Foam generator

Abstract

The utility model discloses a foam generator which adopts the principle that a floating sleeve is pushed by inlet pressure and is closed by pressing the floating sleeve downwards by a spring after being sprayed. The problems that existing sealing glass is fragile, the crushing pressure is different, and fragments enter a finished product oil tank are solved, and the device belongs to the field of fire safety. The device mainly comprises a nozzle, a floating sleeve, a sealing ring, a shell, an O-shaped sealing ring, a cover plate and a spring, the nozzle is screwed at an inlet of the shell, the cover plate is fixed at the upper end of the shell through bolts, the floating sleeve is inserted below the shell, and the spring is arranged between the floating sleeve and the cover plate; during working, foam mixed liquid enters the shell through the nozzle, upwards pushes the floating sleeve and sucks air, and the foam mixed liquid passes through the foam outlet transverse pipe and the foam outlet flange to form foam covering and extinguish fire; the method has wide application prospects in petrochemical storage tanks, civil aviation fuel oil, military oil depots and white wine cellars.

Description

Technical Field

[0001] This utility model relates to a foam generator installed on the top of a storage tank in a foam fire extinguishing system. The foam generator sprays foam mixture into the storage tank after it expands and foams by absorbing air, covering the oil surface and isolating the air to extinguish the fire. It adopts the principle of imported pressure pushing open the float sleeve and spring pressing down to seal the float sleeve after spraying. The foam generator belongs to the field of fire safety. Background Technology

[0002] Currently, fixed-roof and internal floating-roof crude oil and refined oil storage tanks are equipped with several foam generators on their tops. These tanks include petrochemical storage tanks, civil aviation fuel tanks and lubricating oil tanks, power plant oil tanks, military oil depots, and liquor cellars. In case of fire, the fire pump station delivers foam mixture to the foam generators on top of the hazardous chemical storage tanks, breaking the sealed glass inside the foam generators, drawing in air, generating foam, and spraying it to cover the oil surface, isolating the air and extinguishing the fire. Normally, to prevent flammable, explosive, toxic, and harmful gases volatilized from the storage tanks from drifting out through the foam generators, polluting the air, and causing deflagration, the foam generators are sealed with flat glass plates. However, during transportation, in summer when exposed to high temperatures from the sun, and in winter when the storage tanks are heated by steam, the temperature difference between the inside and outside of the glass often causes the glass plates to break. This allows flammable, explosive, toxic, and harmful gases inside the storage tanks to drift out through the air inlets of the foam generators, polluting the air, and potentially causing serious accidents such as deflagration when encountering static electricity or lightning.

[0003] Currently, the sealing glass plate inside the foam generator has its surface engravings done manually, making it difficult to control the force applied. The glass plate is rigidly secured with upper and lower metal pressure plates and several bolts. Due to the different coefficients of thermal expansion and contraction between metal and glass, if the engravings on the glass plate are too heavy, the sealing glass plate may break accidentally during transportation, in summer high temperatures, or when heated by oil vapors in the storage tank in winter, causing toxic gas leaks and spread. If the engravings on the glass plate are too light, the foam mixture may not be able to break the glass plate or may only partially break it during spraying, resulting in fire extinguishing failure.

[0004] After fire linkage testing and foam discharge during a fire, the sealing glass of traditional foam generators will shatter. This requires climbing to the top of the storage tank, which is tens of meters high, to remove dozens of bolts from the cover plate and glass pressure plate, and replace the sealing glass. This is outdoor high-altitude work, which poses a risk of falling. The glass fragments can enter the finished oil tank, affecting the quality of the oil and creating a hazard for users. Current foam generators cannot meet the fire safety requirements of petrochemical storage tanks, military oil depots, power plant oil tanks, civil aviation oil tanks, and liquor cellars. Summary of the Invention

[0005] To address the problems of easily broken, non-reusable, and high-risk replacement operations of the sealing glass plates in existing foam generators, this utility model provides a foam generator that adopts the principle of pushing open the floating sleeve with imported pressure and then pressing down to seal the floating sleeve after spraying. It consists of: a nozzle (1), a floating sleeve (2), a sealing ring (3), a housing (4), bolts (5), an O-ring seal (6), a cover plate (7), and a spring (8). The housing (4) comprises: a vertical pipe (a), a foaming vertical pipe (b), a foaming flange (c), a foaming horizontal pipe (d), an inclined bottom plate (e), and a liquid inlet. The flange (f) is welded together; the nozzle is screwed to the inlet of the shell, the cover plate is fixed to the upper end of the shell with bolts, the float sleeve is inserted under the shell, and a spring is provided between the float sleeve and the cover plate. The sealing ring is embedded in the groove at the top of the vertical pipe. Normally, the float sleeve is pressed down by the spring, and the shoulder of the float sleeve presses against the sealing ring to achieve a seal. When working, the foam mixture enters the shell through the nozzle, compresses the spring, pushes the float sleeve upward, draws in air through the air inlet, foams and expands, and the foam mixture flows through the gourd-shaped hole of the float sleeve into the foam outlet horizontal pipe and the foam outlet flange to form foam covering the oil surface and achieve fire extinguishing.

[0006] This invention is implemented as follows: The foam generator consists of a nozzle, a float sleeve, a sealing ring, a shell, bolts, an O-ring, a cover plate, and a spring. The shell is welded together from a vertical pipe, a foaming vertical pipe, a foaming flange, a foaming horizontal pipe, an inclined bottom plate, and an inlet flange. The float sleeve is welded together from an upper cylinder and a lower cylinder. The nozzle is screwed to the inlet of the shell, and the cover plate is fixed to the upper end of the shell with bolts and sealed with an O-ring. The float sleeve is inserted under the shell, and a spring is provided between the float sleeve and the cover plate. The sealing ring is embedded in the groove at the top of the vertical pipe. Normally, the float sleeve is pressed down by the spring, and the shoulder of the float sleeve presses against the sealing ring to achieve a seal, preventing the leakage of toxic, harmful, flammable, and explosive gases volatilized in the tank. During operation, the foam mixture enters the shell through the nozzle, compresses the spring, and pushes the float sleeve upward. Air is drawn in through the air inlet, and the foam expands. The foam mixture flows through the gourd-shaped hole in the lower cylinder of the float sleeve into the foaming horizontal pipe and the foaming flange, forming foam that covers the surface of the oil in the tank and isolates the air to extinguish the fire.

[0007] The beneficial effects of this utility model are as follows: It solves the problem that the sealing glass of existing products breaks during transportation, in summer high temperatures, and in winter when the oil vapor in the storage tank is heated due to temperature differences between the inside and outside of the glass, causing toxic gas leaks; it resolves the defects of the sealing glass not being completely broken and the amount of foam released being insufficient during a fire; it eliminates the hidden danger of glass fragments and debris entering the finished oil tank and damaging the quality of the oil; it avoids the problems of high risk and low maintenance efficiency when replacing the glass at height; it realizes the repeated opening and closing function, eliminating the operation of replacing the glass at height outdoors and improving maintenance efficiency; the shell is welded from stainless steel pipes, which improves the service life on marine island project sites and solves the hidden danger of paint and galvanized anti-corrosion treatment layers on the surface of traditional steel foam generators peeling off and entering the storage tank after long-term exposure to outdoor sun, wind, rain, oxidation and aging; after spraying, water will not accumulate at the bottom of the foaming vertical pipe, avoiding damage from freezing and expansion; it meets the fire safety requirements of petrochemical, military, civil aviation, and brewing industries. Attached Figure Description

[0008] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0009] Figure 1 This is a main cross-sectional view of the structure of this utility model.

[0010] Figure 2 This is a cross-sectional view of the working state of this utility model.

[0011] Figure 3 This is a cross-sectional view of the sealing ring of this utility model.

[0012] Figure 4 This is a cross-sectional view of the nozzle of this utility model.

[0013] Figure 5 This is a top view of the nozzle of this utility model.

[0014] The technical solution adopted by this utility model to solve its technical problem is:

[0015] By improving the traditional disposable sealing glass plate to a floating sleeve seal, repeated opening and closing performance is achieved, eliminating the risks of replacing glass plates at high altitudes outdoors and improving maintenance efficiency. It also avoids the problem of glass fragments from existing products entering the finished oil tank and contaminating the oil quality. During spraying, the floating sleeve has upper and lower positioning, ensuring flexible and reliable descent. The inclined bottom plate allows residual liquid to flow out by its own weight after spraying, solving the risk of liquid accumulation and freezing cracking in the foam generator. The shell and floating sleeve are made of corrosion-resistant materials, preventing galvanized layers and paint from entering the storage tank, ensuring oil quality and extending the service life of the foam generator. Detailed Implementation

[0016] The foam generator consists of: a nozzle, a float sleeve, a sealing ring, a housing, bolts, an O-ring, a cover plate, and a spring. The housing is welded from: a vertical pipe, a foaming vertical pipe, a foaming flange, a foaming horizontal pipe, a sloping base plate, and a liquid inlet flange. The float sleeve is made of aluminum-magnesium alloy and is welded from an upper cylinder and a lower cylinder, which are concentric. The upper cylinder has dozens of evenly machined oblong holes on its cylindrical surface, and the lower cylinder has dozens of evenly machined gourd-shaped holes on its cylindrical surface. The sum of the cross-sectional areas of the gourd-shaped holes is 1.2 times the cross-sectional area of ​​the foaming horizontal pipe. Dozens of air inlets are machined on the lower side of the vertical pipe of the housing; the cumulative cross-sectional area of ​​these holes is 8 times the cross-sectional area of ​​the nozzle to ensure sufficient air intake for foaming. The lower end of the cover plate has two rings, a smaller one... The ring serves as a spring seat, and the large ring serves as a floating sleeve positioning seat. The nozzle is screwed tightly to the housing inlet, using an O-ring for static sealing. The cover plate is bolted to the upper end of the housing, also using an O-ring for static sealing. The floating sleeve is inserted into the vertical tube of the housing, with a large clearance fit between the floating sleeve and the vertical tube. A spring is installed between the floating sleeve and the cover plate. The sealing ring is embedded in the groove at the top of the vertical tube. The rectangular part of the sealing ring on the left side is embedded in the groove at the top of the vertical tube and is secured with sealant. Two sealing grooves are designed on the upper surface. The right side of the sealing ring is angled at 15°. The sealing ring surrounds and encloses the outer wall of the vertical tube to ensure airtight performance. Normally, the floating sleeve moves downward under the action of the spring and its own weight. The shoulder of the floating sleeve presses against the sealing ring, with a positive pressure of 0.02MPa on the bubbling flange side. At a negative pressure of 0.01 MPa, maintain airtightness and prevent leakage of flammable, explosive, toxic, or harmful gases from the storage tank. During operation, when the foam mixture is at 0.25 MPa, the bottom of the float sleeve is subjected to a 1960 N pushing force, which pushes the float sleeve upward, compresses the spring, and causes the float sleeve to rise to the lower surface of the cover plate. The foam mixture enters the shell through the nozzle and draws in air through dozens of air inlets below the vertical pipe, causing foaming and expansion. The top of the float sleeve contacts the cover plate, and the top of the upper cylinder of the float sleeve is positioned at the float sleeve positioning seat at the lower end of the cover plate. The lower cylinder of the float sleeve is positioned inside the vertical pipe, ensuring that the float sleeve does not shift or deform during the high-pressure, high-flow-rate spraying of the foam mixture. A reinforcing rib is riveted around the top edge of the upper cylinder of the float sleeve to ensure that the float sleeve does not collide with the cover plate under high pressure. When the cover plate is hit, it does not deform; the foam mixture is sprayed from the foam outlet horizontal pipe and foam outlet flange through dozens of gourd-shaped holes in the lower cylinder of the float sleeve, covering the oil surface and isolating air to extinguish the fire; the gourd-shaped holes cause the flowing foam mixture to be subjected to irregular compression, making the foaming more uniform and sufficient; after the fire is extinguished, the supply of foam mixture is stopped, and the float sleeve moves downward under the action of spring and its own weight, and the shoulder of the float sleeve presses against the sealing ring to achieve a seal; the inclined bottom plate of the shell allows the residual liquid after the foam is sprayed to be discharged by its own weight, and there is no water accumulation in the foam generator, preventing freezing and cracking accidents; the lower side of the outer circle of the nozzle is a straight thread, and the upper side of the outer circle of the nozzle is a cone. The water inlet of the inner cavity is a cone, and the water outlet is a cylinder. Two inclined 30° lines are symmetrically machined on the cylindrical surface. °The rectangular groove promotes liquid flow rotation, ensuring a more uniform mixture and more thorough foaming. The sealing ring has an η-shaped cross-section, with a rectangle on the left and a flat surface at the top. Two sealing grooves are designed on the flat surface to ensure airtightness under positive and negative pressure. The right side of the sealing ring is inclined at 15° with an η-shaped cross-section, which makes the sealing ring have a larger bonding contact surface and a longer service life.

[0017] 1) Material: The nozzle is made of copper alloy, the cover plate, spring, housing and bolts are made of low carbon stainless steel, the float is made of aluminum-magnesium alloy; the sealing ring and O-ring are made of EPDM rubber.

[0018] 2) Rated flow rate of foam generator: 960 L / min;

[0019] 3) Expansion ratio: ≥6n;

[0020] 4) 25% precipitation time: ≥2.5 min;

[0021] 5) Gas seal: No leakage under positive pressure 0.02MPa and negative pressure 0.01MPa;

[0022] 6) Working pressure range: 0.3-1.2 MPa;

[0023] 7) Floating sleeve lifting pressure: 0.25 MPa;

[0024] 8) Floating sleeve top thrust: 1960N;

[0025] This invention has broad application prospects in petrochemical storage tanks, civil aviation fuel and lubricating oil tanks, power plant oil tanks, military oil depots, and liquor cellars.

Claims

1. A foam generator, characterized in that: The principle of using imported pressure to push open the float sleeve and then pressing down on the float sleeve to seal it after spraying is adopted. The foam generator consists of: nozzle (1), float sleeve (2), sealing ring (3), shell (4), bolt (5), O-ring seal (6), cover plate (7), and spring (8). The nozzle is screwed to the inlet of the shell, the cover plate is fixed to the upper end of the shell with bolts, the float sleeve is inserted under the shell, and a spring is provided between the float sleeve and the cover plate. The sealing ring is embedded in the groove at the top of the vertical pipe. Normally, the float sleeve is pressed down by the spring, and the shoulder of the float sleeve presses down on the sealing ring to achieve sealing. When working, the foam mixture enters the shell through the nozzle, pushes the float sleeve upward, draws in air, foams and expands. The foam mixture is sprayed out from the foam outlet horizontal pipe and foam outlet flange through the hole of the lower cylinder of the float sleeve to form foam, which covers the oil surface, isolates the air, and extinguishes the fire.

2. The foam generator according to claim 1, characterized in that: The floating sleeve is welded together from an upper cylinder and a lower cylinder. The upper and lower cylinders are concentric. The cylindrical surface of the upper cylinder is uniformly machined with waist-shaped holes, and the cylindrical surface of the lower cylinder is uniformly machined with dozens of gourd-shaped holes.

3. The foam generator according to claim 1, characterized in that the sealing ring has an η-shaped cross-section, with a rectangle on the left and a plane at the top, two sealing concave lines designed on the plane, and a 15° angle on the right.

Images