Illustrate
The orifice flow meter is use worldwide in gas ,steam and liquid measurement .It has simple structure ,convenient repair ,stable capability,reliable usage etc.
Introduction
Throttle flow equipment which is consist of first time checking piece (throttle flow piece ) and second time equipment (differential pressure transducer and flow totalizer ) ,is also called differential pressure flow meter.
Orifice flow meter is the standard throttle flow piece which can directly produce according to country standard ,need not to customize it .
1 .Country standard GB2624-81 ( the designed installation and usage of the throttle flow equipment of flow measurement ).
2 .International standard ISO5167 ( all kinds of the throttle flow equipment was regulated by international standard organization).
3 .Chemistry plant department standard GJ516-87-HK06.
The outlook of the orifice flow meter
Description
The orifice flow meter which consist of the standard orifice and multi-parameters differential pressure transducer( or differential pressure transducer ,temperature transducer and pressure transducer ), is the differential pressure equipment with high measurement range rate .It can measure the flux of the gas ,steam,liquid and the natural gas , and it is worldwide use in the process control and measurement at the field of the oil ,chemical plant ,metallurgy , electric power ,heat supply and water supply etc.
The application range for the orifice flow meter :
1.Diameter : 15 mm ≤DN≤1200mm
2.Pressure : PN≤10MPa
3.Working temperature : －50℃≤t≤550℃
4.Measurment range rate : 1:10， 1:15
5.Accuracy :0.5 % ,1%
Features:
1.The structure of the throttle flow equipment is easy to copy .It has simple,stable ,reliable capability ,long working life and is very reasonable .
2.The orifice flow meter adopt the international standards and machining .
3.The orifice flow meter is worldwide usage which can measure all the signal-phase flow and it can measure part of mix-phase flow .
4.It is the standard throttle flow equipment which can use without actual flow to calibration .
5.The integrated type is easy to installation ,it can directly connect the differential pressure transducer and pressure transducer without leading a pressure pipe .
Intelligent type features:
Adopted the import differential pressure transducer with intelligence signal crystal silicon.
High accuracy ,perfect self-diagnose function.
It can self-adjust the range of the orifice flow meter through programming .
It can display total flow ,instantaneous flow ,pressure and temperature at the same time .
Beside the online and dynamic complete compensation function ,it has the self-diagnose and self-set measurement range .
Matched manifold communication interface .
High stability .
Wide measurement range ,over 10：1.
Intelligent type technical index:
1 .High accuracy :+/-0.075%
2 .High stable capability : excel 0.1%FS/year
3 .High static pressure : 40MPa
4 .Need not adjust calibration for 5 continuous working life .
5 .It can ignore the effect of the temperature and the static pressure .
6 .Proof high overloading pressure .
Working Principle:
Working Principle:
The running medium which flow through throttle flow equipment ,filled with pipe .
And it form local constriction near the throttle flow ,the flow speed increase . So it can form
the static differential pressure between the upward position and backward position .
And it form local constriction near the throttle flow ,the flow speed increase . So it can form
the static differential pressure between the upward position and backward position .
At the condition of the all known parameters ,it can make a deduction of the relation between
differential pressure and flow range according to the theory of continuous flow and Bernoulli
equation ,then impetrate the flow range .The fundamental formula is as below :
differential pressure and flow range according to the theory of continuous flow and Bernoulli
equation ,then impetrate the flow range .The fundamental formula is as below :
c-output coefficient dimensionless
d-throttling piece of the throttle flow orifice at the working condition or the laryngeal diameter
D-upward internal pipe diameter at the working condition
qm-mass flow Kg/s
qv-volume flow m³/s
ß－diameter rate d/D dimensionless
The density of the running medium Kg/m³
Swellability coefficient dimensionless
- angle shrink pressure
- flange shrink pressure
- D-D/2 shrink pressure
The compose of the throttle flow equipment
1 . the throttle flow pieces : standard orifice plate ,standard nozzle ,long pathway nozzle ,
1/4 circular orifice plate ,double orifice plate ,eccentric orifice plate ,minus circle orifice plate ,
taper entrance orifice plate etc .
2 .fetching pressure equipment :loop chamber ,fetching pressure flange ,holding collar ,
connecting pipe etc .
3 .flange connection ( country standard ,different kinds of standard and other
designed department’s flange ) ,fastener .
4 .measuring tube
