Yoshitake PD-3 is an air-operated ON-OFF valve designed for a wide range of fluids, applications, and ambient conditions. Featuring a compact design and high durability, this automated control valve utilizes a stainless steel cast body and a metal actuator. It is suitable for steam, air, cold and hot water, oil, and other non-dangerous fluids (600 cSt or less) at temperatures ranging from -30°C to 200°C. The PD-3 is normally closed (pressure to open) and allows for a wide variety of actuators to be used for low pilot pressures, reducing overall costs.

Features

• Compact design and high durability.
• Stainless steel cast body and metal actuator are suitable for a wide range of fluids, applications, and ambient conditions.
• Wide variety of actuators can be used for low pilot pressure.

Specifications

Specification	Value
Application	Steam, Air, Cold and hot water, Oil, Other non-dangerous fluids (600 cSt or less)
Nominal size	15A to 50A
Temperature range	-30 to 200°C (no freeze condition)
Ambient temperature	-15 to 60°C
Installation posture	Any direction is possible
Connection	JIS Rc screwed
Operation	Normally closed (pressure to open) Available with normally open type

Working and Pilot Pressures

• 15A: Working 0-2.2 MPa (Max 1.5 MPa for steam) / Pilot 0.35-1.0 MPa
• 20A: Working 0-1.3 MPa / Pilot 0.45-1.0 MPa
• 25A: Working 0-0.9 MPa / Pilot 0.57-1.0 MPa OR Working 0-2.2 MPa / Pilot 0.35-1.0 MPa
• 32A: Working 0-1.2 MPa / Pilot 0.35-1.0 MPa
• 40A: Working 0-1.0 MPa / Pilot 0.44-1.0 MPa
• 50A: Working 0-0.75 MPa / Pilot 0.56-1.0 MPa

Dimensions and Weights

Size	d	L (mm)	A (mm)	H (mm)	B (mm)	D (mm)	G	Weight (kg)
15A	Rc 1/2	65	135	130	34.5	62	G 1/8"	1.1
20A	Rc 3/4	75	140	135	34.5	62	G 1/8"	1.2
25A	Rc 1	90	150	140	34.5	62	G 1/8"	1.4
25A (High Press.)	Rc 1	90	190	185	55	96	G 1/4"	3.0
32A	Rc 1-1/4	110	205	200	55	96	G 1/4"	3.3
40A	Rc 1-1/2	120	210	205	55	96	G 1/4"	3.6
50A	Rc 2	150	225	215	55	96	G 1/4"	4.2

Structure and Materials

No.	Parts Name	Material
1	Body	Cast Stainless Steel (SCS14A eq.)
2	Packing case	Cast Stainless Steel (SCS14A eq.)
3	Gasket	Graphite
5	Valve disc	PTFE
20	Bonnet	Brass (Cu Zn 40 Pb 2 / C3771 eq.) + Chrome plating
22	Circlip	Steel nickel plated
23	Piston	Brass (Cu Zn 39 Pb3 / C3603 eq.)
24	Exterior lip seal	FKM
26	Spring for piston	Spring steel
27	Position indicator	PA6

Operation

1. Closing operation (normal state) When pilot pressure is not applied, the valve disc [5] is closed by the power of the spring [26].

2. Opening operation When pilot pressure is applied from the pilot port, pressure is added to the bottom part of the piston [23], overcoming the load of the spring [26] to push up the piston [23] and open the valve disc [5]. The position indicator [27] connected to the piston [23] is pushed up at the same time, allowing the valve opening to be checked visually from the outside.

Installation and Piping

Installation Precautions

• Before installing the product in piping, be sure to remove foreign substances and scale from the piping.
• Check the direction of the product so that the fluid flowing and the arrow marked on the product are in the same direction.
• Connect the product to piping securely so that fluid cannot leak. If using a seal agent, prevent it from commingling into the product.
• Install pipes so that excessive load, torque, or vibration cannot be applied to the product.
• When connecting the product to piping, grasp the hexagonal part of the inlet and outlet sides of the body with a tool. Do not screw the product into piping by grasping the actuator part.

Piping Recommendations

• Be sure to install a strainer (60 mesh or equivalent) at the inlet side of the product.
• Install a stop valve and bypass piping for the product to allow for maintenance and inspection.
• Compressed air supplied to the actuator should be clean and dry air without commingling of water, oil, or foreign substances.

Minimum Maintenance Space

Size	H1 (mm)	L2 (mm)
15A	200	200
20A	210	210
25A	220	220
32A	280	280
40A	290	290
50A	310	310

Maintenance and Troubleshooting

Warning for Operation and Maintenance

• Do not touch the product with bare hands in case of high-temperature fluid to avoid scalds.
• When conducting disassembly or inspection, be sure to discharge the inner pressure of the product, piping, and equipment, and cool down the body of the product until it can be touched by bare hands.

Regular Inspection

• Leakage check (visual check) with conducting open and closing operation: More than once a year
• Leakage check (visual check) from leak detection port: More than once a year
• Leakage check (visual check) from position indicator: More than once a year
• Consumable parts: The Gasket [3] has a rough replacement term of 3 years.

Troubleshooting

Trouble	Cause	Remedy
Fluid does not flow (Valve disc is kept closing and does not open)	Pilot pressure is not supplied or is low.	Check air supply piping and apply specified pilot pressure.
	Sealing defect of outer lip seal [24].	Replace the actuator set.
Fluid keeps flowing, does not stop (Valve disc is kept opening and does not close) or valve leakage	Leakage from stop valve on bypass piping.	Close stop valve or replace it.
	Pilot pressure exists inside the bonnet.	Remove pilot pressure from pilot port.
	Foreign substance is stuck on the seat part between valve disc [5] and body [1].	Clean the seat part.
	Damage on the seat part between valve disc [5] and body [1].	Replace the actuator set (if disc is damaged) or the product (if body seat is damaged).
	Defect of spring [26] inside actuator.	Replace the actuator set.
Fluid leaks from the connection part of packing case [2] and body [1]	Leakage from gasket due to loose packing case [2] or deterioration.	Tighten packing case [2] to specified torque or replace gasket [3].
Fluid leaks from leak detection port or pilot pressure leaks from position indicator	Leakage due to deterioration of O-ring or packing inside the actuator set.	Replace the actuator set.

Disassembly and Reassembly

Disassembly Warning

Be sure not to remove circlip [22]. Failure to follow this notice makes the inner spring [26] fly out and result in injury. To remove or install the actuator set from the body [1], supply pilot pressure to the pilot port to raise the valve disc [5]. Then loosen/tighten the actuator set by grasping the hexagonal part of the packing case [2]. Do not stop pilot pressure during this work.

Recommended Torque for Actuator Set

To install the actuator set on the body, tighten so that appropriate pressure can be applied on the gasket [3] with a torque wrench.

Size	Tightening Torque
15A	60 Nm
20A	90 Nm
25A	120 Nm
32A	150 Nm
40A	190 Nm
50A	230 Nm