CN205561940U - Circular pipeline total cross -section flow measuring device - Google Patents

Abstract

The utility model belongs to the technical field of flue gas flux measuring equipment, the utility model aims to provide a difficult jam, and the measuring accuracy is high, long service lifetime, reliable and stable circular pipeline total cross -section flow measuring device, in circular pipeline on the same cross -section, arrange four group's sampling pipes along the circumference quadrature, every group sampling pipe includes ram -air pipe and static tube, ram -air pipe and static tube arrange back -to -back, facining the wind to seting up a plurality of total head thieff hatchs on the ram -air pipe, a plurality of static pressure thieff hatchs are seted up to the last direction opposite of static tube, no interference and accurate detection result, and the setting sweeps the device, it sweeps regularly to carry out the reversion to ram -air pipe and static tube and each fairlead, possess and prevent stifled deashing function, the difficult jam, the maintenance volume is little, stability and reliability are realized, long service lifetime, can be continuous, accurate on line measurement arranges the complicacy, the disorderly interior flue gas velocity (flow) of industrial waste gas pipeline in flow field, the environmental administration can be satisfied and the on -line monitoring accuracy is carried out to exhaust emission, the requirement of continuity and reliability.

Description

Circular pipe total cross-section flow measurement device

Technical field

This utility model belongs to flue gas flow technical field of measuring equipment, particularly relates to a kind of circular pipe total cross-section flow measurement Device.

Background technology

At present, the general fashion that industrial waste gas flow velocity (flow) is measured is for using one sample point of tradition (point is measured) or several Measuring point (line measurement) metering system, it only just can accurately measure flue gas under the conditions of uniform flow field or relatively uniform flow field Flow, if flow field is uneven or in the case of disorder, point is measured and the mode of line measurement flow all cannot accurately measure this section Mean flow rate.But at the industrial gas emission pipeline of the industries such as electric power, oil and chemical industry due to reality such as technique and space restrictions Situation, exhaust piping is extremely difficult to the straight length measuring condition in uniform flow field or relatively uniform flow field, so conventional point is measured and line The mode measuring flow all cannot represent the average speed in discharge duct cross section, and error of measured data is the biggest, according to on-the-spot actual Comparability test error is typically at more than 10-20%, it is impossible to meets environmental administration and carries out the requirement of on-line monitoring, also cannot be as to row Dirty enterprise carries out the foundation of collection of drainage dues.

CN1475776A discloses a kind of cross section effusion meter, and static tube horizontal positioned, total head average tube erects peace in the middle part of flange Putting, this total head average tube top left and right sides connects 4 ram-air pipes respectively, also connects another root in total head average tube right side central complete Pressure pipe, this effusion meter, compared with some measurement, line metering system, improves the accuracy of measurement data.But this effusion meter is in reality During use, easily blocking, maintenance workload is big, and fragile, service life is short, and due to ram-air pipe, the layout of static tube Mode is chaotic, and measurement result yet suffers from the problem that error is big, accuracy is low.

Utility model content

The technical problems to be solved in the utility model be to provide one be not easily blocked, measurement accuracy height, length in service life, stable Circular pipe total cross-section flow measurement device reliably.

For solving above-mentioned technical problem, this utility model adopts the following technical scheme that

A kind of circular pipe total cross-section flow measurement device, including four groups of sampling tubes of circumferentially quadrature arrangement, often group sampling tube bag Include ram-air pipe and static tube, ram-air pipe and static tube to arrange back-to-back, windward to offering some total head thieff hatchs on ram-air pipe, Offer some static pressure thieff hatchs on static tube in contrary direction, often one end of group ram-air pipe and static tube is respectively with sampling block even Connecing, arrange total head sampling cavity and static pressure sampling cavity in sampling block, ram-air pipe, static tube sample with total head sampling cavity, static pressure respectively Chamber connects, and sampling block fixes sampling head, offers total head sampling passage, static pressure sampling passage in sampling head respectively, and total head samples Passage, static pressure sampling passage connects with total head sampling cavity, static pressure sampling cavity respectively, and the total head sampling passage of sampling head, static pressure take Sample passage is connected with differential pressure transmitter through total head fairlead, static pressure fairlead respectively, on total head fairlead, static pressure fairlead respectively Install and measure electromagnetic valve, scavenging pipeline the most in parallel on total head fairlead, static pressure fairlead, scavenging pipeline is installed blowback electromagnetism Valve, scavenging pipeline is connected with blow device, often ram-air pipe, the outer end stationary positioned flange of static tube, positioning mode in group sampling tube Blue fixing with flange sleeve is connected.

This utility model circular pipe total cross-section flow measurement device, further, another sidewall of described sampling block is fixed standby Use sampling head.

This utility model circular pipe total cross-section flow measurement device, further, total head thieff hatch on every described ram-air pipe Quantity is chosen as 4 or 5, the total head thieff hatch on each ram-air pipe to arrange position identical, static pressure thieff hatch and total head are adopted The quantity in sample hole is equal and position is corresponding.

This utility model circular pipe total cross-section flow measurement device, further, the internal diameter of described total head thieff hatch is preferably 6mm or 8mm or 10mm, the internal diameter of total head thieff hatch is less than or equal to the 1/2 of ram-air pipe internal diameter, and the static pressure of correspondence position is sampled Hole is identical with the internal diameter of total head thieff hatch.

This utility model circular pipe total cross-section flow measurement device, further, described blow device uses air compressor.

This utility model circular pipe total cross-section flow measurement device, further, described ram-air pipe and static tube use rustless steel Pipe.

This utility model circular pipe total cross-section flow measurement device compared with prior art, has the advantages that in circle In pipeline on same cross section, circumferentially four groups of sampling tubes of quadrature arrangement, often group sampling tube includes ram-air pipe and static tube, ram-air pipe Arrange back-to-back with static tube, windward to offering some total head thieff hatchs on ram-air pipe, static tube is offered in contrary direction Some static pressure thieff hatchs, static pressure thieff hatch is equal with the quantity of total head thieff hatch and position is corresponding, the static pressure sampling of correspondence position Hole is identical with the internal diameter of total head thieff hatch, and arranges sampling block and sampling head, and when measuring gas flow, this is measured by total head thieff hatch The average total head in cross section, static pressure thieff hatch measures the average static pressure on this cross section, after calculating further according to Bernoulli equation and get final product Going out cross section average discharge, measurement result is accurate, within certainty of measurement is up to ± 3%, and arranges blow device, periodically to ram-air pipe Carrying out reverse blow with static tube and each fairlead, possess anti-blocking deashing function, be not easily blocked, maintenance is little, reliable and stable, Service life is long, and this utility model measurement apparatus on-line measurement continuous, accurate can arrange industrial waste gas complicated, that flow field is disorderly Flue gas flow rate (flow) in pipeline, has the advantage that on-line measurement data are continuous, accurate, reliable and stable and working service amount is little, Disclosure satisfy that environmental administration carries out the requirement of on-line monitoring accuracy, seriality and reliability to waste gas discharge.

Below in conjunction with the accompanying drawings circular pipe total cross-section flow measurement device of the present utility model is described further.

Accompanying drawing explanation

Fig. 1 is the overall diagram of this utility model circular pipe total cross-section flow measurement device installment state；

Fig. 2 is the front view of sampling tube part in Fig. 1；

Fig. 3 is the sectional view of sampling tube part.

Detailed description of the invention

As shown in Figure 1-Figure 3, this utility model circular pipe total cross-section flow measurement device includes four groups of circumferentially quadrature arrangement Sampling tube, often group sampling tube includes that ram-air pipe 1 and static tube 2, ram-air pipe 1 and static tube 2 use stainless steel tube, ram-air pipe 1 Arrange back-to-back with static tube 2, windward to offering some total head thieff hatchs 11 on ram-air pipe 1, contrary on static tube 2 Some static pressure thieff hatchs 21 are offered in direction.This utility model is primarily adapted for use in the circular pipe of internal diameter Φ 3001mm-Φ 8000mm, Internal diameter according to circular pipe determines the quantity of thieff hatch, and internal diameter is the biggest, arranges quantity the most, and on every ram-air pipe 1, total head is adopted The quantity in sample hole 11 is chosen as 4 or 5, the total head thieff hatch 11 on each ram-air pipe 1 to arrange position identical, total head The internal diameter of thieff hatch 11 is preferably 6mm or 8mm or 10mm, and the internal diameter of total head thieff hatch 11 is less than or equal in ram-air pipe 1 The 1/2 of footpath, static pressure thieff hatch 21 is equal with the quantity of total head thieff hatch 11 and position is corresponding, the static pressure thieff hatch of correspondence position 21 is identical with the internal diameter of total head thieff hatch 11.By repetition test, the internal diameter of thieff hatch is carried out preferably, and according in pipeline Footpath select thieff hatch quantity is set, further increase the accuracy of measurement.Thieff hatch quantity is set and position meet " Gu Determine solid particulate matter in polluter aerofluxus to measure and the gaseous contaminant method of sampling " requirement of (GB/T16157-1996).

Often one end of group ram-air pipe 1 and static tube 2 is connected with sampling block 3, arranges total head sampling cavity 31 and static pressure in sampling block 3 Sampling cavity 32, ram-air pipe 1, static tube 2 connect with total head sampling cavity 31, static pressure sampling cavity 32 respectively.On sampling block 3 admittedly Determine sampling head 4, in sampling head 4, offer total head sampling passage 41, static pressure sampling passage 42, total head sampling passage 41, quiet respectively Pressure sampling passage 42 connects with total head sampling cavity 31, static pressure sampling cavity 32 respectively.Fix standby on another sidewall of sampling block 3 Sampling head 5, when sampling head 4 blocking needs to change, can temporarily be measured by standby sampling head 5, it is ensured that the company of measurement Continuous property.

The total head sampling passage 41 of sampling head 4, static pressure sampling passage 42 respectively through total head fairlead 6, static pressure fairlead 7 with poor Pressure transmitter 8 connects, and each sampling head 4 can individually connect a set of differential pressure transmitter, it is also possible to as it is shown in figure 1, adjacent two Sampling head is connected to same set of differential pressure transmitter.Be respectively mounted on total head fairlead 6, static pressure fairlead 7 measurement electromagnetic valve 61, 71.Scavenging pipeline 9 the most in parallel on total head fairlead 6, static pressure fairlead 7, scavenging pipeline 9 is installed blowback electromagnetic valve 91, Scavenging pipeline 9 is connected with blow device 92, and blow device 92 uses air compressor.

In order to prevent the internal blocking of measurement apparatus, blow device 92 is set, PLC controls periodically ram-air pipe 1 and static tube 2 And each fairlead carries out reverse blow, source purge gas is provided by air compressor, and pressure is 0.5MPa, and blowback electromagnetic valve 91 is flat Shi Quanguan, when purging, first closes the measurement electromagnetic valve on total head, static pressure fairlead, is then turned on blowback electromagnetic valve, carry out Purging, closes blowback electromagnetic valve, opens the measurement electromagnetic valve on total head, static pressure fairlead after having purged, continue to measure, really Protect measurement accuracy.

Often ram-air pipe 1, the outer end stationary positioned flange 12 of static tube 2 in group sampling tube, locating flange 12 is by bolt and flange Set 13 is fixing to be connected, and uniformly offers four installing holes 14, by four flange sleeve 13 points during installation on circular pipe 10 sidewall It is not welded in four installing holes 14, thus measurement apparatus is arranged on circular pipe 10.

The measurement process of this utility model circular pipe total cross-section flow measurement device is: in circular pipe 10 on same cross section, Circumferentially four groups of sampling tubes of quadrature arrangement, total head fairlead 6 and the static pressure fairlead 7 of four groups of sampling tubes are respectively connected to a set of differential pressure Transmitter 8, when measuring gas flow, the average total head in this cross section measured by total head thieff hatch 11, and static pressure thieff hatch 21 is then measured Average static pressure on this cross section, differential pressure transmitter 8 exports 4-20mA signal to Data collection and precessing system, according to Bernoulli Jacob Equation draws cross section average discharge after calculating.Flue gas flow computing formula is:

$Q=KA\sqrt{\frac{2\mathrm{\Δ}P}{\mathrm{\ρ}}}$

Wherein, K is discharge coefficient；A is sectional area (m²)；Δ P is differential pressure (Pa)；ρ is gas density (kg/m³)。

This utility model circular pipe total cross-section flow measurement device is widely used in electric power, oil and chemical industry etc. through dedusting, de- The flow measurement of waste gas discharge in the circular pipe of nitre and desulfurization, is mainly carried out circular industrial exhaust gas pipeline waste gases discharge capacity online Measure in real time and monitoring, and monitoring data and information are sent to environmental protection authorities, it is ensured that to blowdown enterprise pollution thing discharge capacity In real time monitoring and total amount add up.

Embodiment described above is only to be described preferred implementation of the present utility model, not to of the present utility model Scope is defined, and on the premise of without departing from this utility model design spirit, those of ordinary skill in the art are to this utility model The various deformation made of technical scheme and improvement, all should fall in the protection domain that this utility model claims determine.

Claims (6)

1. a circular pipe total cross-section flow measurement device, it is characterised in that: include four groups of sampling tubes of circumferentially quadrature arrangement, Often group sampling tube includes that ram-air pipe and static tube, ram-air pipe and static tube are arranged back-to-back, some to offering windward on ram-air pipe Total head thieff hatch, static tube is offered some static pressure thieff hatchs in contrary direction, and often one end of group ram-air pipe and static tube is respectively Is connected with sampling block, samples in block and total head sampling cavity and static pressure sampling cavity are set, ram-air pipe, static tube respectively with total head sampling cavity, Static pressure sampling cavity connects, and sampling block fixes sampling head, offers total head sampling passage, static pressure sampling passage in sampling head respectively, Total head sampling passage, static pressure sampling passage connects with total head sampling cavity, static pressure sampling cavity respectively, the total head of sampling head sample passage, Static pressure sampling passage is connected with differential pressure transmitter through total head fairlead, static pressure fairlead respectively, total head fairlead, static pressure fairlead On be respectively mounted measurement electromagnetic valve, respectively scavenging pipeline in parallel on total head fairlead, static pressure fairlead, scavenging pipeline is installed anti- Blowing electromagnetic valve, scavenging pipeline is connected with blow device, often ram-air pipe, the outer end stationary positioned flange of static tube in group sampling tube, Locating flange is fixing with flange sleeve to be connected.

Circular pipe total cross-section flow measurement device the most according to claim 1, it is characterised in that: described sampling block another Standby sampling head is fixed on one sidewall.

Circular pipe total cross-section flow measurement device the most according to claim 2, it is characterised in that: every described ram-air pipe The quantity of upper total head thieff hatch is chosen as 4 or 5, the total head thieff hatch on each ram-air pipe to arrange position identical, static pressure Thieff hatch is equal with the quantity of total head thieff hatch and position is corresponding.

Circular pipe total cross-section flow measurement device the most according to claim 3, it is characterised in that: described total head thieff hatch Internal diameter be preferably 6mm or 8mm or 10mm, the internal diameter of total head thieff hatch less than or equal to the 1/2 of ram-air pipe internal diameter, corresponding position The static pressure thieff hatch put is identical with the internal diameter of total head thieff hatch.

Circular pipe total cross-section flow measurement device the most according to claim 4, it is characterised in that: described blow device is adopted Use air compressor.

6. according to the circular pipe total cross-section flow measurement device described in any one of claim 1-5, it is characterised in that: described entirely Pressure pipe and static tube use stainless steel tube.