Yoshitake GP-1000 User manual

■EPDT-081a■
Model GP-1000 Series
PRESSURE REDUCING VALVE
Installation & Operation Manual
Please read this bulletin thoroughly before using the pressure reducing valve, so that you may
do so correctly and safely. Please carefully store this bulletin in a handy place.
―――――――――The following safety symbols are used in this manual. ――――――――


Warning


Caution
Contents
1. Features･････････････････････････････････････････････････････ 1
2. Specifications ････････････････････････････････････････････････ 1
3. Dimensions and Weights･････････････････････････････････････ 2
4. Operation････････････････････････････････････････････････････ 3
5. Nominal Size Selection Method
5.1 Specifications selection chart ･････････････････････････････ 4
5.2 Safety valve setting pressure ･････････････････････････････ 4
5.3 Characteristics chart･･････････････････････････････････････ 4
5.4 Nominal size selection chart ･･････････････････････････････ 5
5.5 Nominal size selection calculation formula ････････････････ 6
6. Installation
6.1 Example of piping ････････････････････････････････････････ 6
6.2 Precautions during installation ････････････････････････････ 7
7. Operating Procedure
7.1 Precautions during operation ･････････････････････････････ 8
7.2 Adjustment procedures ･･･････････････････････････････････ 8
8. Maintenance Procedure
8.1 Troubleshooting ･･････････････････････････････････････････ 9
8.2 Precautions during maintenance and inspection ･････････ 10
8.3 Disassembly･････････････････････････････････････････････ 10
8.4 Precautions during reassembly ･･････････････････････････ 11
8.5 Exploded drawing ･･･････････････････････････････････････ 12
After Sale Service
This symbol indicates a potentially hazardous situation that, if not
avoided, could result in death or serious injury.
This symbol indicates a hazardous situation that, if not avoided, may
result in minor or moderate injury. (“Caution” may also be used to
indicate other unsafe practices or risks of property damage.)

■EPDT-081a■
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1. Features
GP-1000 Series pressure reducing valves for steam are pilot-operated valves which can be used with
confidence for small to large flow rate, in a host of applications ranging from building utilities systems,
air-conditioning systems, and factory systems, etc.
2. Specifications
Model GP-1000 GP-1010GP-1000SS GP-1000H GP-1002 GP-1012
Connection Flanged
(JIS 10K FF) JIS Rc Screw Flanged
(JIS 10K FF) Flanged (JIS 16K FF) Flanged (JIS 10K FF) JIS Rc Screw
Nominal size 15～100A 15～50A 15～100A 15～100A 15～100A 15～50A
Application Steam
Inlet pressure 0.1～1.0 MPa 0.1～1.6 MPa 0.1～0.5 MPa
0.05～0.9 MPa
0.05～0.9 MPa
0.9～1.4 MPa
0.03～0.15 MPa
Reduced pressure
90% or less of inlet pressure (gauge pressure)
Min. differential
pressure 0.05 MPa
Max. pressure
reducing ratio 20：1
Max. temperature 220℃
Valve seat leakage 0.01% or less of rated flow
Body Ductile cast iron Stainless steel Ductile cast iron
Valve Stainless steel
Valve seat Stainless steel
Piston/Cylinder Brass or Bronze Stainless steel Brass or Bronze
Material
Gasket Non asbestos
Body hydraulic test 2.0 MPa 3.2 MPa 1.0 MPa
lStainless steel main components (piston & cylinder) are also available.(GP-1□□□S)
lAll stainless steel types are also available for GP-1000.
lAdjusting handle types are also available for GP-1000 and GP-1010.(GP-1001,1011)


Caution
(1) Please collate with attached nameplate and specification of ordered model.
※Please consult factory in case they do not match each other.

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3. Dimensions and Weights
•GP‑1000,1000H,1002
(㎜)
Size ＬＨＨ
１Weight（kg）
15A 150 285 64 8.0
20A 155 285 64 8.5
25A 160 300 67 10.0
32A 190 323 82 14.0
40A 190 323 82 14.5
50A 220 347 93 20.0
65A 245 357 100 30.0
80A 290 404 122 35.0
100A 330 450 144 52.5
•GP‑1010,1012
(㎜)
Size d ＬＨＨ
１Weight（kg）
15A Rc 1/2 150 285 64 7.0
20A Rc 3/4 155 285 64 7.0
25A Rc 1 160 300 67 8.5
32A Rc 1-1/4 190 323 82 12.0
40A Rc 1-1/2 190 323 82 12.5
50A Rc 2 220 347 93 18.0

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4. Operation
No. Parts name
1 Body
5 Diaphragm
8 Adjusting spring
9 Adjusting screw
11 Main valve
12 Main valve seat
13 Main valve spring
14 Piston
15 Cylinder
19 Pilot valve
20 Pilot valve seat
28 Strainer
42 Inlet press. passage
43 Reduced press. Sensing port
44 Diaphragm chamber
The pressure-reducing valve reduces pressure by the throttling the valve. The valve is composed of the
main valve and main valve seat for throttling, and adjusting spring, diaphragm, pilot valve, and piston
for pressure sensing and activation.
(1) When the pressure-reducing valve is mounted correctly, releasing the compression of adjusting
spring [8] allows the spring to close main valve [11] and pilot valve [19]. Slowly open the gate valve
and allow the high-pressure fluid to flow in. Inlet pressure is applied to the downside of the main
valve. High-pressure fluid passes through strainer [28] via inlet pressure passage [42] to also apply
inlet pressure to the downside of the pilot valve.
(2) Turing adjusting screw [9] clockwise compresses the spring, which flexes diaphragm [5] to open the
pilot valve.
(3) Inlet pressure via inlet pressure passage and pilot valve enters the upside of the piston. The pressure
overrides the pressure on the downside of the main valve and the load of main valve spring[13], to
open the main valve. The fluid then begins to flow from the inlet side.
(4) Reduced pressure is led to diaphragm chamber [44] via reduced pressure sensing port [43]. The
diaphragm receives the reduced pressure to be balanced with the adjusting spring load, and control
the pilot valve travel.
(5) The change of pilot valve travel changes the flow rate of fluid to the upside of the piston, and
controls the main valve travel to obtain appropriate reduced pressure.

■EPDT-081a■
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5. Nominal Size Selection Method
5.1 Pressure reducing valve specification selection chart
Find the intersection point of the inlet
and reduced pressures. The GP-1000
series valves are suitable within range
(A), (B), (C), and (D).
・Range（A）：GP-1000H
・Range（B）：GP-1000H、
GP-1000（1010）
・Range（C）：GP-1000H、
GP-1000（1010）、
GP-1002（1012）
・Range（D）：GP-1002（1012）
5.2 Safety valve setting pressure
Reduced pressures (MPa) Safety valve setting pressure (MPa)
0.03～0.1 Reduced pressures＋more than 0.05
0.1～0.4 Reduced pressures＋more than 0.08
0.4～0.6 Reduced pressures＋more than 0.1
0.6～0.8 Reduced pressures＋more than 0.12
0.8～1.4 Reduced pressures＋15％
5.3 Characteristics chart
(1) Flow rate characteristics chart
•Shut-off pressure raise : 0.02 MPa or less
•Offset : 0.03 MPa or less
(Setting pressure: 0.03~0.1 MPa)
: 0.05 MPa or less
(Setting pressure: 0.1~1.4 MPa)
(2) Pressure characteristics chart
Reduced pressure is set to 0.1 MPa
when inlet pressure is 1.0 MPa. The
chart indicates a variation in reduced
pressure when the inlet pressure is
changed from 1.6 to 0.3 MPa.
10050
Offset
Shut‑offpressureraise
5Flowrate
Setting
pressure
(%)0
Reduced pressure
Min.adjustableflowrate Ratedflow

■EPDT-081a■
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5.4 Nominal size selection chart
[Ex.1]
For example, take a pressure reducing valve whose inlet pressure (P1) is 0.6 MPa, reduced pressure (P2)
is 0.4 MPa, flow rate 800 kg/h. First, find the point of intersection (A) of inlet pressure 0.6 MPa and
reduced pressure 0.4 MPa. Vertically proceed from point (A) to come across the flow rate 800 kg/h,
and regard this point as (B). Point (B) is between nominal sizes 40A and 50A. Select the larger nominal
size 50A.
[Ex.2]
For example, take a pressure reducing valve whose inlet pressure (P1) is 0.8 MPa, reduced pressure (P2)
is 0.05 MPa, flow rate 600 kg/h. First, find the point of intersection (C) of inlet pressure 0.8 MPa and
the diagonal line. Move leftward down the diagonal line to intersection point (D) where the diagonals
line intersect with the reduced pressure 0.05 MPa. Vertically proceed from point (D) to come across the
flow rate 600 kg/h, and regard this point as (E). Point (E) is between nominal sizes 32A and 40A.
Select the larger nominal size 40A.

■EPDT-081a■
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P
1
：Inletpressure MPa
1.0
0.7
0.8
0.9
1.6
1.4
1.2
1.1
1.3
1.5
(ロ)(イ)
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0.00 0.05 0.100.15 0.20 0.25 0.30 0.35 0.40
P
2
：Re duced pr essure MPa
C ：Correction coefficient
5.5 Nominal size selection calculation formula
The appropriate nominal size can be calculated by obtaining the Cv value for the operating conditions
in question, as shown below.
•Cv value calculation formula
•Rated Cv value table (When Cv correction coefficient is C=1)
Nominal size 15A 20A 25A 32A 40A 50A 65A 80A 100A
Rated Cv value 1 2.3 4 6.5 9 16 25 36 64
※Correction of rated Cv value
If the inlet pressure exceeds 0.7 MPa, and the pressure reducing is 0.4 MPa or less,
find the appropriate correction coefficient C using chart below, and multiply the rated
Cv value, and obtain the corrected Cv value.
[Ex.]
Take a pressure reducing valve whose inlet
pressure is 0.8 MPa, reduced pressure is 0.05
MPa. Find the inlet and reduced pressure
intersection point (A) at the left chart, then
draw a horizontal line in the leftward
direction to point (B) which indicates a
correction coefficient of 0.85. For a nominal
size of 25A, the corrected Cv value would be
calculated as follows:
4(rated Cv value) ×0.85(correction
coefficient) = 3.4
6. Installation
6.1 Example of piping
W: Max. steam flow rate [kg/h]
P1: Inlet pressure [MPa･A]
P2: Reduced pressure [MPa･A]
ΔP: P1−P2 [MPa]
k: 1+0.0013 ×{super-heated steam
temp.[℃]−saturated steam
temp.[℃]}
2
P
P1
2>
)PP(P138
Wk
Cv 21 +∆ =
2
P
P1
2<
1120P
Wk
Cv =

■EPDT-081a■
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6.2 Precautions during installation


Warning
(1) Because of heavy weight, hold the valve with lifting equipment while piping. Refer to
“3. Dimensions and weights” table for the valve weight.
※Failure to do so may result in injury due to dropping the valve.
(2) In case installing safety valve as safety device at outlet side, joint relief pipe at outlet
of safety valve and guide it to safety place where steam can relief out.
※Failure to do so may result in burns.


Caution
(1) Do not disassemble the valve unreasonably.
※Disassembling the valve at your discretion may affect the original performance.
(2) Remove foreign matter and scales from the lines before connecting the valve.
※Failure to do so may prevent the valve from functioning correctly.
(3) Install a strainer (Recommendation: 100-mesh or close) at the valve inlet side.
※Failure to do so may hamper correct pressure control, which affects the original
performance.
(4) Install a safety valve at the valve outlet sides as safety device for equipment.
※Failure to do so prevents problem identification, resulting in equipment damage.
(5) Install a pressure gauge at both the inlet and outlet sides of the valve.
※Failure to do so may hamper correct pressure adjustment.
(6) Install a steam trap to the inlet sides of the valve to prevent drainage problems.
※Failure to do so may result in drainage problem, affecting the original performance.
(7) When installing quick open and close valves, such as a solenoid valve, install it at
inlet side as much as possible, and secure at least 3 m from the valve.
※Failure to do so may result in malfunction or drastically shortened service life.
(8) When pressure reducing in two stages, secure at least 3 m between the valves.
※Failure to do so may result in malfunction, affecting the original performance.
(9) Install the valve in proper direction of the fluid flow.
※Failure to do so may affect the original performance.
(10) Do not apply excessive load, torque or vibration to the valve.
※Doing so may result in malfunction or drastically shortened service life.
(1) Install the valve perpendicularly to horizontal lines.
(2) Provide the by-pass line. (See 6.1 Example of piping)
(3) When the pressure-reducing ratio is large, install a reducer to keep the flow velocity in the pipe
below 30 m/s or less.
(4) Provide space on the top and bottom of the valve so that the valve can be easily disassembled
and inspected. (See Fig.1)
(mm)
Fig.1
Nominal
size AB
15A
20A 125
25A 315 135
32A
40A 335 155
50A 345 175
65A 355 190
80A 375 225
100A 395 265

■EPDT-081a■
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7. Operating Procedure
7.1 Precautions during operation


Warning
(1) Do not touch the valve directly with bare hands.
※Doing so may result in burns.
(2) Before flow the steam in pipe line, make sure steam can flow without any dangerous at
the end of pipe line and pipe line is connected tightly.
※In case steam blow off, it may result in burns.


Caution
(1)Close the stop valves before and after the pressure reducing valve, and remove all
foreign matter and scales via the by-pass line before operation. And, open each stop
valve slowly.
※Failure to do so may prevent the valve from functioning correctly. And, It may cause
hunting, water hammer, etc., resulting in damage to the valve and other equipment
when the stop valve is opened quickly.
(2)Secondary pressure at by-pass line must be lower than set pressure.
※Safety valve blows in case secondary pressure at by-pass line becomes higher than
set pressure.
(3)When adjusting pressure, slowly turn the adjusting screw
※Incorrect adjustment may cause hunting, water hammer, etc., resulting in damage to
the valve and other equipment.
(4)Remove condensate completely from the line, and close the stop valves before and
after the valve when not using it for long periods of times.
※Rust generated in the valves and lines may cause malfunction.
(5)For the model with handle, be sure to operate the handle manually and turn it while
pushing down.At this time, do not turn with too much torque or do not turn excessively.
※Rust generated in the valves and lines may cause malfunction.
7.2 Adjustment procedures
Follow the steps below, and slowly turn the adjusting screw to set pressure. Incorrect adjustment may
cause hunting, water hammer, etc., resulting in damage to the valve and other equipment.
（1）Close the stop valve at inlet and outlet side of the pressure reducing valve, and taking sufficient
time not to blow the safety valve, blow off the fluid to remove foreign matter via the by-pass line.
After blowing, close the by-pass line stop valve.
（2）Slowly open the stop valve at the inlet side of the pressure reducing valve, and adjust the travel of
the stop valve at the outlet side of the pressure reducing valve so that a little fluid flows.
（3）Loosen the lock nut, and slowly turn the adjusting screw to achieve the desired pressure
(clockwise to increase, counterclockwise to reduce) while observing the pressure gauge on the
outlet side. While adjusting the pressure, push down and turn the handle slowly because the handle
is locked in normal position and look at the secondary side of pressure gauge closely. (Secondary
pressure rises by turning the handle in clockwise and descends in counterclockwise).
（4）Slowly open the stop valve at the outlet of the pressure reducing valve, and readjust the desired
pressure.
（5）After adjustment, tighten the lock nut. For the model with handle, handle is pulled up and locked
by releasing hold. If it is not locked, turn the handle to left and right then release it.

■EPDT-081a■
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8. Maintenance Procedure
8.1 Troubleshooting
Problem Cause Solution
Pressure does not
reach the desired
value.
1．Incorrect pressure is being used.
2．Strainer [28] is clogged.
3．Foreign matter exists between
piston [14] and cylinder [15].
4．Piston ring [16] is damaged.
5．Nominal size is too small for the
specifications.
6．Pressure is not adjusted correctly.
7．Strainer installed before pressure
reducing valve is clogged.
8．Pressure gauge is faulty.
1．Correct the pressure.
2．Disassemble and clean the strainer.
3．Disassemble and remove the foreign
matter. When any scratches are
identified, polish them away using a
paper. Change the parts if scratches
still exist after polishing.
4．Replace the piston ring.
5．Change the nominal size appro-
priately.
6．Observe the adjustment procedures
and readjust pressure.
7．Disassemble and clean it.
8．Replace it.
Reduced pressure
raises above than
the specified value.
1．Foreign matter exists between main
valve [11] and main valve seat
[12], or scratches exist.
2．Foreign matter exists between pilot
valve [19] and pilot valve seat [20],
or scratches exist.
3．Foreign matter exists between piston
[14] and cylinder [15].
4．Trap is not provided for dead-end
line.
5．By-pass valve is leaking.
6．Diaphragm [5] is damaged.
1．Disassemble and remove the foreign
matter. When any scratches are
identified, lap the main valve and
main valve seat. Change the parts if
scratches still exist after lapping.
2．Disassemble the pilot valve as-
sembly, and clean or replace it.
3．Disassemble and remove the foreign
matter. When any scratches are
identified, polish them away using a
paper. Change the parts if scratches
still exist after polishing.
4．Install a trap.
5．Repair or replace it.
6．Replace the diaphragm.
Abnormal noise is
heard.
1．Nominal size is too large for the
specifications.
2．Pressure reducing ratio is too large.
3．Drainage problem is caused.
4．An abrupt OPEN/CLOSE valve is
located too close to the pressure
reducing valve.
5．Outlet pipe is too small.
1．Change the nominal size appro-
priately.
2．Reduce pressure in two stages.
3．Install a trap.
4．Allow as much as possible between
the valves.
5．Select a pipe size that will produce a
flow velocity of 30m/s or less.
lForeign matter and scales in a pipe may cause most of problems of pressure reducing valve. Be
careful sufficiently to foreign matter in a pipe.
lPhenomenon alike valve trouble may happen by fault of pressure gauge, fluid leakage from by-
pass valve, forgetting to close the by-pass valve, clogging strainer, and etc. First, check the said
particulars before above troubleshooting.
lConsult factory when cannot make a judgement whether parts need replacement or not.

■EPDT-081a■
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8.2 Precautions during maintenance and inspection


Warning
(1)Completely discharge internal pressure from the valves, lines, and equipment, and cool
the valve down to a level where you can touch it with bare hands before disassembly
and inspection.
※Failure to do so may result in injury or burns due to residual pressure or spillage
around the valve.


Caution
(1)In order to maintain original performance and function, examine daily and personal
inspection. And, periodical inspection must be examined according to the regulations of
every kind.
※For general users, request to specialized dealer or manufacture.
(2)Pressure reducing valve shall be disassembled and inspected by qualified person or
manufacture.
※Request the treatment to specialized dealer or manufacture in case of any problems.
(3)While disassembly, drain flow out from the valve, so catch it by container. And release
steam completely before disassembling.
※In case of no container for drain, it makes dirty surrounding the valve.
(4)Close the stop valves before and after the pressure reducing valve, and remove all
foreign matter and scales via the by-pass line before operation.
※Failure to do so may prevent the valve from functioning correctly.
(5)When adjusting pressure, slowly turn the adjusting screw.
※Incorrect adjustment may cause hunting, water hammer, etc., resulting in damage to
the valve and other equipment.
(6)Remove condensate completely from the line, and close the stop valves before and
after the valve when not using it for long periods of times.
※Rust generated in the valves and lines may cause malfunction.
(7)In case of no operation for a long period of time, perform operating exam before start
operation again.
※Request the treatment to specialized dealer or manufacture in case of any problems.
8.3 Disassembly
Be sure that the stop valves at inlet and outlet side of pressure reducing valve is closed and all internal
pressure and condensate have discharged before disassembling the valve.
(1) Pilot valve
1．Loosen the lock nut [10] and turn the adjusting screw [9] to release the spring [8] (no
compression). For the model with handle, turn the handle in counterclockwise while pushing
down in order to change the adjusting spring into free position.
2．Remove the bolt [33] of the spring chamber [4]. Remove the spring chamber, spring, top spring
plate [6], bottom spring plate [7], and diaphragm [5]. For the model with handle, remove the
handle and spring chamber by one since they cannot disassemble.
3．Remove the pilot valve assembly [19], [20] using a ring spanner or socket wrench (nominal size
22)
(2) Piston
1．Remove the bolt [34] of the top cover [2] and the top cover. Pick up the spindle [18], and
remove the piston ring [16] and the inner ring [17].
(3) Main valve
1．Remove the bolt [35] of the bottom cover [3]. Remove the bottom cover, main valve spring
[13], and main valve [11].

■EPDT-081a■
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8.4 Precautions during disassembly


Caution
(1) Check that there is no damage and scratches on the main valve, main valve seat, pilot
valve, and pilot valve seat.
※Any scratches at sealing surface lead to increase in secondary pressure. When any
scratches are identified at main valve and seat, polish them away. And, change the
parts if scratches still exist after polishing.Also, in case any scratches are identified at
pilot valve and pilot valve seat, change into pilot valve assembly.
(2) Move the sliding section (pilot valve, piston, etc.) two to three times and confirm they
move smoothly.
※If the sliding parts do not move correctly, it may cause failure problems. (Working not
correctly).
(3) Replace gaskets with new ones when reassembling.
※If the gasket is used for a long time, it may cause steam leakage problem.
(4) Assemble in the reverse order of Disassembly.And tighten the bolts evenly.
※Assemble the valve due to the order. Failure to do so may lead to not assemble
correctly. And if the hexagon bolts are not screwed correctly, it may cause steam
leakage problem.

■EPDT-081a■
-12-
8.5 Exploded drawing
Parts with in the flame are consumable. Please contact us for purchase of these consumable parts.
№Name of parts Replace period
5 Diaphragm 2 years
16 Piston ring 3 years
17 Inner ring 3 years
19・20 Pilot valve assembly 5 years
24 Gasket 5 years
26･27 Gasket 2 years
28 Strainer 5 years
30 Gasket 2 years
Note (*): Apply a liquid sealant for heat and steam resistant (Recommendation: NEVER
SEEZ Standard grade) to the sealing surface of the diaphragm bottom and the top
cover.
Diaphragm [5] and piston ring [16] are used two pieces
for GP-1002 and GP-1012.
The parts from spring
plate to top become as
shown in the following
figure for the model
with handle.