Yoshitake SY-20-20 is a high-flow-rate marine type Y-strainer designed for removing dust, scale, and other foreign matter from water, oil, steam, air, and other non-dangerous fluids. It is mainly used for cooling water and industrial water applications. It features a cast carbon steel body with a JIS 20K RF flanged connection and a stainless steel screen with 80 mesh as standard. The design provides the largest possible filtration area to minimize flow rate decreases caused by clogging.

Features

• High-flow-rate marine type with the largest possible filtration area in view of decrease in flow rate caused by clogging.
• Stainless steel screen with 80 mesh as standard.

Specifications

Specification	Value
Application	Steam, Air, Cold and hot water, Oil, Other non-dangerous fluids
Nominal Size	15A - 250A
Maximum Pressure	2.0 MPa
Maximum Temperature	260℃ (If the temperature is over 260°C, please contact the manufacturer)
Body Material	Cast carbon steel (SCPH2)
Screen Material	Stainless steel (SUS304)
Screen Perforation	φ6-8P (φ6-1.80 holes/cm²)
Screen Mesh	Standard 80 mesh (20 to 60 mesh also available)
Connection	JIS 20K RF flanged

Related Models

The source documentation also covers related models such as SY-20-10 (JIS 10K RF flanged, 1.0 MPa), SY-10-30 (JIS 30K RF flanged, 3.0 MPa), and high-pressure gas approved variants (SY-10H, SY-10HS series). The dimensions and specifications in this page focus on the SY-20-20 model.

Dimensions and Weights

Nominal Size	L (mm)	H1 (mm)	Screen ds (mm)	Screen ls (mm)	d (mm)	Plug	Weight (kg)
15A	160	104	25	56.5	15	R3/8	3.2
20A	160	113	30	67.5	20	R3/8	4.0
25A	180	122	33	75.0	25	R3/8	5.9
32A	240	154	55	101.0	40	R1/2	9.3
40A	240	154	55	101.0	40	R1/2	9.3
50A	260	174	57	114.5	50	R1/2	13.0
65A	275	187	74	124.0	65	R1/2	15.8
80A	360	241	90	167.0	80	R3/4	28.0
100A	362	280	114	187.0	100	R3/4	37.8
125A	415	330	140	224.5	125	R3/4	57.0
150A	520	386	184	308.5	150	R3/4	82.8

Operation and Parts

No.	Name of Parts	Material
1	Body	Cast Steel (SCPH2)
2	Cover	Cast Steel (SCPH2)
3	Screen	Stainless Steel (SUS304)
4	Gasket	Non-Asbestos
5	Stud Bolt	Alloy Steel (SNB7)
6	Nut	Alloy Steel (SNB7)
7	Plug	Carbon Steel (SF490A)
8	Name Plate	Stainless Steel (SUS304)

The screen (3) removes dust, scale, and other foreign matter out of the fluid flowing from the inlet port of the strainer.

Pressure Loss

To use the strainer most effectively, ensure the piping size matches the strainer size. Selecting a smaller strainer size will increase pressure drop and the required equipment entrance pressure might not be maintained.

Standard Flow Velocity (Reference JIS F7101):

• Water, Oil: 2 m/s (2 to 4 m/s)
• Steam: 30 m/s (20 to 40 m/s)

(Screen: Perforated plate φ6.0-1.80 holes/cm², Element 80 mesh)

Installation

Example of Piping

Installation Recommendations

• Install pressure gauges backward and forward of the strainer to check clogging by differential pressure.
• Install the strainer with the cap parts facing downward. However, for steam piping, install with the cap parts facing sideways to minimize condensate accumulation.
• If fluid flows from bottom to top, install a blow valve to remove scale accumulated at the bottom of the riser pipe.

Precautions during Installation

Installation Warnings

• Because of heavy weight, hold the valve with lifting equipment while piping to prevent injury from dropping the valve.
• Confirm if the direction of fluid flow matches the inlet and outlet ports.
• Carry out the securing of pipes properly; excessive piping stress may deform the strainer.
• Do not apply excessive load, torque, or vibration to the valve.
• Reserve adequate maintenance space (Dimension H) for screen cleaning:
  • 15A: 146mm, 20A: 158mm, 25A: 170mm, 32A/40A: 223mm, 50A: 248mm, 65A: 276mm, 80A: 342mm, 100A: 393mm, 125A: 467mm, 150A: 585mm.

Operating and Maintenance Procedure

Operation Warnings

• Prior to letting the fluid run in the system, ensure there is no danger when fluid flows out of the pipe end (risk of scalding or material damage).
• Do not tighten the cap and cover after flowing fluids; the gasket will break and lead to leakage.
• Use the strainer with a maximum pressure loss below 0.1 MPa and clean the screen periodically to prevent damage.

Disassembly and Assembly

1. Completely discharge internal pressure and cool the strainer down before disassembly.
2. Remove the nuts and cover from the body. Extract the screen and clean it with compressed air or cleanser.
3. When re-assembling, clean the gasket contacting surfaces, fit a new gasket, and tighten the nuts evenly in a diagonal pattern. Ensure the apical part of the stud bolt comes out from the flange and nut.

Troubleshooting

Trouble condition	Cause of trouble	Countermeasure and remedy
No fluid flows.	1. Screen is clogged up. 2. Stop valves at inlet and/or outlet side are shut.	1. Disassemble and clean the screen. 2. Open stop valves.
Pressure loss is excessive.	1. Screen is clogged up. 2. Pressure gauge is damaged.	1. Disassemble and clean the screen. 2. Renew the pressure gauge.
Outer leakage occurs	1. Gasket has deteriorated.	1. Replace the gasket.