Azbil KDP Series User manual

OM2-5220-1100
Dierential Pressure Detectors
(Meter Bodies)
Model KDP/KFDB
User's Manual

NOTICE
While the information in this manual is presented in good faith and
believed to be accurate, Azbil Corporation disclaims any implied
warranty of merchantability or fitness for a particular purpose and
makes no express warranty except as may be stated in its written
agreement with and for its customer.
In no event shall Azbil Corporation be liable to anyone for any
indirect, special or consequential damages. This information and
specications in this document are subject to change without notice.
© 2013 - 2020 Azbil Corporation. All Rights Reserved.

i
Table of Contents
Chapter 1. DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
1-1. GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1-2. MODELS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1-3. INSTRUCTIONS FOR INSTRUMENTS (TRANSMITTERS AND CONTROLLERS) USED IN
CONJUNCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Chapter 2. STRUCTURES OF METER BODIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
2-1. EXTERNAL VIEWS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2-2. STRUCTURES AND OPERATING PRINCIPLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Chapter 3. INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
3-1. GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3-2. BRACKET AND BOLTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3-3. PLACE OF INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3-4. INSTALLATION METHOD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3-5. PRESSURE PIPING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
3-6. ELEVATION AND SUPPRESSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Chapter 4. OPERATION METHOD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4-1. DIFFERENTIAL PRESSURE (FLOW) TRANSMISSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
4-2. LIQUID LEVEL TRANSMISSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Chapter 5. INSPECTION AND MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
5-1. CHECK FOR LEAK FROM PIPING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
5-2. BLOW AND CLEANING OF METER BODY AND PIPING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20

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1
Chapter 1. DESCRIPTION
1-1. GENERAL
The differential pressure detector (meter body) accepts a differential pressure through its high
and low pressure connection ports, converts the differential pressure into a torque force by its
center section to which the high and low pressures are applied through respective diaphragms,
and feeds a torque via its torque tube to a pneumatic transmitter (Model KDP) or a pneumatic
controller (Model KFDB).
Some models of detectors have a flange incorporated with diaphragm for connection of the
high pressure line.
1-2. MODELS
Measured Pressures or Type
of Instrument
Model Numbers of
Instruments Used in
Conjunction
Operator‘s Manual Used
in Conjunction
Standard Type, High/Medium
Differential Pressures
Models KDP11/22
Models KFDB11/22
OM2-5220-1101 (KDP)
OM2-6220-0000 (KFDB)
Standard Type, Low Differential
Pressures
Model KDP33
Model KFDB33
Standard Type, Very Low
Differential Pressures
Model KDP44
Model KFDB44
Flange Type Models KDP61/62
Models KFDB61/62
Remote-sealed diaphragm Type Models KDP71/72
Models KFDB71/72
High Working Pressure Type Models KDP81/82
Models KFDBSl/82
1-3. INSTRUCTIONS FOR INSTRUMENTS ( TRANSMITTERS AND CONTROLLERS )
USED IN CONJUNCTION
For the instructions for instruments used in conjunction, refer to respective Operator‘s
Manuals which cover the operating principles, service and unit replacement procedures, and
calibration and adjustment procedures of these instruments.

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Chapter 2. STRUCTURES OF METER BODIES
2-1. EXTERNAL VIEWS
Although external views of meter bodies differ by models as shown in Fig. 2-1, the bracket
mounting section and instrument connection section are identical for models 11/22, 71/72,
and for models 33/44, 81/82.
Fig. 2-1. External Views of Meter Bodies

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2-2. STRUCTURES AND OPERATING PRINCIPLES
The structures and operating principles of the meter bodies are covered in this section.
2-2-1. Models 11/12, 33, and 81/82
(a) The high and low process pressures (HP and LP) are fed via diaphragms (1) and (2) to
the center section (oil filled section) of the meter body. The HP acts on the differential
pressure detecting bellows from the right hand side (3) and the LP from the left hand side
(4). When in the equilibrium state (zero differential pressure state), identical forces are
exercised on both sides of the differential pressure detecting bellows (5).
(b) As the pressure of the HP side rises thereby increasing the differential pressure, the
differential pressure detecting bellows moves leftward. The movement of the bellows is fed
as a torque via the torque arm to the beam of the transmitter.
1 HP SEAL DIAPHRAGM
2 LP SEAL DIAPHRAGM
3 LIQUID FILL OF HP SIDE
4 LIQUID FILL OF LP SlUE
5 DIFFERENTIAL PRESSURE DETECTING BELLOWS
6 DAMPING CONTROL (OPTIONAL)
7 TORQUE ARM
8 TORQUE TUBE
Fig. 2-2. Operating Principle of Meter Body

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2-2-2. Model 44
(a) The high and low process pressures (HP and LP) are fed via the diaphragms and supports
(1) to the center section (silicone filled section) (2) of the meter body. The HP acts on
the pressure detecting diaphragm from the right hand side and the LP from the left hand
side. When in the equilibrium state (zero differential pressure state), identical forces are
exercised on both sides of the differential pressure detecting diaphragm.
(b) As the pressure of the HP side rises, the support moves leftward. The liquid fill flows
through the damping control (3). The movement of the diaphragm is fed as a torque via
the torque arm (4) to the beam of the transmitter.
1 DIAPHRAGM AND SUPPORT
2 LIQUID FILL
3 DAMPING CONTROL
4 TORQUE ARM
5 TORQUE TUBE
Fig. 2-3. Operating Principle of Meter Body

5
2-2-3. Models 61/62
(a) The high and low process pressures (HP and LP) are fed via diaphragms (2) and (11)
to the center section (silicone filled section) of the meter body. A pressure which is
proportional to the liquid head in the process vessel is fed via the seal diaphragm (2) and
liquid fill to the bellows (5) at the center section of the meter body.
(b) The bellows (5) moves in proportion to the liquid head pressure. The movement of
the bellows is fed as a torque via the plunger (6) and torque arm (7) to the beam of the
transmitter.
1 PROCESS CONNECTION FLANGE
2 SEAL DIAPHRAGM
3 DAMPING CONTROL (OPTIONAL)
4 HP LIQUID FILL (SILICONE)
5 BELLOWS
6 PLUNGER
7 TORQUE ARM
8 TORQUE TUBE
9 OVERLOAD SEAL
10 LP LIQUID FILL (SILICONE)
11 SEAL DIAPHRAGM
12 CENTER BODY
13 LP COVER
Fig. 2-4. Operating Principle of Meter Body

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2-2-4. Models 71/72
(a) The high and low process pressures (HP and LP) are fed via diaphragms (2) to the
center section (silicone filled section) (11) of the meter body. The HP is fed via the seal
diaphragm (2) and liquid fill (4) to the bellows (5) at the center section of the meter body.
The LP is fed bia the seal diaphragm (2) and liquid fill (10) to the bellows (5).
(b) The bellows (5) moves in proportion to the differential pressure between HP and LP.
The movement of the bellows is fed as a torque via the torque rod (8) to the beam of the
transmitter.
1 PROCESS CONNECTION FLANGE
2 SEAL DIAPHRAGM
3 DAMPING CONTROL
4 HP LIQUID FILL (SILICONE)
5 BELLOWS
6 PLUNGER
7 TORQUE ARM
8 TORQUE ROD
9 OVERLOAD SEAL
10 LP LIQUID FILL (SILICONE)
11 CENTER BODY
Fig. 2-5. Operating Principle of Meter Body

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Chapter 3. INSTALLATION
3-1. GENERAL
The meter body (detector), together with the instrument (transmitter) coupled to it, can be
installed on a 50 mm pipe stanchion by using the accessory bracket and U-shape bolt.
Model 61/62 meter body can be installed simply by fixing its flange to the process.
3-2. BRACKET AND BOLTS
There are two types of mounting brackets. The bracket and bolts for installation are supplied
accompanying each meter body.
Fig. 3-1. Mounting Brackets
3-3. PLACE OF INSTALLATION
When selecting a place of installation for the instrument, take into consideration the matters
related to instrument inspection, maintenance, longevity, and operation safety as follows:
(1) Select a place where temperature change is small (within the limits of -30 °C to +80 °C).
Avoid a place where the instrument is exposed to high temperature by radiation from a
source of heat.
When water is measured, pay attention to freezing which may cause damage to the meter
body. Provide appropriate means to guard against freezing.
(2) Select a place where is reasonably free from humidity and vibration.
(3) Be sure to provide spaces for inserting a screwdriver for adjustment and span change.

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3-4. INSTALLATION METHOD
Install the meter body in such attitude that its diaphragm or bellows planes are made vertical.
3-4-1. Installation of Regular-type Meter Body
The meter body, together with the transmitter coupled to it, can be installed in either one of
the following methods:
• Pipe stanchion mount
• Process pipe mount
In either case, fix the meter body to a 50 mm vertical or horizontal pipe using the mounting
bracket and U-shape bolt. Fix the pipe securely to a foundation so that the pipe does not sway.
(See Fig. 3-3)
To install the meter body on a process pipe line, prepare brackets for mounting the 50 mm
pipe to the process pipe. (See Fig. 3-2)
When installing a remote-sealed type of meter body, exercise care not to sharply bend or twist
the capillary tube and not to damage the diaphragm.
Fig. 3-2. Example of Line Mount Bracket
Note: When installing the transmitter (meter body) on a 50 mm pipe, note that the order of
mountings (transmitter, bracket, and 50 mm pipe) differs depending on the mounting
direction.
Fig. 3-3. Installation Examples

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3-4-2. Installation of Model 61/62/71/72
Connect the detector flange to a process flange*. Tighten the bolts uniformly. The center of the
flange represents the zero point of the liquid level. (See Fig. 3-5) If the zero point is raised, the
head increases by a corresponding amount.
* Flange gaskets are to be prepared by customer.
When using a semi metallic gasket or a rubber gasket, select an one whose shape is
such that it with not be brought contact with the detector diaphragm (95 mm dia.).
Fig. 3-4. Connection to Process Vessel
3-4-3. Mounting Attitude
When the meter body is incorporated with a vent provision, install it in such attitude that vent
can be fully done. Entrapped drain and other foreign matter remaining in the meter body will
adversely affect measurement.
It is ideal to install the meter body so that its diaphragm or bellows planes are made vertical.
After installation is over, perform ZERO adjustment*.
* Refer to the section for calibration.
When a diaphragm pressure receiver type of meter body (Models 61/62, 71/72) is used for
liquid level measurement, the zero point will be as shown in Fig. 3-5. Calculate the output
referring to the dimensions and calibrate the instrument accordingly.

10
Fig. 3-5. Zero Point of Diaphragm
Note: For the portion from the minimum liquid level (0 % level) to a height of 25 mm, the
output is not linearly proportional to the liquid level.
3-5. PRESSURE PIPING
3-5-1. Models 11/22/33/44/81/82
(1) Piping method (tapping pressure connection method) may differ depending on the
installation position of the instrument and the conditions of the process pipe line. In
general, a manifold piping method or a manifold valve method is used. (The manifold
valve is available as an option.)
Fig. 3-6. Manifold Valve

11
(2) When in flow measurement and the meter body is installed lower than the pipe line, it is
recommended to provide blow pipes.
Fig. 3-7. Blow Piping
(3) For the pressure connection piping from the pressure tap position to the transmitter,
provide a gradient so that drain is returned through the tapping position to the process
line.
(4) Regarding the process pressure connection ports of the meter body, the high pressure side
(HP) is located to the right and the low pressure side (LP) to the left as viewed from the
front of the meter body (transmitter).
If the high pressure side and low pressure side are required to be used in the reverse from
the viewpoint of piping, use a Reverse Unit*.
* The Reverser Unit is available as an option. This unit cannot be used for Model 81/82.
(5) For the pipes for pressure tapping from the process pipe, use pressure pipes of appropriate
schedule number and nominal thickness. A typical example in 1/2-inch Schedule 80 steel
pipe. For measurement of water or steam, copper pipes are used in general.
Examples of pressure piping are shown in Fig. 3-8.

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Fig. 3-8. Pressure Piping for Flow Measurement
(6) To change connections to process:
If it is required to change process connections (vent and drain) between upper and lower
positions, remove the two flanges of the connection ports and also the plugs of vent and
drain, and change the positions between upper and lower. (Refer to the overall dimension
drawings.)
(7) Pressure tapping methods:
For tapping methods of process pressures, refer to the illustrations given in this section.
The "H" is the high pressure side of the meter body and the "L" is the low pressure side.
They are marked on the meter body.

13
Fig. 3-9. Connections of Pressure Pipes for Liquid Level Measurement
The liquid level corresponding to the difference between the 0 % level and the center of
the meter body is given from the beginning. In the case of A or B shown in Fig. 3-9, make
compensation (provide an elevation) for the corresponding amount and set the output at 0.2 to
1.0 kgf/cm2for liquid level 0 to 100 %. In the case of C, a pressure corresponding to the head
of the seal liquid is applied to the low pressure side to the state of A or B and consequently the
high/low relationship between the H side and L side of the meter body is in the reverse.
Therefore, compensation (suppression) should be made for the seal liquid head for the
difference between 100 % level position and 0 % level position.
For "elevation" and "suppression", refer to Section 3-6.
3-5-2. Connection of Flange Type Meter Body to Process
Fig. 3-10. Process Connections of Model 61/62 for Liquid Level Measurement

14
Fig. 3-11. Process Connections of Model 71/72 for Liquid Level Measurement
Fig. 3-12. Pressure Tapping for Model 71/72 for Flow Measurement
(1) Fix the flanges of the meter body to those of the process side by using gaskets and bolts.
Be sure to uniformly and securely tighten the bolts in order to prevent leak.
Lay the capillary tubes in such manner that they are less subjected to large temperature
change. Fix them so that they do not move.

15
(2) Regarding the flange of the low pressure side when in level measurement of an open
tank, fix it securely at a position where it will be less subjected to temperature change
and mechanical vibration. Position the LP side flange at a height lower than that of the
minimum liquid level.
Regarding the seal diaphragm, protect it so that it is not damaged and pay attention so
that no drain is entrapped on it and no dust is collected on it.
(3) For flow measurement, tapping for the differential pressure must be done in the "pipe tap"
system. Therefore, locate the high-pressure-side tap at a location of 2.5D (D denotes the
inside diameter of the process pipe) from the upstream side of the orifice and locate the
low-pressure-side tap at a location of 8D from the downstream side of the orifice.
The tapping connection is of a 3-inch flange connection type. The flanges of the extension seal
type of meter body can be directly used as the tapping flanges.
3-6. ELEVATION AND SUPPRESSION
3-6-1. Definitions of Elevation and Suppression
The terms "elevation" and "suppression" as used inthis publication are defined as follows:
Elevation: Synonymous with "suppressed zero range"
An input range whose low end value is higher than zero.
For example, a range of 20 to 100.
Suppression: Synonymous with "elevated zero range"
An input range whose low end value is lower than zero.
For example, a range of -20 to 0.
3-6-2. Setting of Elevation/Suppression
For setting of elevation/suppression, refer to Section "CALIBRATION AND ADJUSTMENT"
of Operator's Manual for Pneumatic Transmitter OM2-522-000.
Note: The specific-gravity of the liquid fill of Models 71/72 is 0.935 at 20 °C. (For temperature
compensation, use a factor of 0.001/°C)
Fig. 3-13. Elevation and Suppression

16
Open Tank Closed tank (without seal
liquid)
Close tank (with seal liquid)
11, 22,
33, 44,
81, 82
Provide suppression corresponding to differential level between
zero liquid level and center of pressure receiver multiplied by
specific-gravity of liquid measured.
Provide suppression by amount
corresponding to measuring liquid
level multiplied by specific-gravity of
measured liquid (seal liquid).
Subtract from suppression the
difference between zero liquid level
and center position of diaphragm as
elevation.
A
61, 62 No elevation/suppression is needed if the imaginary zero liquid
level* conforms with center position of diaphragm of flange
connection section.
* Refer to Section 3-4-3
If the zero liquid level is higher than center position of
diaphragm, provide elevation by an amount corresponding to
the height multiplied specific-gravity of liquid measured.
B C
71, 72 Provide elevation by an
amount corresponding to
difference between center
positions of HP and LP flange
diaphragms multiplied by
specific-gravity of seal liquid.
When zero liquid level is
higher than center position
of HP flange diaphragm,
add as elevation an amount
corresponding to the height
multiplied by specific-gravity
of measured liquid.
Provide suppression by an
amount corresponding to
difference between center
position of HP and LP flange
diaphragms multiplied by
specific-gravity of seal liquid.
When zero liquid level is
higher than center position
of HP flange diaphragm,
subtract from the above
suppression an amount
corresponding to the height
multiplied by specific-
gravity of measured liquid as
elevation.
Not applicable
D E