CN201477107U - Device for measuring flow velocity and flow rate of gas under higher pressure - Google Patents

Abstract

The utility model discloses a device for measuring the flow velocity and the flow rate of gas under higher pressure, which comprises a double-segment screwed pipe, a screw thread sealing cap, a wide strip arranged between the double-segment screwed pipe and the screw thread sealing cap, and a pitot tube which is coiled and packed by the wide strip, which jointly complete the measurement. When the device is used, the wide strip which is arranged between the double-segment screwed pipe and the screw thread sealing cap replaces cotton yarn or macerated fabric to coil and pack the pitot tube, the double-segment screwed pipe and the screw thread sealing cap complete the fixation to replace manual sealing, and degree scale on the pitot tube completes the measurement by means of selecting points on the different positions of the cross section of a pipeline. The manual sealing workload, the difficulty, and the harm to a human body caused by higher-temperature or higher-pressure airflow are greatly reduced, and the damage to downstream equipment caused by suctioning and coiling the cotton yarn and the macerated fabric into the pipeline is reduced, and therefore, the measurement is simple, convenient, safe and reliable.

Description

A kind of under elevated pressures the device of measurement gas flow rate

Technical field

The utility model relates to a kind of device of measurement gas flow rate, relate in particular to a kind of under elevated pressures the device of measurement gas flow rate.

Background technology

At present, in the measurement of industry spot pipeline conventional gas flow, often be divided into direct measurement and measurement indirectly, adopt the dynamic pressure pressure measurement to belong to the method for indirect measurement, this method is used many, is especially containing dust and smog is bigger, is not easy to directly carry out the place of flow measurement.Because it is simple in structure, be convenient to make, adopt flow velocity-area-method, be used widely industrial.In practical operation was measured, gaging hole was held at the scene successfully often, and seals with plug, waited for in-site measurement, adopted the less of on-the-spot online detection, also there is no need.But because operating condition usually is (to comprise malleation or negative pressure) under elevated pressures, adopt Pitot tube to measure dynamic pressure, adopt cotton yarn and cloth waste leak stopping wind, finish measurement.Because pressure is higher, many times also follow the air-flow of higher temperature simultaneously, artificial plug-hole is very painstaking, and can be because accidentally, under negative pressure condition, cotton yarn and cloth waste are sucked and involve in the pipeline, cause upstream device, as the damage of blower fan; Under barotropic condition, the air-flow ejection causes personal injury etc., and all especially severes that leaks out under two kinds of situations have greatly influenced the accuracy of measuring as a result.Therefore, how rapid and convenient solves this class the problems referred to above that the measurement gas flow rate exists under elevated pressures, to guaranteeing the accuracy of measurement result, rationally has according to instructing commercial production effectively, has bigger practical significance.

The utility model content

The technical matters that the utility model solved provide a kind of under elevated pressures the device of measurement gas flow rate, solve existing a large amount of industry spot elevated pressures and measure the problem that exists.

The technical solution of the utility model is: a kind of under elevated pressures the device of measurement gas flow rate, comprise two section threaded line pipes, the screw thread sealing cap places the wide band among both, and is finished measurement jointly by the Pitot tube of wide band winding up.

As a kind of improvement of the present utility model, described wide band is the wide band of heatproof.

As another improvement of the present utility model, described Pitot tube has graduated scale.

Of the present utility model under elevated pressures the device of measurement gas flow rate, can also include the thread jacket pipe.

The utility model in use, by to place the loose band winding up Pitot tube among two section threaded line pipes and the screw thread sealing cap to replace cotton yarn or cloth waste, finish the fixing manpower shutoff that replaces by two sections threaded line pipes and screw thread sealing cap, by the scale on the Pitot tube, finish Pitot tube on pipeline section diverse location get point measurement.Greatly reduce manpower shutoff workload, degree of difficulty and higher temperatures or higher pressure air-flow and the injury of the person and cotton yarn, cloth waste are sucked involve in the pipeline, cause damage, thereby guarantee to measure simple and easy to do, safe and reliable upstream device.

Description of drawings

Fig. 1 is a structural representation of the present utility model.

Fig. 2 is the structural representation of another embodiment of the utility model.

Embodiment

Below in conjunction with accompanying drawing, further specify the utility model by embodiment.

In an embodiment, if when the gaging hole that pipe under test is opened is internal thread, adopt the mode shown in the accompanying drawing 1 to implement; When if the gaging hole that pipe under test is opened is external thread, adopt the mode shown in the accompanying drawing 2 to implement, screw thread sealing cap 6 sizes are determined that by on-the-spot gaging hole two sections threaded line pipe 3 endoporus determine that according to the size of the Pitot tube 2 that passes through Pitot tube 2 length are chosen according to the survey pipe diameter.

Referring to accompanying drawing 1, promptly should under elevated pressures, form the Pitot tube 2 that comprises two section threaded line pipes 3, the wide band 5 of heatproof, screw thread sealing cap 6 and band scale by the device of measurement gas flow rate.Two sections threaded line pipes 3 are connected on the screw thread gaging hole of measuring tested pipeline when measuring by lower thread, after wideer band 5 winding ups of heatproof being lived Pitot tube 2, put into two section threaded line pipes 3 epimere chambeies, cover and screw screw thread sealing cap 6, wide strap 5 of heatproof just has been closedly fixed like this, enter in the gas pipeline by the flexible Pitot tube of scale in accordance with regulations, and the measuring junction that makes Pitot tube is correctly met to airflow direction, draw dynamic pressure by the pressure gauge that connects Pitot tube, and then try to achieve speed and flow according to dynamic pressure and length velocity relation formula.

$v=\mathrm{<figure-callout\; id="2"\; label="K"\; filenames="H2009202335659E00011.png"\; state="\{\{state\}\}">K</figure-callout>}\sqrt{\frac{2\&CenterDot;\mathrm{\&Delta;p}}{\mathrm{\&rho;}}}$

In the formula: v---gas flow rate, m/s;

K---Pitot tube coefficient;

Δ p---the average dynamic pressure of measuring point place gas, Pa;

ρ---measuring point place gas density, kg/m ³

When the two section of rotation threaded line pipe makes Pitot tube survey mouth vertical with airflow direction, but the static pressure of gas in the measuring channel.

Implement referring to the mode shown in the accompanying drawing 2, its key is a component devices when being internal thread than gaging hole, and many threaded outer tubes 7 couple together a band external thread gaging hole and two section threaded line pipes by its, and all the other are identical when implementing all to be internal thread with above-mentioned gaging hole.

The utility model is to measure at original simple dependence Pitot tube, lean on manpower to leak out to be improved to and adopt two section threaded line pipes with the cotton yarn shutoff, threaded outer tube is (optional, only have during for external thread) at the gaging hole of pipe under test, the screw thread sealing cap, and place the wide band of heatproof among both, finished measurement jointly by the band scale Pitot tube of the wide band winding up of heatproof.

According to propose with measurement requirement this under elevated pressures the device of measurement gas flow rate, because in use, by to place (heatproof) the loose band winding up Pitot tube among two section threaded line pipes and the screw thread sealing cap to replace cotton yarn or cloth waste, by two sections threaded line pipes, threaded outer tube is (optional, only have during for external thread at the gaging hole of pipe under test) and the screw thread sealing cap finish the shutoff of fixing replacement manpower, by the scale on the Pitot tube, finish Pitot tube on pipeline section diverse location get point measurement.Greatly reduce manpower shutoff workload, degree of difficulty and higher temperatures or higher pressure air-flow and the injury of the person and cotton yarn, cloth waste are sucked involve in the pipeline, cause damage, thereby guarantee to measure simple and easy to do, safe and reliable upstream device.

Claims (4)

1. the device of a measurement gas flow rate under elevated pressures is characterized in that: comprise two section threaded line pipes (3), screw thread sealing cap (6) places the wide band (5) among both, and is finished measurement jointly by the Pitot tube (2) of wide band (5) winding up.

2. the device of measurement gas flow rate according to claim 1 is characterized in that: described wide band (5) is the wide band of heatproof.

3. according to the device of the measurement gas flow rate described in claim 1 or 2, it is characterized in that: described Pitot tube (2) has graduated scale.

4. according to the device of the measurement gas flow rate described in the claim 1, it is characterized in that: also include thread jacket pipe (7).

Images