. [3] Steam generator according to claim 1, in which rib-shaped metal parts are present on the outer shell of the cylindrical combustion chamber at least partially over the circumference of the cylinder. [4] Steam generator according to claim 1, wherein the metallic material used for the cylindrical combustion chamber and / or the rib-shaped parts is steel, cast iron and the metallic material used for the second cylindrical component is steel, stainless steel. [5] Steam generator according to claim 1, wherein the second cylindrical component is insulated on its outside. [6] Steam generator according to claim 1, wherein the rib-shaped metal parts are guided around half the upper circumference of the cylindrical combustion chamber and advantageously between 2 and 20 rib-shaped metal parts are present. [7] Steam generator according to claim 1, wherein the inner diameter of the second cylindrical component is 10 to 100%, advantageously 20 to 50%, larger than the outer diameter with the rib-shaped metal parts of the cylindrical combustion chamber and / or the total length of the cylindrical combustion chamber is 10 to 50% longer than the total length of the second cylindrical component. [8] Steam generator according to claim 1, wherein the closable openings for realizing bottom and top air for the combustion chamber are simultaneously open and closable by means of a rotary slide. [9] Steam generator according to claim 1, wherein pressure gauges, temperature gauges and / or a liquid level gauge are arranged in the middle and / or upper region of the second cylindrical component. [10] Steam generator according to claim 1, in which one or more devices for conveying steam are provided from the distributor at the second opening of the siphon outside the cylindrical combustion chamber. [11] Steam generator according to claim 1, wherein the steam generator is arranged on a frame which has at least two wheels below the steam generator and handles in the upper area of ​​the outer shell of the second cylindrical component. [12] Steam generator according to claim 1, wherein the filling with liquid can also be carried out without pressure using a funnel via the nozzle of the weight-loaded pressure relief valve.

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