Yoshitake GP-1210TS is a pilot-operated, air-loaded pressure reducing valve designed for air and non-corrosive gases. It is a variant of the GP-1210T equipped with stainless steel main components (piston, cylinder, and valve) for improved durability and corrosion resistance. It provides stable pressure control for a variety of applications, ranging from building utility systems to factory air-conditioning and manufacturing systems.

Features

• High Workability and Durability: Far superior to conventional pressure reducing valves.
• Zero Valve Seat Leakage: Free of valve seat leakage with improved workability resulting from the refinement of sliding parts.
• Stainless Steel Trim: Piston, cylinder, and valve are made of stainless steel for enhanced resistance.
• Robust Construction: Simple and robust internal structure.

Specifications

Specification	Value
Application	Air, other non-dangerous fluids
Control Type	Air-loaded type
Inlet Pressure	0.1 – 1.0 MPa
Reduced Pressure	0.05 – 0.9 MPa (90% or less of inlet pressure)
Minimum Differential Pressure	0.05 MPa
Maximum Pressure Reduction Ratio	20:1
Application Temperature	5 – 80°C
Valve Seat Leakage	None
Connection	JIS Rc Screwed

Materials

Part	Material
Body	Ductile cast iron
Valve	Stainless steel
Valve Seat	Stainless steel
Piston, Cylinder	Stainless steel
Diaphragm	Stainless steel

Dimensions and Weights

Nominal Size	d	L (mm)	H1 (mm)	H (mm)	Weight (kg)
15A	Rc 1/2	150	64	220	7.0
20A	Rc 3/4	155	64	220	7.0
25A	Rc 1	160	67	235	8.5
32A	Rc 1-1/4	190	82	258	12.0
40A	Rc 1-1/2	190	82	258	12.5
50A	Rc 2	220	93	282	18.0

Selection Charts

Specifications Selection Chart

Find the intersection point of the inlet and reduced pressures. The valve is suitable within range (A). When within range (B), maximum performance cannot be obtained.

Loading Air Pressure - Set Pressure Chart

The set pressure is basically related to the loading air pressure as shown above. As slight deviations may occur depending on conditions such as air line length, adjust the loading air pressure accordingly.

Flow Characteristic Chart

• Shut-off pressure raise: 0.02 MPa or less
• Offset:
  • 0.03 MPa or less (Setting pressure: 0.05~0.1 MPa)
  • 0.05 MPa or less (Setting pressure: 0.1~0.9 MPa)

Pressure Characteristic Chart

This chart shows variation in reduced pressure when the inlet pressure of 1.0 MPa is changed between 0.3 MPa and 1.0 MPa while the reduced pressure is set at 0.1 MPa.

Nominal Sizes Selection Chart (Fluid: 20°C Air)

Operation

No.	Parts Name	No.	Parts Name
1	Body	15	Cylinder
5	Diaphragm	18	Pilot valve
11	Main valve	19	Pilot valve seat
12	Main valve seat	28	Strainer
14	Piston	44	Diaphragm chamber

(Note: Adjusting spring/screw shown in the diagram apply to the spring-loaded types. GP-1210TS uses air-loaded pressure).

The pressure reducing valve reduces pressure by throttling the valve via the main valve and main valve seat, activated by the pilot valve and piston which sense the air-loaded pressure and the reduced pressure.

1. When the loading air pressure is set to zero, the main valve and pilot valve are closed. High pressure fluid passes through the strainer and applies pressure to the downside of the pilot valve.
2. Increasing the air-loaded pressure flexes the diaphragm to open the pilot valve.
3. Inlet pressure enters the upside of the piston via the pilot valve, overcoming the main valve spring load to open the main valve, allowing fluid to flow.
4. Reduced pressure is led to the diaphragm chamber. The diaphragm balances the reduced pressure with the air-loaded pressure to control pilot valve travel.
5. The pilot valve travel modulates fluid flow to the piston, adjusting the main valve travel to maintain appropriate reduced pressure.

Installation

Installation Warnings

• Because of heavy weight, hold the valve with lifting equipment while piping.
• If installing a safety valve at the outlet side, connect a relief pipe and guide it to a safe location.

::: caution Installation Cautions

• Do not disassemble the valve unreasonably.
• Install a strainer (Recommendation: 80-100 mesh or equivalent) at the valve inlet side.
• Install a pressure gauge at both the inlet and outlet sides.
• Install a steam trap at the inlet side to prevent drainage problems.
• Keep quick open/close valves (e.g., solenoid valves) at the inlet side at least 3 m away.
• When reducing pressure in two stages, secure at least 3 m between valves.
• Do not apply excessive load, torque, or vibration to the valve. :::

Clearances for Air-loaded Type (Dimension B):

• 15A – 20A: 125 mm
• 25A: 135 mm
• 32A – 40A: 155 mm
• 50A: 175 mm (Provide space on the top and bottom of the valve for disassembly and inspection).

Maintenance and Exploded View

Consumable Replacement Periods:

• Diaphragm: 2 years
• O-ring: 3 years
• Pilot valve assembly: 5 years
• Gaskets: 2 - 5 years
• Strainer: 5 years
• Pilot diaphragm: 2 years

Maintenance Safety

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. Confirm the loading air pressure is set to zero.