CN2440201Y

CN2440201Y - Intelligent vortex-street flow meter

Info

Publication number: CN2440201Y
Application number: CN 00254621
Authority: CN
Inventors: 苏林波; 陈宝荣
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-09-22
Filing date: 2000-09-22
Publication date: 2001-07-25
Anticipated expiration: 2010-09-22

Abstract

The utility model relates to a vortex-street flow meter which is composed of a display meter, a connecting rod, a signal transducer, a probe, a triangle post, a shell body, etc., wherein, an inner cavity of the shell body is composed of a straight tube and two symmetrical conical tubes. The straight tube is arranged at the middle section of the inner cavity. The conical tubes with certain conicity are arranged at both ends of the straight tube. The two conical tubes are formed to be an inlet and an outlet of the inner cavity. The maximum diameter of each of the conical tubes is the nominal diameter. The improved vortex street flow meter overcomes the disadvantages that small flow is difficult to meter, and a measuring range ratio is narrow. The occupancy rate of the vortex street flow meter to the production and the sale of flow metering instruments is increased. The utility model satisfies the requirements of a user to carry out metering to the unstable flow of the small flow.

Description

Intelligence whirlpool, street flowmeter

This novel a kind of flowmeter, particularly a kind of vortex shedding flow meter of relating to.

Vortex shedding flow meter is a kind of new flowmeter instrument that the seventies grows up, though it is historical short, but owing to having the development that advantage that many instrument can not possess simultaneously obtains to advance by leaps and bounds concurrently, but, because the inherent defect that vortex shedding flow meter exists, low discharge is difficult to metering, but also to consider long straight length to be installed at the two ends of flowmeter, Gu in the application process of reality, certain limitation is arranged, accuracy of detection from present domestic and international various model vortex shedding flow meters, full packages small-bore (referring generally to below 200mm) vortex shedding flow meter, many in 8: 1～15: 1 range ability with regard to measuring liquid, its measuring accuracy generally is+and 1,0%, the vapour survey precision is+1,5%.

Because vortex shedding flow meter is in the flow range of regulation, the accuracy of measuring grade of flowmeter, fundamental error just comply with relevant regulations, this for working flow in continuous variation, long-term work is in the industrial and mining enterprises of the flow range of flux lower limit and overshoot, select for use vortex shedding flow meter to be subjected to significant limitation, thereby can not satisfy user's requirement.

This novel purpose is: design a kind of novel intelligent vortex shedding flowmeter, to obtain satisfied flow measurement range and precision.

To achieve these goals, basis is novel improves original vortex shedding flow meter housing inner chamber, inner chamber is made up of the Taper Pipe of straight-run of pipe and two sections symmetries, its stage casing is a straight tube, the straight tube two ends are the Taper Pipe that has certain taper, two sections Taper Pipes have formed the entrance and exit in the inner chamber, and the maximum gauge of Taper Pipe is a nominal diameter, and the nominal diameter of Taper Pipe is respectively the inlet end and the endpiece of inner chamber; The length L of straight tube can be 0.7～0.9 times of nominal diameter, and the cone angle of Taper Pipe can be 5 °～65 °.

Adopt as above structure, changed the measurement range of vortex shedding flow meter, remedied the not shortcoming of energy measurement low discharge of common vortex shedding flow meter, particularly reduced the installation requirement of vortex shedding flow meter, the front and back straight length of the flowmeter when making originally for installation requires to have become 3 present * D～5 * D (wherein D is a nominal diameter) by 10 original * D～40 * D, installs and becomes very convenient.Because this structure of employing increases the speed that flows through probe, can not detected frequency in the time of can obtaining low discharge, and can produce stronger vortex, and because this device and original device have dwindled the diameter of straight tube under identical nominal diameter, so produce flow field very uniformly in the time of can obtaining the low discharge state, thereby finish the measurement of low discharge.The increase of the vortex shedding flow meter highly significant after the improvement measurement range of flowmeter, make the range ratio when measuring liquid bring up to 35: 1 by original 13: 1, range ratio during measurement gas can be brought up to 20: 1 by original 8.6: 1, and the range ratio when measuring steam can be brought up to 20: 1 by original 13: 1.From as can be seen above, vortex shedding flow meter after the improvement has overcome low discharge and has been difficult to measure the shortcoming narrow with range ratio, increase the occupancy of vortex shedding flow meter in the flow-meter production and sales, satisfied the requirement that the user measures low discharge and unstable flow.

Illustrate below in conjunction with example:

Fig. 1 is the vortex shedding flow meter before improving

Fig. 2 cuts open for the A-A of Fig. 1

Fig. 3 connects flowmeter for the whirlpool after improving

Fig. 4 cuts open for the A-A of Fig. 1

Vortex shedding flow meter is made up of indicator gauge 1, connecting link 2, signal transducer 3, probe 4, triangular prism 5, housing 6, inner chamber etc.

As can be seen from Figure 1, housing 2 inner chambers are straight tube 7, and DN is a nominal diameter.

The inner chamber of the housing 6 among Fig. 2 is made up of straight-run of pipe 7 and two sections Taper Pipes 8,9, Taper Pipe 8,9 both sides at straight tube 7, the minimum diameter of Taper Pipe 8,9 is identical with straight tube 7 diameters, the maximum gauge of Taper Pipe 8,9 is the nominal diameter DN that the whirlpool connects flowmeter, also be the inlet end 10 and the endpiece 11 of inner chamber, cone angle tapering α is 5 °～65 °, it is identical that whirlpool before shape, effect and the installation site of the triangular prism 5 in the inner chamber and the improvement connects flowmeter, still in straight length 7, its size cooperates in corresponding straight tube diameter both can, identical with prior art, state no longer in addition.

When choosing nominal diameter DN is 80, and straight tube 7 diameters are chosen as 65, and length of straight pipe selects 46.4, and cone angle is the present invention of 30 ° of making, and the I of the flow of measurement reaches 2.5～90m ³/ h.

Claims

1. intelligent vortex shedding flowmeter, form by indicator gauge, connecting link, signal transducer, probe, triangular prism, housing etc., it is characterized in that: the housing inner chamber is made up of the Taper Pipe of straight-run of pipe and two sections symmetries, its stage casing is a straight tube, the straight tube two ends are the Taper Pipe that has certain taper, two sections Taper Pipes have formed the entrance and exit in the inner chamber, and the maximum gauge of Taper Pipe is a nominal diameter.

2. intelligent vortex shedding flowmeter according to claim 1 is characterized in that: the length L of straight tube can be 0.7～0.9 times of nominal diameter, and the cone angle of Taper Pipe can be 5 °～65 °.