RU1827546C - Tachometric flow transducer - Google Patents

Abstract

Usage: in instrumentation, two measurements of liquid and gas flow rates. The inventive device comprises a housing 1 with inlet and outlet 3 holes, a calibrated channel 4, a flow turbulator 5, a primary converter in the form of a turbine 6, a signal pickup unit 7. The flow turbulator 5 can be made in the form of a twisted conical spiral, either fixed to top, either for a larger turn, or in the form of a flat spiral. The top of the spiral is mounted on the insert 8 and can be covered with a fairing 9. 3 zp f-ly. 5 ill.

Description

The invention relates to instrumentation and can be used to measure the flow of liquids and gases in the oil, chemical industry and energy.

The present invention is based on the task of creating a sensor for a tachometric flow meter, the design of which would make it possible to extremely reduce the own hydraulic resistance of the turbulator, to prevent the gradual accumulation of foreign impurities on its surface and their falling into the supports of the primary flow transducer, which would reduce hydraulic losses, improving the reliability and stability of operation when measuring the flow rates of solids fluids.

Figure 1 shows a tachymeter flowmeter sensor with a tangential turbine and a turbulator in the form of a conical spiral attached to the walls of the calibrated channel behind the base; figure 2 the sensor of the tachometric flowmeter with a tangential turbine and a turbulator in the form of a conical spiral attached to the body at the top; in Fig. 3, a tachometric flowmeter sensor with an axial turbine and a turbulator in the form of a conical spiral attached to the walls of the calibrated channel at the base; figure 4 - sensor tachometric flowmeter with an axial turbine and a turbulator in the form of a conical spiral attached to the housing at the top; 5 is a tachometric flowmeter sensor with an axial turbine and a flow turbulator in the form of a flat spiral.

The tachometer flowmeter sensor comprises a housing 1 with input 2 and output 3 holes, a calibrated channel 4 for a controlled medium, a flow turbulator in the form of a twisted conical spiral 5 located in a calibrated channel 4, and a primary transducer in the form of a turbine 6, which can be either tangential (Fig. 1.2) and axial (Fig. 3.4), node

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signal collection 7. Vita conical spiral 5 is fixed in the housing 1 at the entrance to the calibrated channel A, There are various options for fastening the conical spiral 5 to the housing 1. It can be attached to the coils with a maximum diameter or to the top using insert 8. In the first case, the stiffness conical spiral 5 should be such that the velocity head of the medium being measured does not change its geometric dimensions. In the second case, the top of the conical spiral 5 in the place of its attachment to the insert 8 can be closed by a fairing 9 and installed relative to the walls of the calibrated channel 4 with a certain gap 10.

Various variations of the shape of the spiral are possible, for example, the angle at the apex of the conical spiral 5, for which it is mounted in the housing 1, can be not only sharp, but also obtuse.

It is possible to perform a spiral 5 flat (Fig. 5) and fixed in the housing 1 to the central turns. Moreover, in the last two cases, the implementation of an elastic spiral is most appropriate.

The device operates as follows.

When measuring the flow rates of fluids, the flow, which was still laminar at the lower measurement limit, passes through a calibrated channel 4, flowing around the conical spiral 5 and becomes turbulent. Then, the turbulent flow enters the blades of the turbine 6, which is mounted on bearings in the housing 1. The rotation speed of the turbine 6 is measured by the signal pick-up unit 7. The operation of the device at a flow rate that was laminar becomes equivalent to the operation in a turbulent mode and therefore the measurement range extends into low cost side, and measurement accuracy is improved. Moreover, due to the orientation of the spiral 5 with its apex toward the inlet 2, in comparison with its orientation with the apex toward the outlet 3, the hydraulic losses of the sensor are significantly reduced.

Additional benefits are provided by attaching the conical spiral 5 to the apex with a gap 11 between its base and the walls of the calibrated channel 4 in which the flow through the turns of the spiral 5 causes its oscillatory movement, which helps to remove foreign matter from the surface of the spiral 5 into the gap zone 11. In addition, oscillatory motion increases flow turbulization. For an axial impeller sensor, similar mounting and

the placement of the turbulator ensures the extrusion of extraneous inclusions on the periphery of the calibrated channel 4 and prevents the bearings of the turbine 6 from clogging.

In the case of using a flow turbulator in the form of a conical spiral 5 with an obtuse angle at the apex or in the form of a flat spiral (Fig. 5) fixed to the apex or

0 central turn, spiral stiffness 5 is calculated in accordance with the value of the velocity head of the medium to be measured, so that its effect in the zone of obviously turbulent flow ensures an increase in the gaps between the turns.

Due to the increase in the gaps between the turns of the spiral 5, its hydraulic resistance in the self-similar zone of the sensor is reduced.

0 The proposed tachometric flowmeter sensor has a hydraulic resistance much lower than the known one; moreover, it eliminates the need for frequent dismantling and cleaning of both the turbulizer flow5 and the turbine bearings, which ensures increased reliability and stability when measuring flow rates of solid inclusions.

Claims (4)

1. The tachometer flow meter sensor, comprising a housing with inlet and outlet openings and a calibrated channel for a controlled environment, a turbulator 5 a stream in the form of a twisted conical spiral placed in a calibrated channel, a primary transducer in the form of a turbine and a signal pick-up unit, characterized in that. in order to reduce hydraulic losses, increase reliability and stability when measuring the flow rates of solids, the conical spiral is oriented with its apex towards the inlet opening. 2. The sensor according to claim 1, characterized in that. that the conical spiral is fixed to the top, and its base is installed relative to the walls of the calibrated channel with 0 clearance. 3. The sensor according to claim 1, characterized in that the conical spiral is made with an obtuse angle at the apex. 4. A tachometric flowmeter sensor 5, comprising a housing with inlet and outlet openings and a calibrated channel, a flow turbulator in the form of a spiral placed in a calibrated channel, a primary converter in the form of a turbine, and a signal pickup unit, characterized in the fact that, in order to reduce hydraulic losses, increase the reliability and stability of work when measuring costs fluids with solid inclusions, the spiral is made flat and fixed in the housing to the central turns. (pv & f 7 S J / 3 rig.Z in g b rie.2 t 4 ff tpt / gL