Yoshitake GD-26GS direct type pressure reducing valve is designed for air and other non-dangerous fluids. Constructed with cast stainless steel wetted parts and EPDM seals, it provides reliable pressure control up to 1.0 MPa inlet pressure. The GD-27GS model offers the same performance with flanged connections.

Features

• Stainless steel is used for wetted parts for excellent corrosion resistance.
• Low noise design ensures quiet operation.
• Pressure balance structure can keep the reduced pressure at a constant level without being affected by inlet pressure fluctuations.
• Maintenance and inspection can be conducted easily by disassembling simply from the upper side.
• Compact and lightweight design allows horizontal or vertical installation on piping.
• A strainer (40 mesh) is incorporated in 15A to 50A nominal sizes.

NOTE

For medium including oil, use fluorine rubber (FKM) for the disc and diaphragm. Otherwise, standard EPDM disc and diaphragm may be broken. Please contact the manufacturer when using for gas containing oil.

Specifications

Specification	Details
Model	GD-26GS / GD-27GS
Application	Air, Other non-dangerous fluids
Inlet Pressure	1.0 MPa or less
Reduced Pressure	(A) 0.05-0.35 MPa (B) 0.3-0.7 MPa
Application Temperature	5-90℃
Minimum Differential Pressure	0.05 MPa
Max. Pressure Reduction Ratio	10:1
Body / Valve Seat	Cast stainless steel
Valve Disc / Diaphragm	EPDM
Connection	GD-26GS: JIS Rc screwed GD-27GS: JIS 10K FF flanged

Dimensions and Weights

GD-26GS (JIS Rc screwed)

Nominal Size	d	L (mm)	H (mm)	H1 (mm)	Weight (kg)
20A	Rc 3/4	135	170	41	2.2
25A	Rc 1	135	170	41	2.2
32A	Rc 1-1/4	180	224	57	4.7
40A	Rc 1-1/2	180	224	57	4.5
50A	Rc 2	200	239.5	61	6.5

Characteristics

Pressure Characteristics

This chart shows variation in reduced pressure when the inlet pressure of 0.6 MPa is changed between 0.15 MPa and 1.0 MPa while the reduced pressure is set at 0.1 MPa.

Flow Rate Characteristics

Nominal Size	Pressure Range	Offset Pressure
15-100A	(A) 0.05-0.35 MPa	Within 0.05 MPa
15-100A	(B) 0.3-0.7 MPa	Within 0.10 MPa

Nominal Size Selection

Rated Cv Value Table

Nominal size	15A	20A	25A	32A	40A	50A	65A	80A	100A
Rated Cv value	2	2.3	3.5	6	7	11	21	26	38

Installation and Operation

Piping Example

PRECAUTION

When installing a safety relief valve for equipment protection at the outlet side of the product, connect a blow-off pipe to the outlet side of the safety relief valve, and lead it to a place where there is no risk of physical damage even if fluid blows out.

INSTALLATION TIPS

• Be sure to remove foreign substances and scale from the piping before installation.
• Install a safety relief valve for equipment protection at the outlet side.
• Be sure to install pressure gauges at the inlet and outlet sides of the product.
• If a quick operating valve (such as a solenoid valve) is installed, place it at a distance of at least 3 meters from the product to avoid malfunction or shortened service life.

Maintenance and Troubleshooting

Troubleshooting

Trouble	Cause	Remedy
Reduced pressure does not reach the desired value	1. Working pressure is improper. 2. Nominal size is too small. 3. Strainer is clogged. 4. Pressure adjustment is improper.	1. Correct the working pressure. 2. Replace product with proper nominal size. 3. Clean the strainer. 4. Readjust pressure.
Abnormal pressure rises at the outlet side	1. Foreign substances stuck between disc and valve seat. 2. O-ring or diaphragm is damaged. 3. Leakage from the globe valve of bypass line.	1. Disassemble and remove foreign substances. 2. Replace O-ring / diaphragm. 3. Repair or replace the globe valve.
Abnormal sound	1. Nominal size is too large. 2. Pressure reduction ratio is too large. 3. Quick operating valve is nearby.	1. Replace with proper size. 2. Reduce pressure in two stages. 3. Keep a large distance between valves.

Cross Section