JB/T 9249-1999 (JB/T 9249-2015 Newer Version) PDF English
JB/T 9249-1999 (JB/T9249-1999, JBT 9249-1999, JBT9249-1999)
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Newer version: JB/T 9249-2015 Standards related to (historical): JB/T 9249-2015
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JB/T 9249-1999: PDF in English (JBT 9249-1999) JB/T 9249-1999
JB
MACHINERY INDUSTRY STANDARD OF
THE PEOPLE’S REPUBLIC OF CHINA
ICS 17.120
N 12
Replacing ZB N12 008-89
Vortex shedding flow transducer
ISSUED ON. AUGUST 6, 1999
IMPLEMENTED ON. JANUARY 1, 2000
Issued by. State Bureau of Machine Building Industry
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative references ... 4
3 Definitions ... 5
4 Product category ... 6
5 Technical requirements ... 9
6 Test methods ... 12
7 Inspection rules ... 18
8 Mark, packaging and storage ... 19
Foreword
This Standard is the revision of ZB N12 008-89 “Vortex shedding flow
transducer”.
There is no main technical differences between this Standard and ZB N12 008-
89. Only editorial changes are made on the basis of the previous standard.
From the implementation date of this Standard, ZB N12 008-89 is replaced by
this Standard.
This Standard was proposed by and shall be centralized by National Industrial
Process Measurement and Control Standardization Technical Committee.
The drafting organization of this Standard. Shanghai Institute of Process
Automation Instrumentation.
Vortex shedding flow transducer
1 Scope
This Standard specifies the definition, product category, technical requirements,
test methods and inspection rules of vortex shedding flow transducer.
This Standard is applicable to liquid and gas vortex shedding flow transducers
with pulse signal output (hereinafter referred to as the transducer). It is also
applicable to the transducer of vortex shedding flow transmitter with
standardized signal output as well as the transducer of vortex shedding
flowmeter with flow display.
2 Normative references
The following standards contain the provisions which, through reference in this
Standard, constitute the provisions of this Standard. At the publication of this
Standard, the editions indicated are valid. All standards shall be revised. The
parties who use this Standard shall explore the possibility of using the latest
version of the following standards.
GB 191-1990 Packaging - Pictorial marking for handling of goods
GB/T 2555-1981 Pipe flange connectors for ordinary use - Mounting
dimensions
GB/T 2556-1981 Pipe flanges for ordinary use - Sealing surfaces - Forms
and dimensions
GB 3836.1-1983 Electrical apparatus for explosive atmosphere - General
requirements
GB 3836.2-1983 Electrical apparatus for explosive atmosphere - Flameproof
electrical apparatus “d”
GB 3836.3-1983 Electrical apparatus for explosive atmosphere - Increased
safety electrical apparatus “e”
GB 3836.4-1983 Electrical apparatus for explosive atmospheres -
Intrinsically safe circuits and electrical apparatus “i”
GB/T 9248-1988 Methods of evaluating the performance of flowmeters for
incompressible fluids
GB/T 15464-1995 General-purpose specification for the packaging
instrumentation products
JB/T 9329-1999 Basic environmental conditions and testing methods for
instruments transportation and storage in the transportation
3 Definitions
This Standard uses the following definitions.
3.1 Vortex shedding flow transducer
Flow transducer that adopts placing an un-streamlined vortex body in fluid. The
fluid alternatively separates and releases two strings of vortex on both sides of
the vortex body, which are regularly and crisscross lined. Within a certain range,
vortex’s separation frequency is proportional to the flow. And the vortex
frequency can be detected by various types of detectors.
It comprises of housing, vortex body, detecting element and amplifier.
3.2 Amplifier
The device that amplifies and reforms the signal output by detecting element.
3.3 Meter factor
The number of pulses output from per unit volume of fluid through the sensor.
3.4 Mean meter factor
The arithmetic mean value of the maximum value and the minimum value
among meter factors of each measurement point, within the predetermined flow
range, represented by K .
3.5 Resistance factor
Factor relating to pressure loss when the fluid goes through the transducer,
represented by Cd.
3.6 Linearity
The degree of consistency between calibration curve and stipulated line, i.e.,
the ratio BETWEEN the half value of the maximum value and the minimum
value AND the average meter factor, represented by percentage.
Gas. air under 20°C and 101325Pa.
4.2.5 Range
The transducer’s range shall be selected from the following numeral systems.
6, 7, 8, 10, 11, 12, 15, 20, 25, 30.
4.2.6 Measured mediums
The measured mediums shall comply with the requirements in Table 2.
Table 2
Measured medium Gas-liquid universal Liquid Gas
Mark number 1 2 3
4.2.7 Temperature range
The transducer’s range of working temperature shall be selected among the
following numeral systems of upper temperature limit and lower temperature
limit.
Upper temperature limit. 50, 80, 120, 200, 250, 300, 400°C;
Lower temperature limit. 0, -10, -20, -40, -80, -120, -200°C.
Thermal vortex shedding flow transducer’s absolute value of the difference
between the upper limit and the lower limit temperature shall be greater than
50°C.
4.2.8 Power supply
The transducer’s power supply shall use AC power supply of which the
frequency is 50 HZ; the root-mean-square voltage is 220 V. It may also use DC
power supply.
DC power supply voltage shall be selected from the following numeral systems.
12, 24, (36) V.
Note. Values in brackets are not recommended to use.
4.2.9 Output signal
The transducer’s output signal is pulse signal, in which.
Voltage pulse. low level 2V; high level 6V.
Current pulse. low level is 4mA±0.25mA; high level is 20mA±1mA.
resistance coefficient shall not be greater than 2.4.
5.6 Compressive strength
The transducer shall be able to withstand the compressive strength test of 1.5
times nominal pressure and 5 min. There shall be no damage nor leakage.
5.7 Power supply voltage variation
When power supply voltage varies between -15% ~ +10% of nominal value, the
deviation BETWEEN meter factors of the transducer’s all measurements points
AND the original calibrated average meter factor of this transducer shall be
within the permissible basic error limit range, and comply with the requirements
of 5.2, 5.3 and 5.4.
5.8 Power supply frequency variation
When power supply frequency varies between -5% ~ +5% of rated value, the
deviation BETWEEN meter factors of the transducer’s all measurements points
AND the original calibrated average meter factor of this transducer shall be
within the permissible basic error limit range, and comply with the requirements
of 5.2, 5.3 and 5.4. (This article is only applicable to AC power supply
transducer.)
5.9 Output signal
When the transducer’s loading resistance varies within the range specified by
the manufacturer, the level value of pulse signal shall comply with the
requirements of 4.2.9.
5.10 Insulation resistance
The insulation resistance among the transducer’s power supply terminal, output
terminal and housing shall not be less than 20MΩ.
5.11 Insulation strength
5.11.1 DC power supply transducer
Between the transducer’s power supply terminal and housing, between output
terminal and housing, it shall withstand the insulation strength test of which the
frequency is 50Hz, the voltage is 500V and the time is 1min. There shall be no
breakdown or arcing.
5.11.2 AC power supply transducer
Between the transducer’s power supply terminal and housing, between output
terminal and housing, it shall withstand the insulation strength test of which the
frequency is 50Hz, the voltage is respectively 1500V and 500V, and the time is
1min. There shall be no breakdown or arcing.
5.12 Effect of external magnetic field
Under the effect of external magnetic field of which the frequency is 50Hz, and
the magnetic field intensity is 400A/m, the deviation BETWEEN meter factors
of the transducer’s all measurements points AND the original calibrated
average meter factor of this transducer shall be within the permissible basic
error limit range, and comply with the requirements of 5.2, 5.3 and 5.4.
5.13 Appearance
The outer surface of the transducer shall be well treated. There shall be no
peeling, flaking or other defects on the outer surface coating; no damage on the
sealing surface; no loosening fasteners. All visible writings and symbols shall
be clear.
5.14 Anti-transport environmental performance
The transducer shall comply with the requirements in JB/T 9329 under the
conditions of transport packaging. After the test, the deviation BETWEEN meter
factors of the transducer’s all measurements points AND the original calibrated
average meter factor of this transducer shall be within the permissible basic
error limit range, and comply with the requirements of 5.2, 5.3, 5.4 and 5.6. The
high temperature uses +55°C, the low temperature uses -40°C, falling shall be
free fall and its height shall be 100mm.
5.15 Explosion-proof performance
Explosion-proof performance of the explosion-proof transducer shall comply
...
...... Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.
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