Yoshitake GD-43-20 is a direct-type pressure reducing valve designed for cold and hot water, as well as steam for washing or sterilization. Featuring a cast stainless steel (SCS14A) body and specialized wetted parts, it offers enhanced corrosion resistance and space-saving integration. The closed pressure balance structure keeps reduced pressure constant regardless of inlet pressure fluctuations, and the PTFE-coated diaphragm prevents deterioration while ensuring high durability.

Features

• Space saving and resource saving are achieved, with used materials shown on the body and lower cap for easy recycling.
• Stainless steel (SCS14A and SUS316) is used for wetted parts, improving corrosion resistance.
• PTFE covers the diaphragm contact surface to fluid, making it less liable to deteriorate and highly durable.
• Special fluorine-contained rubber parts are resistant to corrosion.
• Pressure balance structure can keep the reduced pressure at a constant level without being affected by inlet pressure.
• Closed structure keeps fluid from flowing to the outside.
• Can be applied to piping washing, system washing, sterilization washing, and steam for sterilization.

Specifications

Specification	Value
Application	Cold and hot water / Steam for washing or sterilization
Inlet pressure	0.07-2.0 MPa (0.2 MPa or less for steam for washing or sterilization)
Reduced pressure	(A) Yellow spring: 0.02-0.1 MPa (B) Red spring: 0.1-0.25 MPa (C) Black spring: 0.25-0.5 MPa
Minimum differential pressure	0.05 MPa
Maximum pressure reduction ratio	Cold and hot water: 10:1
Fluid temperature	5-90°C (Maximum 130°C for cleaning/sterilizing steam. Allow at least 4 hours between steam flows.)
Body Material	Cast Stainless steel (SCS14A)
Valve disc Material	Special synthetic rubber (special FKM)
Diaphragm Material	Heat-resistant synthetic rubber and PTFE (PTFE applied to wetted face)
Connection	JIS 20K RF flanged

WARNING

• If using for washing steam or sterilization steam, be sure that the maximum temperature is 130°C and avoid continuous use for more than 30 minutes.
• Available with a pressure gauge (JIS Rc 1/8 screwed).

Dimensions and Weights

Dimensions are in mm.

Nominal Size	D	C	g	t	f	n-h	Weight (kg)
15A	95	70	51	14	1	4-15	2.8
20A	100	75	56	16	1	4-15	3.0
25A	125	90	67	16	1	4-19	4.0

Performance Characteristics

Flow Characteristics

Set pressure	Offset
0.2 MPa or less	Within 0.05 MPa
More than 0.2 MPa	Within 0.08 MPa

Pressure Characteristics

This chart shows variation in reduced pressure when the inlet pressure of 0.25 MPa is changed to 2.0 MPa while the reduced pressure is set at 0.20 MPa.

Nominal Sizes Selection (For Cold and Hot Water)

Example: When selecting the nominal size of a pressure reducing valve whose inlet pressure (P1), reduced pressure (P2), and flow rate are 0.5 MPa, 0.3 MPa, and 10 L/min, respectively, trace up vertically from the 0.2 MPa point of differential pressure before and after the valve to find intersection point (a) with the flow rate of 10 L/min. Since intersection point (a) is between nominal sizes 15A and 20A, select the larger one, 20A.

Installation and Operation

Precautions

• When installing a safety valve at the outlet side of the pressure reducing valve, connect a blow-off pipe to the outlet of the safety valve to lead the possible discharged fluid to a safety location.
• Before connecting the pressure reducing valve to the piping, remove foreign materials from the piping. Be sure to install a strainer of 60 mesh or more at the inlet side.
• Be sure to attach a pressure gauge to the inlet and the outlet of the pressure reducing valve.
• When installing a quick opening/closing device (e.g., a solenoid valve), the distance from the pressure reducing valve must be at least 3 m.
• Never touch the pressure reducing valve with bare hands while any hot fluid flows.