ddtop LGNC User manual

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LGNC
INTEGRAL ORIFICE FLOW METER
Operation Manual
LGNC-DT-JS-1029-2018(A)

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Preface
Thank you for choosing the products of Dandong Top Electronics Instrument (Group) Co., Ltd.
This operation manual provides you with important information about installation, connection and
commissioning as well as maintenance, troubleshooting and storage. Please read it carefully before
installation and commissioning and save it as an integral part of the product near the instrument for
reading at any time.
This manual can be downloaded from www.ddtop.com.
If you do not follow this manual, the protection provided by this instrument may be damaged.
Trademarks, Copyrights and Restrictions Instructions
Dandong Top Electronics Instrument (Group) Co., Ltd.®, Dandong Top Pump Co., Ltd.®, DDTOP®
are registered trademarks of the company.
The performance specifications of this instrument are effective from the date of release, and are
subject to change without notice. Dandong Top Electronics Instrument (Group) Co., Ltd reserves the
right to modify the products described in this manual at any time without prior notice.
Quality Assurance
Dandong Top Electronics Instrument (Group) Co., Ltd guarantees that all products will be free from
defects in materials and manufacturing processes within one year from the date of leaving the
factory.
During the warranty period, if the product is returned due to quality problems, and the claim is
determined to fall within the scope of the warranty after inspection by the manufacturer, Dandong
Top Electronics Instrument (Group) Co., Ltd is responsible for repairing or replacing it for the buyer
(or owner) free of charge.
Dandong Top Electronics Instrument (Group) Co., Ltd is not responsible for the costs caused by
improper use of equipment, labor claims, direct or subsequent damage, and installation and use of
equipment. Except for the special written warranty certificate for certain products, Dandong Top
Electronics Instrument (Group) Co., Ltd does not provide any express or implied quality guarantee.
Quality
Dandong Top Electronics Instrument (Group) Co., Ltd has passed the ISO9001 quality system
certification. The entire production process is strictly implemented in accordance with the scope of
the quality system, providing the strongest guarantee for the quality of products and services.

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CONTENTS
1 Safety Tips.................................................................................................................................................4
1.1 An explosion may cause death or serious injury...............................................................................4
1.2 Process leaks can cause serious injury or death................................................................................4
1.3 Failure to follow the safety installation guidelines may result in death or serious injury. ...4
2 Product Description..................................................................................................................................4
2.1 Product Structure-Figure 1 ......................................................................................................................4
2.2 Operating Principle-Figure 2...................................................................................................................5
2.3 Package...........................................................................................................................................................5
2.4 Lifting Transportation.................................................................................................................................5
2.5 Storage............................................................................................................................................................5
3 Main Executive Standard..........................................................................................................................5
4 Main Features ...........................................................................................................................................5
4.1 Transmitter and flow element integrated installation, saving installation and maintenance
work.........................................................................................................................................................................5
4.2 Integral orifice plate has an internally polished straight pipe section with 20 times the pipe
diameter upstream and 10 times the pipe diameter downstream, which achieves a good
rectification effect and reduces uncertainty...............................................................................................6
4.3 High precision, after the actual flow calibration of integral orifice plate flow meter, the
basic error of the flow coefficient can be up to ± 0.5%..........................................................................6
4.4 The tapping body is machined from stainless steel forgings to ensure overall strength and
to minimize possible leakage points. ...........................................................................................................6
5 Outline Dimension Diagram-Figure 2 ....................................................................................................6
图2 Figure 2..............................................................................................................................................6
6 Unpacking and Inspection .......................................................................................................................6
6.1 Precautions for Unpacking Inspection..................................................................................................6
6.2 heck Content................................................................................................................................................. 6
7 Installation.................................................................................................................................................6
7.1 Flow element is butt welded with the on-site pipeline to ensure the welding quality and
suppress no leakage. .........................................................................................................................................6
7.2 Installation Technical Requirements...................................................................................................... 6
8 Requirements for the Use of Integral Orifice Plate................................................................................7
9 Fault Analysis and Troubleshooting........................................................................................................7
10 Disassemble ............................................................................................................................................8
10.1 Warning........................................................................................................................................................8
10.2 Waste Disposal...........................................................................................................................................8

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1 Safety Tips
For safety reasons, it is expressly prohibited to modify or change the product without authorization.
Repair or replacement is only allowed to use the accessories specified by the manufacturer.
1.1 An explosion may cause death or serious injury.
When installing the device in an explosive environment, be sure to comply with applicable local,
national, and international standards, codes, and regulations. Ensure that the equipment is installed
in accordance with intrinsically safe or non-flammable site operating procedures.
1.2 Process leaks can cause serious injury or death.
If the process seal is damaged, the medium may leak at the connection.
1.3 Failure to follow the safety installation guidelines may result in death or serious injury.
The operations described in this manual need to be completed by professionals who have received
professional training and obtained corresponding qualifications or special end-users.
2 Product Description
2.1Product Structure-Figure 1
1. Connecting Flange 2. Front Straight Pipe Section 3. Tapping Body 4. Seal Gasket 5. Integral Orifice
Plate 6. Rear Straight Pipe Section 7. Small Seal Gasket 8. Manifold 9. Differential Pressure
Transmitter
图1Figure 1

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2.2 Operating Principle-Figure 2
Integral orifice flow meter and standard orifice plate are based on the principle of fluid continuity
and Bernoulli's equation of conservation of energy, putting a piece of integral orifice plate into a full
tube of medium in the process pipeline, when the fluid flows through the integral orifice plate flow
meter, the flow beam will be in the flow element to form a local contraction, thereby increasing the
flow rate, low static pressure, so the flow element will produce a pressure drop before and after the
pressure drop, that is, the pressure difference, the greater the flow of the medium, the greater the
pressure difference generated before and after the flow element, through the differential pressure
transmitter can output and the measured fluid flow value as a square relationship between the
standard signal, can be converted into flow value.
Basic Calculation Formula:
或
or
C-- Outflow coefficient dimensionless
ε-- Coefficient of expansion
β-- Throttle diameter ratio
d—mm Throttle orifice diameter mm
ΔP--Pa Differential pressure Pa
ρ-- kg/m3 Density of measured medium kg/m3
2.3 Package
Please send packaging waste to a special recycling agency.
2.4 Lifting Transportation
Please use qualified lifting equipment and lifting straps, and pay attention to safety.
2.5 Storage
Storage temperature -20℃~40℃; storage humidity ≤20%.
3 Main Executive Standard
Comply with GB/T2624-2006, ISO5167-2003, BS1042-1992 and other standards.
4 Main Features
4.1 Transmitter and flow element integrated installation, saving installation and maintenance work.

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4.2 Integral orifice plate has an internally polished straight pipe section with 20 times the pipe
diameter upstream and 10 times the pipe diameter downstream, which achieves a good
rectification effect and reduces uncertainty.
4.3 High precision, after the actual flow calibration of integral orifice plate flow meter, the basic error
of the flow coefficient can be up to ± 0.5%.
4.4 The tapping body is machined from stainless steel forgings to ensure overall strength and to
minimize possible leakage points.
5 Outline Dimension Diagram-Figure 2
The dimensions of D and L in the picture are subject to the actual product.
图2Figure 2
6 Unpacking and Inspection
6.1 Precautions for Unpacking Inspection
Check the quantity and material of each part against the packing list.
6.2 heck Content
Check whether the appearance of the instrument is defective or damaged.
7 Installation
7.1 Flow element is butt welded with the on-site pipeline to ensure the welding quality and
suppress no leakage.
7.2 Installation Technical Requirements
7.2.1 When installing the integral orifice flow meter, pay attention that the direction of the inlet and
outlet is consistent with the direction of the "+" sign on the integral orifice plate.

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Figure 3
7.2.2 The gasket shall not protrude into the inside of the pipe after clamping.
8 Requirements for the Use of Integral Orifice Plate
8.1 The fluid must be filled with round pipes and throttling devices, and flow through the pipes
continuously.
8.2 The fluid must be a Newtonian fluid, which is homogeneous, single-phase in physics and
thermodynamics, or can be considered single-phase; including gas, liquid and steam, etc.
8.3 No phase change occurs when the fluid flows through the flow element.
8.4 The fluid flow rate does not change with time, or changes slowly.
8.5 Before the fluid flows through the flow element, its stream must be parallel to the axis of the
pipeline, and there must be no rotating flow.
8.6 The standard flow element is not suitable for flow measurement of pulsating flow and critical
flow.
9 Fault Analysis and Troubleshooting
Failure Phenomenon
Reason
Method
Differential pressure
transmitter indicates no
change
1. Stop valve is not opened
Open the stop valve
2. Differential pressure
transmitter failure
Check differential pressure
transmitter
The indication value of
the differential pressure
transmitter obviously
deviates from the
1. The installation direction of
the flow element is wrong
Reinstall flow element
2. Differential pressure
transmitter failure
Check differential pressure
transmitter

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indication value of the
gauge
3. The working condition
parameters of the measured
medium are inconsistent
with those used when
designing the flow element
Communicate with the
company after-sales service
4. There are attachments on
the flow element
Clean and replace flow element
Differential pressure
transmitter has no
indication
1. Power supply is not turned
on
Turn on power supply
2. Stop valve is not opened
Open the stop valve
3. Differential pressure
transmitter failure
Check differential pressure
transmitter
Medium leakage at the
flow element
1. Insufficient clamping force
of connector
Refasten the connection
2. Sealing gasket failure
Replace the gasket
10 Disassemble
10.1 Warning
Before disassembling, pay attention to dangerous process conditions, such as pressure, high
temperature, corrosive or toxic media in the container, etc.
10.2 Waste Disposal
Please follow the current regulations in each region for waste disposal.