MIYAWAKI GTH12 User manual

BALL FLOAT STEAM TRAP
USER'S MANUAL

SAFETY GUIDE
The model GTH 12 is a cast steel ball float steam trap with an
integrated bimetal automatic air vent.
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 4
4 MAINTENANCE 5
5 TROUBLESHOOTING 9
6 WARRANTY 10
7 SERIAL NUMBER (S. No.) DESIGNATION 11
8 GUIDANCE FOR READING SPECIAL PRODUCT NAME 12

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 plate or the side of the product.
Check each item to avoid misuse of the product.
(1) Maximum allowable pressure (PMA):
GTH12-5/16/25/32 3.2MPa (464psig)
GTH12-45 5.0MPa (725psig)
(2) Maximum allowable temperature (TMA):
GTH12-5/16/25/32 400°C (752°F)
GTH12-45 425°C (797°F)
(3) Maximum differential pressure (⊿PMX):
GTH12-5 0.5MPa (73psig)
GTH12-16 1.6MPa (230psig)
GTH12-25 2.5MPa (360psig)
GTH12-32 3.2MPa (464psig)
GTH12-45 4.5MPa (652psig)
(4) Maximum operating temperature (TMO):
GTH12-5/16/25/32 400°C (752°F)
GTH12-45 425°C (797°F)
(5) Size: 15mm (1/2"), 20mm (3/4"), 25mm (1")
(6) Serial number: Showing the year and date of production
(7) Flow direction: Shown by an arrow.
(8) Body material: Cast Steel SCPH2
(9) Model symbol: Showing the product model name
Some pictures and illustrations in this manual are that of the representative model of
GTH12 models. For more details regarding a photo of the model GTH12-W, dimensions
and other specifications
, r
efer to the catalog
.
Classification according to PED 2014/68/EU
Fluid group 2 gases
Classification: Category I additionally marked as follows.

2
2 CONSTRUCTION DETAILS
GTH12-5F, GTH12-16F, GTH12-25F, GTH12-32F (Flanged) models
GTH12-5W, GTH12-16W, GTH12-25W, GTH12-32W (Socket Weld) models
1. Body 8. Spring 19. Screen
2. Cover 9. Pin 21. Name Plate
3. Float 10. Bracket 22. Rivet
4. Lever 11. Set Bolt 35. Plug
5. Valve Seat 12. Cover Gasket 36. Plug
6. Seat Gasket 13. Cover Bolt 37. Plug Gasket
7. Valve 17. Air Vent
*The air vent seat gasket (6) and the valve seat gasket (6) are interchangeable.

3
GTH12-45F (Flanged) model
GTH12-45W (Socket Weld) model
1. Body 8. Spring 19. Screen
2. Cover 9. Pin 21. Name Plate
3. Float 10. Bracket 22. Rivet
4. Lever 11. Set Bolt 35. Plug
5. Valve Seat 12. Cover Gasket 36. Plug
6. Seat Gasket 13. Cover Bolt 37. Plug Gasket
7. Valve 17. Air Vent
*The air vent seat gasket (6) and the valve seat gasket (6) are interchangeable.

4
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.
(2) Check the flow direction indicated on the cover.
(3) When installing the model GTH12, install it so that the flow from the upstream line to
the downstream line is horizontal and the top label and the name plate is on the top
side of the body. Install the GTH12 at a pipe that is angling down, so that condensate
flows into the steam trap easily.
 Open the isolation valve on the upstream line slowly and make sure the product works
normally.
Downstream
line
Upstream
line
Installation
position
Clearance for maintenance: More
than
160
mm
Flow direction is
indicated by arrow. Name plate

5
4 MAINTENANCE
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.
4.1 Tools for Diagnosis Steam Traps
 Dr. Trap
It is a diagnostic tool with hardware (diagnostic equipment) that performs automatic
diagnosis at high speed (maximum 10 seconds) and exclusive aggregate analysis
software from the vibration and temperature information of the trap.
Diagnostic information is recorded in the diagnostic equipment and data can be
transferred to the software. As a result, high-speed aggregate analysis, quantitative
grasp of steam leakage and loss amount are possible.
 Dr. Trap Jr.
It is an inexpensive and simple diagnostic tool using hardware (steam trap checker) with
vibration sensor, temperature sensor and exclusive aggregate analysis software.
From the vibration and temperature information of the trap, the judgment such as good
or fail is made by a diagnostician. By inputting the vibration value detected by the steam
trap checker to the aggregate analysis software, it is possible to quantitatively grasp the
amount of steam leakage and money loss.
Caution:
Even if both diagnostic tools are used, accurate diagnosis results may not be obtained
depending on the location and installation status of the steam trap, or the type and
operating condition of the steam trap.
For details, please contact MIYAWAKI, our local authorized agent, or the place where you
purchased.

6
4.2 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.
CAUTION
 Never fail to disassemble the air vent.
To assemble and adjust the air vent is too difficult work. So when cleaning the
air vent, just clean the valve by turning it, or wash it in clear water. After washing
the valve in clear water, if dirt or scale is stuck to valve or is accumulated
around the bimetal, it needs to be replaced with a new air vent.
4.2.1 Disassembling the trap
1) Loosen the 4 cover bolts (13), and remove the body (1).
2) When the pin (9) is removed from the bracket (10), the lever (4) with the float (3) can
be removed. At this time, be careful not to lose the valve (7) or the spring (8).
3) Remove the valve seat (5).
4) When the set bolt (11) is removed, the bracket (10) can be removed.
5) Remove the air vent (17).
6) Clean the internal parts.
7) After disassembling, as the valve and valve seat will break easily, so they must be
handled with care. And remove any rust or scale from the valve and valve seat with
non-woven abrasive agent, fine sandpaper or a clean cloth.
4.2.2 Disassembling the screen
1) Turn the screen (19) counterclockwise and remove it from the cover (2).
 When disassembling, as the screen will break easily, so it must be handled with
care.
2) Clean the screen (19).
Reassemble the parts as follows, reversing the procedure used to disassemble
them.
4.2.3 Replacing the gasket
1) When disassembling, never fail to replace the seat gasket and the cover gasket with
new ones.
2) Before reassembling, never fail to remove any rust or scale from the gasket seat.
3) When reassembling, pay special attention that foreign material such as dirty or scale
is stuck between the gasket and the gasket seat surface.

7
4.2.4 Reassembling the screen
1) After cleaning the screen (19), turn it clockwise and attach it to the cover (2), and
tighten it.
 When tightening, as the screen will break easily, so it must be handled with care.
2) If the screen (19) is damaged, never fail to replace it with a new one.
4.2.5 Reassembling the trap
1) Turn the air vent (17) clockwise and attach it to the cover (2), and tighten it.
2) Reinstall the bracket (10) to the cover (2) so that the hole for the set bolt and the hole
for the valve seat (5) are lined up with the holes in the cover (2).
3) Secure the valve seat (5) to the cover (2). In this case, make sure that the set bolt (11)
and the seat gasket (6) are fitted in the right place.
4) Make sure that the spring (8) and the valve (7) are installed in the correct position in
the lever (4) support section.
5) The bracket (10) should be lined up with the hole for the bracket (10). If you do this,
the pin (9) can be inserted easily and the lever (4) will be reinstalled on the bracket
(10) easily.
6) Reinstall the body (1) to the cover (2) so that the name plate (21) should be on the top
side of the body (1). And then tighten the 4 cover bolts (13).
 Finally, tighten the bolts in a crosswise pattern to avoid uneven tightening.
* The correct torques for the valve seat (5), set bolt (11), cover bolt (13), and air vent (17)
are shown in the following table.
Model Parts Tools Across the flats Torque
GTH12
Valve seat (5) Torque wrench 17 mm (0.67") 25N・m
Set bolt (11) Allen wrench 5 mm (0.20") 11N・m
Air vent (17) Spanner 17 mm (0.67") 22N・m
Screen (19) Pipe wrench - About 30 N・m
Cover plug （36） Torque wrench 23 mm (0.94") 65N・m
GTH12-5, 16,25,32 Cover bolt (13) Torque wrench 19 mm (0.75") 80N・m
GTH12-45 Cover bolt (13) Torque wrench 24 mm (0.94") 110N・m
 Remove any rust and scale from the threaded section and apply the small amount of anti-seizing
agent to it. And then tighten the threaded section with the specified torque.

8
GTH12 model
1. Body 7. Valve 13. Cover Bolt
2. Cover 8. Spring 17. Air Vent
3. Float 9. Pin 19. Screen
4. Lever 10. Bracket 35. Plug
5. Valve Seat 11. Set Bolt 36. Plug
6. Seat Gasket 12. Cover Gasket 37. Plug Gasket
4
1
35
12
3
11
19
17
6
2
13
6
10
9
5
7
8
37
36

9
5 TROUBLESHOOTING
Problem Possible cause Solution
Steam leaks or blows
through.
Foreign
material such as scale
or dirt is stuck between the
valve (7) and the valve seat
(5).
Clean
the valve (7) and the
valve seat (5).
The
valve
(7)
and/or
the
valve
seat (5) are damaged, worn or
corroded.
Replace the valve
unit
.
The float
(3)
is damaged.
Replace the float
(3) and the
lever (4)
The
seat
gasket
(6)
is
damaged.
Replace the
seat
gasket
.
Foreign
material suc
h as scale
or dirt stuck to the inside of air
vent.
Clean
the air
vent (17).
The
seat
ing
surfaces
on
the
valve or the valve seat in the
air vent is damaged, worn or
corroded
Replace the air vent
(17)
with a
new one.
Wrong
installation
position
Change t
he installation so that
the nameplate (21) should face
up.
Wrong
installation direction
Make sure the arrow on the
main body matches the flow
direction of the fluid.
Steam leaks
from the
body.
Between the
body and
body cover
The cover bolts
(13)
are loo
se.
Retighten
the cover bolts
(13).*1
Damage, erosion or
deterioration of the cover
gasket (12)
Replace the cover gasket
(12)
.
The gasket sealing surface on
the body (1) or bottom cover is
damaged.
Replace the body with a new
one, or replace the bottom
cover.
Between the
body and
plug
The plug is loose.
Retighten the plug.*
2
The plug gasket (37) is
damaged.
Replace the plug gasket (37)
with a new one.
Insufficient condensate
discharged, or no
condensate discharged.
The screen
(19)
is clogged.
C
lean the screen
(19)
.
Foreign
material such as a
scale or dirt is stuck around the
valve seat (5).
Clean the valve seat
(5)
.
Dirt has built up in the fluid path
inside the body (1). Clean the body (1).
The floa
t
(3)
is damaged.
Replace the
float
(3)
.
Foreign
material such as a
scale or dirt is stuck to the
inside of air vent (17).
Clean the air
vent
(17).
The air vent
(17)
is damaged.
Replace the air vent
(17).
Insufficient condensate
capacity.
Replace the trap with a larger
capacity trap.
*1 and *2: Refer to the torque table in Section 4, “Maintenance” to retighten the parts to the
correct torque.

10
6 WARRANTY
6.1 Warranty period
The warranty period is 18 months after shipment or 12 months after installation, whichever
occurs first.
6.2 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 ours, or a disallowed use
environment
4) When a repair or modification has been performed by anyone other than us 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 our
responsibility
6.3 Warranty limitation
The remedy available under the warranty shall not exceed the sales price of the products
delivered, for any cause whatsoever.

11
7 SERIAL NUMBER (S. No.) DESIGNATION
S.No. □□□□
Represents the day.
Represents the month.
Represents the year. (last two digits of the
year according to the Western calendar)
Month designation system
Month
Symbol
Month
Symbol
Month
Symbol
Month
Symbol
1
1
4
4
7
7
X
10
2
2
5
5
8
8
Y
11
3
3
6
6
9
9
Z
12
Day designation system
Symbol
Day
Symbol
Day
Symbol
Day
Symbol
Day
1
1
9
9
H
17
Q
25
2
2
A
10
J
18
R
26
3
3
B
11
K
19
S
27
4
4
C
12
L
20
T
28
5
5
D
13
M
21
U
29
6
6
E
14
N
22
V
30
7
7
F
15
O
23
W
31
8
8
G
16
P
24
Example of serial number designation
1 7 1 1 → Jan 1, 2017
2
9X
M
→
Oct
21, 2029

12
8 GUIDANCE FOR READING SPECIAL PRODUCT NAME
〇〇〇-○○-□
Special symbol:
Symbol apply only to special product
(Please refer to table 1 for details)
English letter after “-“
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

For any questions about the product that you purchased or about the details in this user’s
manual, please contact the following.
© 2017 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 place where you purchased.

INTERNATIONAL SALES DEPT.
2-1-30, Tagawakita, Yodogawa-ku, Osaka, 532-0021, Japan
Tel: [phone]
www.miyawaki.net e-mail: [e-mail]
EU Importer and Authorized representative:
MIYAWAKI GmbH
Birnbaumsmühle 65, 15234 Frankfurt (Oder), Germany
Tel: [phone]
www.miyawaki.net 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
808016-04 1912
GTH12