The Yoshitake GP-1000 Series pilot-operated pressure reducing valves for steam can be used with confidence for small to large flow rates in a host of applications ranging from building utilities systems, air-conditioning systems, and factory systems. The spherical main valve offers great sealability and a significant reduction in valve seat leakage (compliant with ANSI Class IV). It features a simple and robust internal structure and complies with SHASE-S106 standard for pressure reducing valves.

Features

1. Significantly improved workability and durability compared with conventional pressure reducing valves.
2. Spherical main valve offers great sealability and great reduction of valve seat leakage (compliant with ANSI Class IV).
3. Compliant with SHASE-S106 Pressure Reducing Valves (by the Society of Heating, Air-Conditioning and Sanitary Engineers of Japan).
4. Simple and robust internal structure.

Description of GP-1000 Series Model Code

• GP-1000: Standard (JIS 10K FF flanged)
• GP-1010: JIS Rc screwed
• GP-1001: Equipped with a handle
• GP-1002: For low pressure (0.03-0.15 MPa)
• GP-1012: For low pressure, JIS Rc screwed
• Material options:
  • S: Trim parts (piston and cylinder) made of stainless steel
  • SS: Wetted parts made of stainless steel
  • AS: All stainless steel
  • H: High pressure up to 1.6 MPa inlet

Specifications

Model	GP-1000 / 1010	GP-1000SS	GP-1000H	GP-1002 / 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	Steam	Steam	Steam
Inlet pressure	0.1 - 1.0 MPa	0.1 - 1.0 MPa	0.1 - 1.6 MPa	0.1 - 0.5 MPa
Reduced pressure	0.05 - 0.9 MPa	0.05 - 0.9 MPa	0.05 - 0.9 MPa, 0.9 - 1.4 MPa	0.03 - 0.15 MPa
Min. diff. pressure	0.05 MPa	0.05 MPa	0.05 MPa	0.05 MPa
Max. reducing ratio	20:1	20:1	20:1	20:1
Max. temperature	220℃	220℃	220℃	220℃
Valve seat leakage	0.01% or less of rated flow	0.01% or less of rated flow	0.01% or less of rated flow	0.01% or less of rated flow
Body material	Ductile cast iron	Stainless steel	Ductile cast iron	Ductile cast iron
Valve/Seat material	Stainless steel	Stainless steel	Stainless steel	Stainless steel
Piston/Cylinder	Brass or Bronze	Stainless steel	Brass or Bronze	Brass or Bronze

INFO

Reduced pressure must be 90% or less of inlet pressure (gauge pressure).

Dimensions and Weights

GP-1000, 1002 (Flanged)

Size	L (mm)	H1 (mm)	H (mm)	Weight (kg)
15A	150	64	285	8.0
20A	155	64	285	8.5
25A	160	67	300	10.0
32A	190	82	323	14.0
40A	190	82	323	14.5
50A	220	93	347	20.0
65A	245	100	357	30.0
80A	290	122	404	35.0
100A	330	144	450	52.5

GP-1010, 1012 (Screwed)

Size	d	L (mm)	H1 (mm)	H (mm)	Weight (kg)
15A	Rc 1/2	150	64	285	7.0
20A	Rc 3/4	155	64	285	7.0
25A	Rc 1	160	67	300	8.5
32A	Rc 1-1/4	190	82	323	12.0
40A	Rc 1-1/2	190	82	323	12.5
50A	Rc 2	220	93	347	18.0

Operation

The pressure-reducing valve reduces pressure by 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 the adjusting spring allows the spring to close the main valve and pilot valve. 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 the strainer via the inlet pressure passage to also apply inlet pressure to the downside of the pilot valve.
2. Turning the adjusting screw clockwise compresses the spring, which flexes the diaphragm to open the pilot valve.
3. Inlet pressure via the 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 the main valve spring, to open the main valve. The fluid then begins to flow from the inlet side.
4. Reduced pressure is led to the diaphragm chamber via the reduced pressure sensing port. 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.

Nominal Size Selection Method

Specifications Selection Chart

Find the intersection point of the inlet and reduced pressures. The GP-1000 series valves are suitable within ranges (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)

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%

Characteristics Chart

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)

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.

Nominal Size Selection Chart

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.

Nominal Size Selection Calculation Formula

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 the chart below, multiply the rated Cv value, and obtain the corrected Cv value.

GP-1000 Flow Rate Table (kg/h)

P1 (MPa)	P2 (MPa)	15A	20A	25A	32A	40A	50A	65A	80A	100A
1.0	0.05	92	212	369	600	831	1478	2310	3326	5913
1.0	0.1-0.4	132	303	528	858	1188	2112	3300	4752	8448
1.0	0.5	127	292	508	826	1145	2035	3180	4580	8142
1.0	0.8	87	200	349	566	785	1396	2181	3142	5585
0.8	0.1-0.3	108	248	432	702	972	1728	2700	3888	6912
0.8	0.5	92	212	370	601	833	1481	2314	3332	5915
0.6	0.1-0.2	84	193	336	546	756	1344	2100	3024	5376
0.6	0.4	67	155	270	439	608	1080	1690	2433	4326
0.4	0.1	60	138	240	390	540	960	1500	2160	3840
0.4	0.2	55	126	220	358	496	883	1380	1987	3532
0.2	0.1	30	70	123	200	277	493	771	1110	1974

INFO

When the inlet pressure is more than 0.7 MPa and the pressure reduction ratio is more than 10:1, calculate the corrected Cv value by multiplying the rated Cv value by the correction factor C.

Installation

Example of Piping

Precautions During Installation

WARNING

Because of heavy weight, hold the valve with lifting equipment while piping. Failure to do so may result in injury due to dropping the valve. In case installing a safety valve as a safety device at the outlet side, joint relief pipe at the outlet of the safety valve and guide it to a safe place where steam can relief out.

1. Do not disassemble the valve unreasonably.
2. Remove foreign matter and scales from the lines before connecting the valve.
3. Install a strainer (80 mesh) at the valve inlet side.
4. Install a safety valve at the valve outlet sides as a safety device for equipment.
5. Install a pressure gauge at both the inlet and outlet sides of the valve.
6. Install a steam trap to the inlet sides of the valve to prevent drainage problems.
7. When installing quick open and close valves, such as a solenoid valve, install it at the inlet side as much as possible, and secure at least 3 m from the valve.
8. When pressure reducing in two stages, secure at least 3 m between the valves.
9. Install the valve in the proper direction of the fluid flow.
10. Do not apply excessive load, torque, or vibration to the valve.
11. Install the valve perpendicularly to horizontal lines.
12. Provide a by-pass line.
13. Provide space on the top and bottom of the valve so that the valve can be easily disassembled and inspected.

Operating Procedure

WARNING

Do not touch the valve directly with bare hands. Before flowing the steam in the pipe line, make sure steam can flow without any danger at the end of the pipe line and the pipe line is connected tightly.

1. Close the stop valve at the 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.
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.

Maintenance Procedure

Troubleshooting

Problem	Cause	Solution
Pressure does not reach the desired value.	1. Incorrect pressure is being used. 2. Strainer is clogged. 3. Foreign matter exists between piston and cylinder. 4. Piston ring is damaged. 5. Nominal size is too small. 6. Pressure is not adjusted correctly. 7. Strainer installed before valve is clogged. 8. Pressure gauge is faulty.	1. Correct the pressure. 2. Disassemble and clean. 3. Remove foreign matter/polish scratches. 4. Replace piston ring. 5. Change nominal size. 6. Readjust pressure. 7. Disassemble and clean. 8. Replace it.
Reduced pressure raises above the specified value.	1. Foreign matter exists between main valve and seat. 2. Foreign matter exists between pilot valve and seat. 3. Foreign matter exists between piston and cylinder. 4. Trap is not provided for dead-end.	1. Remove foreign matter/lap seat. 2. Clean or replace pilot valve assembly. 3. Remove foreign matter/polish scratches. 4. Install a trap.
Abnormal noise is heard.	1. Nominal size is too large. 2. Pressure reducing ratio is too large. 3. Drainage problem is caused. 4. Abrupt OPEN/CLOSE valve is too close.	1. Change nominal size. 2. Reduce pressure in two stages. 3. Install a trap. 4. Allow at least 3 m between valves.

Disassembly

Be sure that the stop valves at the inlet and outlet side of the pressure reducing valve are closed and all internal pressure and condensate have discharged before disassembling the valve.

1. Pilot valve: Loosen the lock nut and turn the adjusting screw to release the spring. Remove the bolt of the spring chamber. Remove the spring chamber, spring, top spring plate, bottom spring plate, and diaphragm. Remove the pilot valve assembly using a ring spanner.
2. Piston: Remove the bolt of the top cover and the top cover. Pick up the spindle, and remove the piston ring and the inner ring.
3. Main valve: Remove the bolt of the bottom cover. Remove the bottom cover, main valve spring, and main valve.

TIP

Replace gaskets with new ones when reassembling. If the gasket is used for a long time, it may cause a steam leakage problem. Assemble in the reverse order of disassembly and tighten the bolts evenly.

Exploded Drawing

• Diaphragm: Replace every 2 years
• Piston ring: Replace every 3 years
• Inner ring: Replace every 3 years
• Pilot valve assembly: Replace every 5 years
• Gaskets: Replace every 2 years
• Strainer: Replace every 5 years