RU2172803C2 - Underground fire hydrant - Google Patents

Abstract

FIELD: water supply system. SUBSTANCE: fire hydrant has column with valve installed on fire stand in inspection pit. Lower part of fire stand is provided with cylindrical insert accommodating impeller which is free to rotate on shaft aligned with stand axis; magnetically permeable tips are installed on ends of impeller blades. Hole is made in cylindrical insert body to receive hollow plug; the latter accommodates parallel-connected coil-and-core assembly and diode; anode of mentioned diode is connected to starting lead of coil and to ground; finishing lead of coil is connected to corrector input by means of sealed cable passed inside shielding case and telescopic tube one of whose ends is hinged to shielding case; in addition, fire hydrant is provided with hermetically sealed shielded housing accommodating normalizer, electrical energy storage, electronic switch, and meter-annunciator connected in series by means of mentioned corrector. EFFECT: provision for measuring total water discharge (for certain period of time) with aid of fire hydrant and ensuring remote reading of discharge (outside inspection pit). 3 cl, 1 dwg

Description

 The invention relates to the field of mining and construction, in particular to technical means of water supply, intended for water intake from the water supply network, and can be used in water supply networks equipped with fire hydrants.

 Known fire hydrants are of a simplified type, including a column mounted on a fire stand with a nut fixed in it, a vertical rod with a thread included in the nut, and a ball valve that locks the bottom hole of the column from the side of the fire stand [see: N.N. Abramov, N .N. Geniev, V.I. Pavlov: Water supply. -M.: Gosstroyizdat, 1958, p. 125]. The opening of such a hydrant is carried out by rotating the handle of the portable part - the stander. During rotation of the vertical hydrant rod articulated with the stander handle in the indicated nut, the lower shaft end presses on the hydrant valve ball. When the valve ball is recessed, the passage of water from the main to the hydrant column opens, and from it to the stander and then through the stub pipe to the water consumer. The main advantage of such hydrants is the simplicity of their design and the lack of great effort exerted on the handle of the stander when closing the hydrant. However, analog solutions have drawbacks that limit their widespread use in the water supply networks of large cities. Their locking is carried out due to the positive buoyancy of the valve ball when lifting the hydrant rod. This circumstance prevents the use of such a hydrant with a passage section of its column of more than 75 mm. A light ball with large sections of the column does not withstand high water pressure in the line. In addition, the design of such hydrants does not provide the ability to account for the flow of water through the hydrant.

 Disadvantages of solutions - analogues are partially eliminated in the fire hydrant of the underground type, including a column with a valve installed in a well on a fire stand [see Textbook for high schools: Abramov N.N. Water supply. - M.: Stroyizdat, 1974, p.129-130] - prototype.

 Since the valve of such a hydrant is connected to the rod, the valve body can be made of durable material that does not have positive buoyancy. This allows the use of such hydrants with large flow areas. However, the disadvantage of analog solutions associated with the inability to account for the flow of water through the hydrant, the prototype solution does not eliminate. This disadvantage of underground type fire hydrants significantly worsens the economic performance of the water supply system, as it allows numerous consumers of tap water to carry out unauthorized and free water intake from hydrants for watering streets, green spaces, washing, etc. For a water supply system, the inability for well-known hydrants to take into account the flow of water through a hydrant does not make it possible to identify the places of such unauthorized water withdrawals, and if a “violator” is found, it is possible to present a justified claim indicating the amount of damage.

 The solution to this problem cannot be carried out by simply equipping fire hydrants with one of the known types of flow meters. The fact is that mechanical flowmeters based on measuring the water flow rate by the impeller associated with a mechanical transmission meter cannot be protected from blocking the impeller from the upper section of the inspection well, if such flowmeters are installed in the hydrant column or at its outlet. If they are installed on a fire main, it is impossible to take their testimony without digging up hydrants. Non-contact flow meters (electromagnetic, optical, nuclear magnetic, thermal, etc.) require a power supply and, in addition, in relation to tap water, the transparency and ionic composition of which are subject to seasonal fluctuations, cannot provide acceptable measurement accuracy [see e.g. Bobrovnikov G.N. , Novozhilov B.M., Sarafanov V.G. Contactless flowmeters. - M.: Mechanical Engineering, 1985].

 The objective of the invention is to eliminate the noted drawback, namely, providing the ability to measure the total (over a certain period of time) water flow through the hydrant while ensuring that remotely (outside the viewing well) take the flow readings. The need for remote sensing of information on the total flow rate is dictated by the fact that the observation wells, in which hydrants of the underground type are located, are usually filled with water (it is mandatory during the intake of water) or mud, and in winter this mud forms a difficult to dig out monolith.

 The technical result is achieved by the fact that in the well-known underground type fire hydrant, including a column with a valve installed in a well on a fire stand, additional nodes and new connections between the nodes are introduced, namely, the well is an inspection well, the lower part of the fire stand is supplemented with a cylindrical insert, in which there is placed an impeller freely rotating on an axis coinciding with the axis of the stand, with a diameter corresponding to the diameter of the cylindrical insert, and at the ends of the impeller blades lugs are made of magnetically conductive material, while in the case of the cylindrical insert in the plane of rotation of the lugs a hole is made in which a hollow tube is sealed, in the cavity of which are placed a parallel connected coil with a magnetic core and a diode, the anode of which is connected to the beginning of the coil winding and to the "mass" ", and the end of the coil winding is connected to the input of the correction device using a sealed cable passing inside the protective casing, fixed to the flanges of the fire stand and covering the stopper in the casing of the fire stand, and a telescopic tube, one end of which is pivotally connected to the protective casing, while the fire hydrant is additionally equipped with a protective sealed casing attached to the other end of the telescopic tube, and placed in it in series with the indicated corrective device, normalizer, drive electric energy, an electronic key and a numbering meter. In addition, the protective casing is fixed to the flanges of the fire stand with the help of half rings, and an ionistor is used as an energy storage device.

 The idea of the invention is to measure the flow rate of water through a fire hydrant using an unloaded impeller placed in a cylindrical insert complementary to the fire stand. The angular velocity of rotation of such an impeller is proportional to the flow rate and, therefore, the value of the instantaneous volumetric flow rate of water through the hydrant, which can be described by the relation ω = kQ, (1) where ω is the angular velocity of rotation of the impeller, radian / s; k is the coefficient of proportionality, depending on the geometry of the impeller and the cross-sectional area of the insert, radian / l; Q - instantaneous volumetric flow rate of water, l / s.

 The isolation of the total flow rate in the proposed technical solution is reduced to the integration over time of the number of current pulses flowing through the winding of the magnetic core coil at the moment the tip of the magnetically conductive material placed at the end of the impeller blade passes by it. In this case, the energy of the sum of current pulses is accumulated in the drive and serves as a source for moving the disk of the counter-numbering by one “click”, after which the process of energy storage is repeated. The ability to remotely remove information from the numbering counter in the proposed technical solution is provided by extending the telescopic tube beyond the viewing well, at the end of which there is a numbering counter. Moreover, even the freezing of dirt in the inspection well cannot be an obstacle to the extension of the telescopic tube, since one of its constituent tubes extends from the other tube, and not from the mud.

 We show the materiality of the distinguishing features.

 The introduction of the impeller hydrant and its placement in the cylindrical insert of the fire stand is a new solution for fire hydrants. It provides the establishment of an unambiguous relationship between the flow of water through the hydrant and the speed of the impeller. The cylindrical insert essentially plays the role of a nozzle enhancing the action of the impeller. In addition, the cylindrical insert provides a volume in which the impeller rotates freely. There is no place for an impeller in the fire stand of the prototype solution. Placing the impeller exactly in the fire stand provides its protection against unauthorized actions of water consumers taken to distort the readings of water flow through the hydrant. On the stander side, the impeller in the proposed solution is reliably protected by a closed hydrant valve, and the pressure in the open hydrant is so great that it can push something flexible through the stender’s nozzles and then through the hydrant column and its open valve to the impeller in the fire stand to block it, practically impossible.

 The introduction of a magnetic core coil into the hydrant is a new solution. It is combined with the placement at the ends of the impeller blades of tips from a magnetically conductive material, which provides excitation of voltage pulses in the coil. The amplitude of these pulses is greater, ceteris paribus, the smaller the air (or liquid) layer between the core of the coil and the magnetically conductive tip. Therefore, an essential distinguishing feature is the placement of the coil in the plug screwed into the casing of the fire stand in the plane of rotation of the tips.

 The introduction of a diode into the fire hydrant and its connection with the coil so that the anode of the diode is connected to the beginning of the coil winding and to ground is a new solution. It provides shunting of the negative half-wave voltage.

 The introduction of a corrective device into the hydrant and its connection with a coil with a magnetic core is a new solution. It provides an “exhibition” of meter readings in accordance with the indications of an exemplary totalizing flowmeter installed at the output of the stand when calibrating measuring instruments (hydrant).

 The introduction of a normalizer is a new solution. It provides the same shape of the pulses entering the drive input, regardless of the speed of rotation of the impeller. (With a higher speed of rotation of the impeller at the output of the coil, the voltage amplitude will be greater, and the pulse duration will be shorter).

 The introduction of an electric energy storage device and its connection with a magnetic core through a correcting device and a normalizer is a new solution for hydrants. It ensures the accumulation of the energy of current pulses converted into an electric charge in an amount corresponding to the response energy of the numbering counter. Moreover, the use of a predominantly ionistor as a storage ring is also a new solution for hydrants. It provides high accuracy in measuring the water flow due to the fact that, due to the very large electric capacity of the ionistors, the moment of the start of their discharge can be “assigned” to the exponential characteristic of the ionizer charge in the linear section of the numbering meter. In other words, using an ionistor as an electric energy storage device allows you to accurately measure the amount of charge on it used to drive the meter-numbering device.

 The introduction of an electronic key into the hydrant is a new solution. It provides storage charge to a strictly set voltage value (charge value and voltage across the capacitor, the ionistor is essentially a capacitor, functionally connected). Then the key is opened, and the drive is discharged to the numbering counter.

 The introduction of a telescopic tube hydrant, a protective casing into the hydrant, the placement of a corrective device, a normalizer, a drive, an electronic key and a numbering counter in a sealed enclosure and the connection of the telescopic tube to the casing with a hinge is a new solution. It provides protection of the measuring path of the hydrant from unauthorized or accidental actions that could lead to distortion of the meter-numbering. The implementation of the telescopic tube, extendable at a distance of at least one meter, provides the ability to read the counter-numbering without digging the hydrant or without draining the well, by simply grabbing the end of the telescopic tube and extending it to a distance convenient for reading the meter. Since the upper section of the underground hydrant is located at a depth of 150-400 mm relative to the upper section of the viewing well, the possibility of extending the telescopic tube at the end of which is the numbering counter allows you to take readings of the latter and the nearsighted person, bringing the numbering meter close to your eyes. (The remaining ≈ 600 mm with a "deep" arrangement of the hydrant corresponds to the height of the desk). The swivel connection of the protective casing and the tube provides ease of operation of the hydrant (access for maintenance personnel to the well, flow control when a stand is installed, etc.).

 The fastening of the protective casing with the help of half rings to the flanges of the fire stand provides the exception of uncontrolled removal of the measuring path of the hydrant. Half rings can be removed only after blocking the fire line (relieving pressure in it) by unscrewing the fasteners of the flange connection (it is necessary to unscrew 4 of 6 bolts tightening the flanges in a row with this fastening). The overlapping of the main leads to a change in the parameters of the water supply network controlled by the duty service of the water supplying enterprise and, therefore, does not go unnoticed.

 The essence of the proposed technical solution is illustrated by the drawing, which shows a block diagram of the proposed fire hydrant of the underground type.

Fire hydrant contains:
1 - fire stand,
2 - column fire hydrant,
3 - hydrant valve,
4 - a viewing well.

Blocks 1. ..4 characterize the prototype. In addition to blocks 1 ... 4, new units and blocks have been introduced into the fire hydrant:
5 - cylindrical insert fire stand. It is a length of pipe sufficient to accommodate the impeller.

 6 - impeller. The device of impellers for flowmeters is described, for example, in [Aviation equipment / Yu.A. Andrievsky, Yu.E. Voskresensky, Yu.P. Dobrolensky et al. / Ed. Yu.P. Dobrolensky. -M .: Military Publishing, 1989 (Combat aircraft), p. 85]. Since the impeller is unloaded (not connected by any transmission to the drive of any mechanism), it can be made of lightweight polymeric material, and its attachment points to the fire stand can be made from the same material (impeller axis, wheel rim, spokes wheels, the axis of which is the axis of the impeller). At the same time, the impeller can be attached to the fire stand in the traditional way for hydrants - by placing the rim (otherwise the impeller clips) in the ring groove of the lower flange of the fire stand, followed by fixing the rim when tightening the flanges.

 7 - tips of magnetically conductive material at the ends of the impeller blades.

 8 - a hollow plug with a thread corresponding to a thread in the hole of the body of the cylindrical insert 5, made in the plane of rotation of the tips 7. The plug 8 can be made of a polymer material, which ensures a tight connection between the plug and the body of the insert 5.

 9 - coil with a magnetic core. Such coils are widely used in the radio industry. In particular, such coils are located in handsets.

 10 - a diode connected with its anode to the beginning of the winding of coil 9 and to the “mass”, and the cathode to the end of the winding of coil 9. Coil 9 and diode 10 are placed in the cavity of the tube 8, which, after placing these parts, is filled with a compound, forming a tight integral part - plug 8 with two leads: a ground contact and a lead for connecting a communication cable.

 11 - a protective casing. It can be a L-shaped tube, put on the tube 8 at one end and having a hinge at the other end. Inside the tube, the communication cable of the coil 9 with other blocks of the proposed device is laid.

 12 - the attachment of the protective cover 11 to the flanges of the fire stand 1. Since the length of the fire stand may be different for various modifications of fire hydrants, the mount 12 can be made sliding.

 13 - telescopic tube made sliding at a distance of at least one meter. The lower end of the tube 13 is pivotally connected to the casing 11. The telescopic tube 13 and its articulated connection with the casing 11 are similar to the retractable antennas of portable radios.

 14 - a protective sealed housing attached to the end of the tube 13.

 15 - corrective device, the input of which is connected to the output of the coil 9 (to the end of its winding). In the simplest case, it is a voltage divider, which is used as a variable resistor [see, for example, To help the ham radio: Collection. Vol. 109 / Comp. I.N. Alekseeva. - M .: Patriot, 1991, p. 15-24].

 16 - normalizer. Pulse normalizers are widely known. In the simplest case, the normalizer is a capacitor, the input of which is supplied with a voltage pulse, and the output of which is shunted by a semiconductor zener diode. The normalization of pulses in such a normalizer is based on a constant charge time of its capacitor at a constant pulse amplitude. The constant voltage applied to such a capacitor is ensured by the zener diode, and the constant charge time is provided by the constant value of the product RC, where R is the resistance of the charge circuit, C is the capacitance of the capacitor. Capacitors are described, in particular, in the above source, p. 41-79.

 17 - Electric energy storage device. Various types of such drives are known, in particular capacitors. Recently, ionistors, otherwise molecular storage rings, have become more widespread. Due to the large capacity (1-3 Farads with the size of a ruble coin), the use of an ionistor in the proposed solution makes it possible to ensure greater accuracy of the measuring path of the hydrant due to the extended linear portion of the dependence of the voltage across the ionistor on the charge current.

 18 is an electronic key. As it can be used low-power thyristor [see, for example, Semiconductor devices. Thyristors. Directory. - St. Petersburg: publishing house RNII "Electrostandard", 1993], a switching diode is a dynistor or microcircuit, which ensures a negative slope of the current-voltage characteristic after the electronic switch is turned on. (Otherwise, do not discharge the ionistor onto the armature of the counter-numbering armature).

 19 - counter numbering. As it can be used a device such as a telephone counter [see A.A.Sanin: Electronic devices of nuclear physics. - M.: Nauka, 1964, p. 377]. For the operation of such a counter-numbering, a current pulse of several mA for several ms is sufficient.

 Since the control current of the counter-numbering device is small, all the radio components can be miniature and combined into a single chip. For comparison, it can be noted that quartz watches with hands, in essence, are also an electromechanical counter-numbering, driven by current pulses generated, unlike the technical proposal under consideration, by a built-in self-oscillation generator powered by a miniature battery.

где V - скорость течения воды в пожарной подставке, м/с;
Q - расход воды через гидрант, м³/с;
D - диаметр пожарной подставки, м.Fire hydrant works as follows. When the stander is installed on the fire hydrant and the hydrant valve body 3 is lowered by means of the stander handle, water begins to flow through the fire support 1. The speed of its flow at a known flow through the hydrant can be determined from the known dependence [see , for example, N.N. Abramov, N.N. Genius, V.I. Pavlov. Water supply.- M.: Gosstroyizdat, 1958, p. 49]:

where V is the water flow rate in the fire stand, m / s;
Q - water flow through the hydrant, m ³ / s;
D is the diameter of the fire stand, m

 With an internal diameter of the fire stand of 170 mm and a typical flow rate of 5 l / s, the flow velocity is ~ 0.22 m / s, and with a flow rate of 30 l / s, which occurs with both the stender nozzles open and the rubberized fire hoses, 1.32 m / s The flow rate of an open fire hydrant when filling, for example, a watering machine, can correspond to a water speed of up to 5 m / s through a fire stand. The impeller 6 rotates in such a flow, and when the tip 7 passes over the magnetic core of the coil 9, a voltage pulse is excited in its winding, the amplitude of which is determined by the number of turns of the winding, the speed of rotation of the impeller by the minimum distance from the tip 7 to the plug 8 and other factors. The negative half-wave of the pulse is shunted by the diode 10, and the positive creates a current in the circuit: the correcting device 15 - the normalizer 16 - the electrical energy storage 17. The number of such pulses per second is equal to the product of the number of revolutions per second of the impeller by the number of impeller blades (from the point of view of dynamic balancing of the impeller is desirable place tips 7 on each impeller blade 6). Each such pulse increases the charge of the drive 17 by a certain amount, ultimately increasing the voltage on the drive 17. Since the normalizer 16 normalizes the pulses, i.e. all pulses at its output have the same amplitude and duration, then the charge speed of the drive depends on the number of revolutions of the impeller 6 and the resistance value of its charge circuit installed in the correcting device 15. When the charge on the drive 17 reaches a certain value corresponding to the voltage on it, the key is opened 18, and the drive is discharged to the winding of the armature of the counter-numbering 19, causing the rotation of its first disk by one division. When the voltage on the drive is reduced during its discharge to a certain value corresponding to the closing voltage of the key 18, the key is locked and the charge process of the drive is repeated again. The counter-numbering 19 in this case saves the readings, and they cannot be changed downward by the supply of any external current pulses.

 Thus, the integration of the water flow through the hydrant in the proposed solution is carried out twice: first, by the electric energy storage device 17, and then by the numbering meter 19. This makes it possible to measure the total water flow through the hydrant for virtually unlimited time without “overfilling” the discharge disks of the numbering meter. To take the readings of the counter-numbering device 19, it is enough to hook the end of the telescopic tube 13 and extend it beyond the limits of the well 4. After taking the readings, the tube is again “shortened” and placed in the inspection well 4 in a position convenient for the personnel serving the water supply networks, for which the swivel connection a protective casing 11 and a telescopic tube 13.

 Thus, based on the analysis of the structure and functioning of the scheme of the proposed technical solution, we can conclude that the underground fire hydrant in which this technical solution is implemented has the advantages that meet the objective of the invention: providing the ability to measure the total water flow through the hydrant when possible to take readings without digging or draining the manhole. In addition, the implementation of this technical solution meets the goals of resource-saving technologies, as it contributes to the saving of tap water, the preparation of which is associated with significant costs of resources and materials. The implementation itself does not require the use of rare and expensive materials.

 The proposal was developed at the level of a technical proposal for one of the objects of the State Unitary Enterprise Vodokanal of St. Petersburg.

Claims (3)

 1. Fire hydrant of underground type, including a column with a valve installed in a well on a fire stand, characterized in that the well is an inspection well, the lower part of the fire stand is supplemented by a cylindrical insert in which an impeller with a diameter of corresponding to the diameter of the cylindrical insert, and at the ends of the impeller blades installed tips of magnetically conductive material, while in the housing of the cylindrical insert in the plane is rotated The tips have a hole in which a hollow plug is hermetically sealed, in the cavity of which are placed a parallel connected coil with a magnetic core and a diode, the anode of which is connected to the beginning of the coil winding and to ground, and the end of the coil winding is connected to the input of the correction device using a sealed a cable passing inside the protective casing fixed to the flanges of the fire stand and closing the plug in the housing of the fire stand, and a telescopic tube, one end of which is pivotally connected to Barrier casing, wherein the fire hydrant is further provided with a secure hermetic housing attached to the other end of the telescopic tube and placed in it serially connected said correcting device, normalizer, storage of electrical energy and an electronic key-counter numerator.  2. Fire hydrant underground type according to claim 1, characterized in that the protective casing is fixed to the flanges of the fire stand with the help of half rings.  3. Fire hydrant of underground type according to claim 1 or 2, characterized in that an ionistor is used as an electric energy storage device.