MIYAWAKI TB7N User manual

TEMPERATURE CONTROL STEAM TRAP
USER'S MANUAL

SAFETY GUIDE
The model TB7N is a bimetal temperature control steam trap that has
superior durability and essentially doesn't allow steam to leak.
In order to get maximum benefit from this product, be sure to read
this manual before installing it.
The following warnings and cautions are shown at appropriate
places in this manual.
WARNING
Failure to observe this type of precaution may
lead to serious injury or death.
CAUTION
Failure to follow this type of precaution can
lead to injury or damage to equipment and
property.
Table of Contents
1 SPECIFICATIONS AND MARKINGS 1
2 CONSTRUCTION DETAILS 2
3 INSTALLATION 3
4 SETTING THE TEMPERATURE 4
5 STROKE CHART 6
6 OPERATION 7
7 MAINTENANCE 8
8 SCALE REMOVAL OPERATION (TYPE TB-SR ONLY) 11
9 TROUBLESHOOTING 13
10 WARRANTY 14
11 SERIAL NUMBER (S. No.) DESIGNATION 15
12 GUIDANCE FOR READING SPECIAL PRODUCT
NAME 16

1
1 SPECIFICATIONS AND MARKINGS
WARNING
Be sure not to use this product at higher pressures than the specified maximum
allowable pressure (PMA) or at temperatures higher than the specified maximum
allowable temperature (TMA).
The following items are displayed on the name label or the side of the product.
Check each item to avoid misuse of the product.
1) Maximum allowable pressure (PMA): 4.0 MPa (580 psig)
*TB7BN-C/ TB7BNF-C/ TB7BNW-C: 0.98 MPa (142 psig)
2) Maximum allowable temperature (TMA): 400 °C (752 °F)
*TB7BN-C/ TB7BNF-C/ TB7BNW-C: 183 °C (361 °F)
*TB7N-SR/ TB7NF-SR/ TB7NW-SR: 230 °C (446 °F)
3) Maximum operating pressure (PMO): 2.1 MPa (305 psig)
*TB7BN-C/ TB7BNF-C/ TB7BNW-C: 0.98 MPa (142 psig)
4) Maximum operating temperature (TMO): 350 °C (662 °F)
*TB7BN-C/ TB7BNF-C/ TB7BNW-C: 183 °C (361 °F)
*TB7N-SR/ TB7NF-SR/ TB7NW-SR: 230 °C (446 °F)
5) Size: 15 mm (1/2”), 20 mm (3/4”), 25 mm (1”)
6) Set temperature: The temperature at which the condensate will be discharged from
the steam trap.
7) Year of production: The two leftmost digits in the four-digit or nine-digit “S. No.” are
the last two digits of the year of production.
8) Flow direction: Shown by an arrow
9) Body material: A105
10) Model: Showing the product model name
 Some pictures and illustrations in this manual are examples of TB7N models. For more details
regarding dimensions and other specifications, please refer to the catalog.
The model TB7N fully complies with the requirements of the European Pressure
Equipment Directive 2014/68/EU. It is classified according to Article 4, Section 3 of the
PED, which does not allow to bear the CE marking.

2
2 CONSTRUCTION DETAILS
1. Body
2. Cover
3. Valve Seat
4. Valve
5. Spring
6. Holder
7.
Bimetal
8. Washer
9. E-Ring
10. Shaft
11. Adjust Bolt
12. Adjust Nut
13. O-Ring
14.
Cover Gasket
15. Cap
16. Cap Gasket
17. Screen
18. Seat Gasket
25. O-Ring
(11)
(12)
(13)
(7)
(6)
(5)
(4)
(3)
(17)
(25)
(10)
(15)
(14)
(18)
(1)
(2)
(16)
(8)
(9)

3
3 INSTALLATION
WARNING
Pay very careful attention when working in hazardous environments. There is a risk
of explosion and the possibility of dangerous gases leaking. Always check whether
the pipeline contains flammable, high pressure or high temperature materials
before starting to work.
 Make sure that isolation valves are installed on both the upstream and downstream
lines.
CAUTION
Before installing the product, open both isolation valves and the bypass valve, if
one exists, to blow out any debris or dirt inside the pipeline. After blowing out the
line, before starting to work, close the isolation valves and allow time for the
temperature to drop to a safe working temperature.
When installing the product, be sure to leave clearance for maintaining it.
1) Remove the dustproof seals covering both connections.
※Products shipped in plastic bags may not have dustproof seals.
2) Check the flow direction indicated on the body.
3) The TB7N can be used for both horizontal and vertical lines. However, be sure not to
install it upside-down in a horizontal line, as it will cause the trap to malfunction.
When installing a TB7N in a horizontal line, be sure to maintain a slight slope to the
line, so that any condensate will flow smoothly to the trap.
4) Open the isolation valve on the upstream line and make sure the product works
normally.
Name Plate
Flow direction is
indicated by an
arrow.
Clearance for
maintenance:
More than 30 mm
Upstream line
Downstream line

4
4 SETTING THE TEMPERATURE
WARNING
Only set the temperature when the body temperature reached room temperature,
before any steam is flowing. Be sure not to set the temperature while the steam is
in operation.
4.1 Set temperature
The set temperature is the temperature at which condensate will be discharged from the
temperature control steam trap. It is set to the temperature specified by the customer when
shipped. If the customer doesn't specify a temperature, it is always set to 100 ºC at a
pressure of 1.0 MPa, as the factory default setting.
4.2 Setting the temperature
1) Remove the cap (15).
2) Hold the adjust
bolt (11) using a screwdriver, and
loosen the adjust nut (12) using a wrench.
3) Screw the adjust bolt (11) slowly clockwise until it
stops. This position is the starting point to set the
temperature.
4) See the stroke chart in Section 5 to find the number of
turns corresponding to the temperature you want.
5) Screw the adjust bolt (11) counterclockwise the
number of turns specified in the chart.
6) Hold the adjust bolt (11) using a screwdriver, and then
lightly tighten the adjust nut (12).
7) Attach the cap (15).
(15)
(11)
(12)

5
4.3 Precautions for setting the temperature
Steam trace
Basically, the set temperature should be the temperature used to control the objects being
heated.
Steam main lines
Basically, use a temperature 20 ºC to 30 ºC lower than the saturated temperature.
Other equipment
Basically, use the factory default setting. (100 °C at 1.0 MPa)
※Please consult us for the proper set temperature.

6
5 STROKE CHART
Set temperature
Operating Pressure (MPa)
Number of Turns
Operating Pressure (psig)

7
6 OPERATION
CAUTION
Before starting operation, open the bypass valve or blow valve completely and blow
off the scale in the piping.
6.1 Operation procedure
1) After blowing off the scale from the piping, close the bypass valve or blow valve.
2) Open the stop valve on the trap outlet side.
3) Open the stop valve on the trap inlet side.
6.2 Stop procedure
1) Close the stop valve on the trap inlet side.
2) Close the stop valve on the trap outlet side.
* When stopping for a long time, completely drain the condensate from the piping and trap
and close the valves before and after the trap.

8
7 MAINTENANCE
WARNING
 Before removing the trap from the pipe or disassembling it, be sure to close the
isolation valves. Then, release the residual pressure from the trap body (make
sure that the pressure in the main body is equal to the atmospheric pressure).
After it has fully cooled down (after the temperature of the main body has
reached ambient temperature), confirm for safe conditions and then begin to
work.
 Even when the isolation valves are closed, there may be residual internal
pressure due to leaks from the isolation valves. Therefore, be very careful.
CAUTION
 When replacing parts, make sure the replacement parts are supplied by
MIYAWAKI.
The performance of steam traps deteriorates gradually over time due to wear, corrosion
or dirt accumulating around the valve and the valve seat. Please conduct periodic
diagnosis of traps in order to keep steam control systems and equipment working well.
7.1 Tools for Diagnosing Steam Traps
 Dr. Trap
Dr. Trap is a sophisticated steam trap management system for diagnosing steam traps
automatically by measuring the vibration and temperature of the steam trap. Survey
results are stored in the testing equipment and transferred to a steam trap analysis
software. The software aggregates and analyses steam trap survey data, identifying
faulty steam traps, providing steam loss and financial loss data, estimating CO2 emissions
corresponding to leaking steam traps and providing many other analyze possibilities to
manage the steam trap population easily.
 Dr. Trap Jr.
Dr. Trap Jr. is an inexpensive and easily to handle steam trap diagnostic system
consisting of an ultrasonic checker, temperature probe and a sophisticated analysis
software. The software allows to determine the condition of a steam trap, to estimate
steam and financial losses and the related CO2 emissions.
For more details, please, check our homepage:
https://www.miyawaki.net/en/products/steam-trap-management-system
or ask our local representative.

9
7.2 Repairs
When a trap fails, it is necessary to clean the internal parts and to replace damaged parts.
Take the failed trap apart following the steps below.
7.2.1 Disassembling the trap
1)
Loosen the cover (2), and remove the adjustment unit including the cap (15), the
adjust bolt (11), the adjust nut (12), the O-ring (13), and the cap gasket (16).
2) Take out the bimetal unit, the holder (6), the valve (4), the spring (5) and the screen
(17) by hand. Be careful not to lose the valve as it is very small.
3) Remove the valve seat (3) using a socket wrench.
After cleaning the trap and replacing damaged parts, reassemble the parts in
reverse order as follows.
7.2.2 Reassembling the trap
1) Insert the seat gasket (18) and screw the valve seat (3) into the body (1).
2) Reinstall the screen (17) and the spring (5) in the body (1).
3) Put the valve (4) in the hole in the holder (6), and place it on the spring (5) so that the
lower end of the holder (6) can be inserted into the hole in the valve seat (3).
4) Insert the bimetal unit (the O-ring (25) side of the shaft (10)) into the hole of the holder
(6).
5) After placing the cover gasket (14) on the body (1), screw the cover (2) onto the body
(1).
Torque table
Parts Tools Across the flats Torque
Cover (2) Torque wrench 50 mm (1.97”) 160 N∙m
Valve seat (3) Torque wrench 17 mm (0.67”) 22 N∙m
Cap (15) Torque wrench 24 mm (0.94”) 33 N∙m
Adjust nut (12) Wrench 14 mm (0.55”) －
* When the adjustment unit had been disassembled, set the temperature again after reassembling
it. Follow the steps shown in Section 4, “Setting the temperature”.
When reassembling, be sure to replace the О-ring (13) with a new one. Attach the cover (2) with the
adjustment part to the body (1) after screwing out the adjust bolt (11) by 7 mm or more from the top
of the cover (2).

10
1. Body
2. Cover
3. Valve Seat
4. Valve
5. Spring
6. Holder
7. Bimetal
8. Washer
9. E-Ring
10. Shaft
11. Adjust Bolt
12. Adjust Nut
13. O-Ring
14. Cover Gasket
15. Cap
16. Cap Gasket
17. Screen
18. Seat Gasket
25. O-Ring
(15)
Bimetal Unit：
(7),(8),(9),(10),(25)
(12)
(16)
(2)
(14)
(11)
(13)
(17)
(5)
(3)
(18)
(1)
(6)
(4)

11
8 SCALE REMOVAL OPERATION (TYPE TB-SR ONLY*)
WARNING
 Never loosen the gland nut. It is dangerous as steam or condensate will leak out
from the spindle.
CAUTION
 Wear protective equipment, such as protective glasses and work gloves, when
performing the work.
 Exercise caution when you perform the work as high temperature condensate
or steam will leak out from the outlet of the unit when using the handle.
 Although the gland packing is properly tightened at the time of shipment, a leak
may occur from the gland due to stress relaxation. In that case, retighten the
gland nut.
8.1 Necessity of removing scale
In temperature control traps, foreign matter (scale)
in the pipeline adhere to and deposit into the valve
section (especially around the valve port) after long
use, causing a reduction in the discharge flow rate,
clogging, and other abnormalities, which make
normal operation impossible.
Type TB-SR has a function that allows to restore
normal operation by ejecting scale that has
adhered to and been deposited on the valve port to
the outside of the unit, using the handle in the lower
section from the outside*. To maintain the
performance of steam equipment and devices,
perform the following scale removal operation
periodically to restore normal operation.
*Note: When a malfunction is caused by other factors,
normal operation may not be restored by this
operation.
In such cases, please contact the nearest Miyawaki office.

12
8.2 Scale removal operation procedure
1) Wear appropriate protective equipment before you
start the work.
2) Turn the handle (37) anti-clockwise ( ) when
looking from the top of the unit.
Be careful as high temperature condensate or
steam will suddenly leak out from the outlet of
the unit.
3) While paying attention to the outlet of the unit, turn
the handle (37) clockwise ( ) two to three turns.
4) Repeat Steps 2) and 3) two to three times to blow
off the scale that has adhered to the valve port.
5) Turn the handle (37) clockwise lightly ( ) until it
stops. (Pull the spindle (31) all the way down.)
6) Check the surface temperature about one hour
after the above operation. If the indicated
temperature is around the set temperature, the
normal operation of the unit has been restored.
7) If you have any questions, please contact
MIYAWAKI, our local authorized agent, or the
company where you purchased the product.
Part No. Part name
31 Spindle
32 Gland nut
37 Handle
38
Hexagon socket
screw
8.3 Maintenance
 Further tightening the gland nut
When a leak occurs from the gland, retighten the gland nut (32)
slightly.
 Replacing the scale removal unit
If the scale removal device malfunctions, it needs to be
replaced as a complete unit. (Replacement of parts of the unit
is not possible.)
 Torque table
Part Tool Width across
flats Torque
Gland nut (32) Torque wrench 17 mm (0.67”) 20 N∙m
Removal unit Torque wrench 17 mm (0.67”) 25 N∙m
38
37
31
32
Scale
removal
unit
Gasket
(29)

13
9 TROUBLESHOOTING
Problem Possible cause Solution
Steam leaks or blows
through. Dirt is stuck around the valve
(4) or valve seat (3).
Clean the valve (4) and the
valve seat (3).
The valve seat (3) is loose. Tighten the valve seat (3). *1
Damage, erosion or corrosion
of the valve (4) or valve seat
(3).
Replace the valve (4) and the
valve seat (3) as a set.
The seat gasket (18) is
damaged. Replace the seat gasket (18).
The bimetal (7) is damaged. Replace the bimetal unit.
The adjust bolt (11) is backed
out too far. Set the temperature again.
Wrong installation direction Reinstall the product in the
correct direction.
Steam leaks
from the
body.
From the
connection
between the
body and
cover or
between the
body and
cap
The cover (2) is loose. Tighten the cover (2). *2
The cover gasket (14) is
damaged.
Replace the cover gasket
(14).
The O-ring (13) is damaged. Replace the O-ring (13).
Insufficient condensate
discharged, or no
condensate discharged.
The screen (17) is clogged. Clean the screen (17).
Dirt has built up on or around
the valve seat (3). Clean the valve seat (3).
Dirt accumulated in the fluid
passage of the body (1) Clean the body (1).
The bimetal (7) is damaged. Replace the bimetal unit.
The adjust bolt (11) is too
tight. Set the temperature again.
Insufficient condensate
capacity.
Replace the trap with a larger
capacity trap.
*1 and *2: Refer to the torque table in Section 7, “Maintenance” to retighten the parts with
the correct torque.

14
10 WARRANTY
10.1 Warranty period
The warranty period is 18 months after shipment or 12 months after installation, whichever
occurs first.
10.2 Details of the warranty
If the product stops working correctly within the warranty period, we will repair or replace
the product free of charge if the cause of the trouble is not one of the following items.
1) The precautions described in this manual were not observed.
2) User's errors or mistakes such as an inappropriate installation or incorrect handling,
or an excessively large impact caused by dropping
3) Problems caused by devices or equipment other than MIYAWAKI’s, or a disallowed
use environment
4) When a repair or modification has been performed by anyone other than MIYAWAKI
or people who are authorized to make such repairs
5) Intrusion of salt or other substances that promote significant rust or corrosion or
problems from fluids that contain the same substances
6) Consumable parts such as Packing, Gasket, O-ring, Diaphragm, etc.
7) Attachment or accumulation of foreign matter in the pipe, such as dust and scale
8) Problems from fires, natural disasters, or other force majeure which is not
MIYAWAKI’s responsibility
10.3 Warranty limitation
The remedy available under the warranty shall not exceed the sales price of the products
delivered, for any cause whatsoever.

15
11 SERIAL NUMBER (S. No.) DESIGNATION
The following 4-digit or 9-digit ’S.No.' is displayed on the product.
●For 4-digit display
S.No. □□□□
Represents the day.
Represents the month.
Represents the year. (last two digits of the
year according to the Western calendar)
●For 9-digit display
S.No. □□□□□□□□□
MIYAWAKI identification number
Represents the month.
Represents the year. (last two digits of the
year according to the Western calendar)
Month designation system
Month 1 2 3 4 5 6 7 8 9 10 11 12
Symbol 1 2 3 4 5 6 7 8 9 X Y Z
Day designation system
Day 1 2 3 4 5 6 7 8 9 10 11 12
Symbol 1 2 3 4 5 6 7 8 9 A B C
Day 13 14 15 16 17 18 19 20 21 22 23 24
Symbol D E F G H J K L M N O P
Day 25 26 27 28 29 30 31
Symbol Q R S T U V W
Example of serial number designation
1 7 1 1 → Jan.1, 2017
2
9 X
M
→
Oct
.
21, 2029
Example of serial number designation
1 7 1 1 2 C 0 2 0 → Jan., 2017
2 9
X
0 5
M
0 5
0
→
Oct
.
,
2029

16
12 GUIDANCE FOR READING SPECIAL PRODUCT
NAME
〇〇〇-○○-□
Special symbol:
The symbol applies only to
special products
(Please refer to table 1 for details)
Model symbol:
Product model number
Table 1 Symbol description
Suffix Special contents
A Trap for high-pressure gas installed property (only for Gas Trap)
C Blow valve attached
K Change of gasket
L Special face to face dimension
M Change of parts material
P, T Change of operating pressure, temperature, condensate capacity, etc
R Change of screen mesh
V Change of air vent
X Other than mentioned above or complex of special contents above

＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿
© 2020 MIYAWAKI INC.
This user’s manual may not be reproduced or copied in whole or in part, without the
written consent of MIYAWAKI INC.
Some special specifications of the product you have, may found to be different from the
ones in the user's manual. If you have any question, please contact MIYAWAKI, our
local authorized agent, or the company where you purchased the product.
In the interest of the development and improvement of our products, MIYAWAKI Inc.
reserves the right to change the specification of the products without prior notice.
＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿

INTERNATIONAL SALES DEPT.
2-1-30, Tagawakita, Yodogawa-ku, Osaka, 532-0021, Japan
Tel: [phone]
www.miyawaki-inc.com/en e-mail: [email protected]
EU Importer and Authorized representative:
MIYAWAKI GmbH
Birnbaumsmühle 65, 15234 Frankfurt (Oder), Germany
Tel: [phone]
www.miyawaki.de e-mail: [e-mail]
China Importer and Authorized representative:
MIYAWAKI WEST Co., Ltd.
Room 1705, No.1, Building No.311, Yanxin Road, Huishan Economic Development Zone,
Wuxi, Jiangsu, China
Tel: [phone]
www.miyawaki-inc.com.cn e-mail: [email protected]n
808033-07 2112
TB7N