CN201607252U

CN201607252U - Flow meter of Ploba speed uniform tube

Info

Publication number: CN201607252U
Application number: CN201020302306XU
Authority: CN
Inventors: 童复来; 刘德宇
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-02-04
Filing date: 2010-02-04
Publication date: 2010-10-13
Anticipated expiration: 2020-02-04

Abstract

The utility model relates to a flow meter of a Ploba speed uniform tube, which comprises a pressure measuring guide tube, a mounting flange, a fixing base and a detection rod. The fixing base is communicated with the pressure measuring guide tube, the wall of a process pipeline is provided with the mounting hole for axial fixation of the fixing base, the upper end of the detection rod is coaxially arranged in the pipeline of the fixing base, and the other end of the detection rod is arranged on the inner end of the process pipeline along the radial direction. The utility model has simple structure, the cross section of the detection rod is designed to be square, the four corners of the square cross section are all round corners, baffles are arranged along the diagonal lines of the square cross section to divide the square detection rod into two pressure chambers, the structure of the end face is simple and can be manufactured easily, and both the product cost and the operating cost are low.

Description

A kind of Pu Luoba mean velocity tube flowmeter

Technical field

The utility model belongs to the flow metering technical field, relates to flowmeter, especially a kind of Pu Luoba mean velocity tube flowmeter.

Background technology

According to Bernoulli equation, Pitot tube can be measured flow rate of fluid, the version of Pitot tube is: establish a malleation hole over against the flow direction, establish a negative pressure hole back to the flow direction, the pressure-sensitive part of Pitot tube is at the center of pipeline, the flow velocity at measuring channel center multiply by the flow velocity that distribution coefficient is whole pipe.Even because the duct length long enough (be caliber 2040 times), because the viscosity characteristics of fluid, flow rate of fluid is to be symmetrical in the parabola shaped distribution of axis along xsect, therefore Pitot tube is measured the method for rate of flow of fluid with a capping, measuring accuracy is lower, so Pitot tube generally is used for the relatively more even and less demanding pipeline flow measurement of measuring accuracy of velocity flow profile.

In order to overcome the low shortcoming of Pitot tube measuring accuracy, the professional has carried out unremitting effort both at home and abroad in decades.The external sixties in last century begin to release even speed tube, and its test rod shape of cross section has been released designs such as circle, rhombus, mop shape, bullet-shaped, T shape, airfoil.Even speed tube is compared with Pitot tube, has replaced spot measurement by multimetering, and the more accurate flow velocity actual conditions that reflected have improved measuring accuracy.But even speed tube is used in decades, has following three big shortcomings always: 1, test rod shape of cross section complexity, be difficult to make, and cost of products is improved, fetch long price, popularization face is narrow; 2, the pressure port diameter on the test rod is less, the back pressure hole diameter of the product that has little to 2mm or with a diameter only the tubule of 3mm be easy to stop up, and mediation is difficult as the back pressure pipe; 3, instrument coefficient of flow poor linearity, range ratio is little.

Summary of the invention

The purpose of this utility model is to overcome the deficiencies in the prior art, and a kind of Pu Luoba mean velocity tube flowmeter that integrates the advantage of Pitot tube and even speed tube is provided.

The utility model solves its technical matters and is achieved through the following technical solutions:

A kind of Pu Luoba mean velocity tube flowmeter, constitute by pressure conduit, mounting flange, holder and test rod, holder is communicated with the pressure conduit and is installed together, on the made mounting hole of process pipe tube wall, radially install a holder, the upper end of test rod is coaxial to be installed in the pipeline of holder, and the other end of test rod radially is installed in inner end in the process pipe.

And the lower end of described test rod is a blind pipe, and its cross sectional shape is square, and four square ribs are garden dihedral formula; Square diagonal axis in test rod is to installing a dividing plate, this dividing plate is divided into square test rod the low-pressure cavity of the high pressure chest and the lee side of fluoran stream surface, fluoran stream surface symmetric arrangement at test rod has preceding pressure port, lee side symmetric arrangement at test rod has back pressure port, and forward and backward pressure port is communicated with high pressure chest and low-pressure cavity respectively.

And described forward and backward pressure port is 24 pairs and is symmetrical distribution with the process pipe axis.

Advantage of the present utility model and beneficial effect are:

1, this flow measurement accuracy of measurement height: by repeatedly, the actual demarcation of many specifications, have the advantages that the coefficient of flow linearity is good, range ratio is wide, measuring accuracy is high.

2, this flowmeter is difficult for obstruction, stable performance: test rod is an one-piece construction, forms high and low two pressure chambers, and the detection hole in high and low pressure chamber is 24 pairs, is symmetrical distribution with conduit axis, and the diameter of pressure port is 412mm, is difficult for stopping up signal stabilization.

3, this flowmeter structure is simple, operating cost is low: the test rod xsect is designed to square, square four angles are the angle, garden, dividing plate of square diagonal angle tape, square test rod is divided into two pressure chambers, and end face structure is simple, is easy to make, low cost product, operating cost is lower.

Description of drawings

Fig. 1 is structural front view of the present utility model (being cut-open view in the process pipe);

Fig. 2 is the longitudinal cross-section enlarged diagram of the test rod of Fig. 1;

Fig. 3 is that the A-A of Fig. 2 is to the structure cut-open view.

Embodiment

The utility model is described in further detail below by specific embodiment, and following examples are descriptive, is not determinate, can not limit protection domain of the present utility model with this.

A kind of Pu Luoba mean velocity tube flowmeter referring to Fig. 1, is made of pressure conduit 1, mounting flange 2, holder 3 and test rod 4, and holder is communicated with test rod and is installed together, and the upper end of test rod is coaxial to be installed in the pipeline of holder; Be shaped on the mounting hole (not having label) of the about 40mm of a diameter on the tube wall of process pipe 5, holder radially is packed on the mounting hole of process pipe, and the other end of test rod radially is installed in inner end in the process pipe.

The structure of test rod is referring to Fig. 2, Fig. 3, and its lower end is a blind pipe, and its cross sectional shape is square, and four square ribs are garden dihedral formula; Square diagonal axis in test rod is to installing a dividing plate 7, and this dividing plate is divided into two pressure chambers with square test rod, and fluoran stream surface is a high pressure chest, and lee side is a low-pressure cavity; Pressure port 6 before the fluoran stream surface symmetric arrangement of test rod has, lee side symmetric arrangement at test rod has back pressure port 8, forward and backward pressure port is communicated with high pressure chest and low-pressure cavity respectively, and forward and backward pressure port is 24 pairs and is symmetrical distribution with the process pipe axis that the diameter of pressure port is 4-12mm.

Claims

1. Yi Zhong Pu Luoba mean velocity tube flowmeter, constitute by pressure conduit, mounting flange, holder and test rod, holder is communicated with the pressure conduit and is installed together, it is characterized in that: on the made mounting hole of process pipe tube wall, radially install a holder, the upper end of test rod is coaxial to be installed in the pipeline of holder, and the other end of test rod radially is installed in inner end in the process pipe.

2. Pu Luoba mean velocity tube flowmeter according to claim 1 is characterized in that: the lower end of described test rod is a blind pipe, and its cross sectional shape is square, and four square ribs are garden dihedral formula; Square diagonal axis in test rod is to installing a dividing plate, this dividing plate is divided into square test rod the low-pressure cavity of the high pressure chest and the lee side of fluoran stream surface, fluoran stream surface symmetric arrangement at test rod has preceding pressure port, lee side symmetric arrangement at test rod has back pressure port, and forward and backward pressure port is communicated with high pressure chest and low-pressure cavity respectively.

3. Pu Luoba mean velocity tube flowmeter according to claim 2 is characterized in that: described forward and backward pressure port is 24 pairs and is symmetrical distribution with the process pipe axis.