Yoshitake SCV-2 User manual

■EPDT-242■
MODEL SCV-2
CHECK VALVE
PRODUCT MANUAL .
Thank you very much for choosing the Yoshitake’sproduct. To ensure the correct and safe use of the product,
please read this manual before use. This manual shall be kept with care for future references.
The symbols used in this manual have the following meanings.
Warning
This symbol indicates a potentially hazardous situation that, if not avoided,
could result in death or serious injury.
Caution
This symbol indicates a hazardous situation that, if not avoided, may result in
minor or moderate injury or may result in only property damage.
Table of Contents
1. Usage of the Product·················································· 1
2. Specifications···························································· 1
3. Dimensions and Weights············································· 1
4. Pressure loss ·························································· 2
5. Installation
5.1 Precaution for installation······································· 2
6. Operation procedure
6.1 Precaution for operation ········································ 3
7. Maintenance
7.1 Troubleshooting··················································· 3
7.2 Warning for maintenance······································· 3
7.3 Disassembly······················································· 3
7.4 Assembly·······················································3～4
7.5 Exploded view····················································· 4
Warranty Information

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1. Usage of the Product
The SCV-2 check valve prevents backflow of fluid. It is widely used in steam pipelines or cold and hot water
pipelines.
2. Specifications
Model SCV-2
Nominal size 15A, 20A, 25A, 40A, 50A
Application Steam, Cold and hot water
Maximum pressure 1.6 MPa
Applicable temperature 5 to 220 ℃
Connection JIS Rc screwed
Minimum valve opening
pressure 0.003 MPa
* Since a small amount of fluid leaks out of the product, it cannot be used for applications requiring complete
closing.
Caution
Please confirm that the indications on the product correspond with the specifications
of the ordered product model before use.
* If they are different, do not use the product and contact us.
3.Dimensions and Weights
Fig.1 Dimensions and weights
No. Part name
1 Body
2 Cover
3 Disc
4 Retainer A
5 Retainer B
6 Spring
7 Gasket
8 Plate
(mm)
Nominal size Connection d L W B Weight
(kg)
15A JIS Rc 1/2 57 50 34 0.5
20A JIS Rc 3/4 57 50 34 0.45
25A JIS Rc 1 72 69 50 1.1
40A JIS Rc 1 1/2 88 89 67 2.0
50A JIS Rc 2 88 89 67 1.5

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4. Pressure loss
Fluid: water
Fig. 2 Pressure loss chart
5. Installation
5.1 Precaution for installation
Caution
1. Before installing the product in the piping, be sure to remove foreign substances and scale from the piping.
* Failure to follow this notice may prevent the product from functioning properly due to the ingress of foreign
substances and scale into the product.
2. At installation, check the direction of the product so that the fluid flowing and the arrow marked on the
product are in the same direction.
* Wrong direction prevents the product from functioning properly.
3. Connect the product to the piping so that excessive load, torque or vibration cannot be applied to the
product. Be sure to connect the product to piping firmly.
* Failure to follow this notice may cause fluid leakage and result in burns or property damage.
4. When installing the product to steam piping, do not apply seal agent for ambient temperature to screwed
part of pipes (Use seal tape made of fluororesin etc.)
* Use of seal agent for ambient temperature may attach it to valve part and lead to valve leakage.
5. Keeping fluid in the product for a long term fixes sliding parts and leads to malfunction of the product.
6. Fluid with adhesiveness makes the parts stuck and leads to malfunction of the product.
7. Performance value of each Nominal Size Selection Chart is referential value. Since it can change
according to piping condition and usage environment, secure safety factor of 20% or more for performance
value when selecting products.
8. Consider usage condition (usage frequency or durability) when selecting products.
9. Any installation posture (vertical or horizontal) is possible.
10. Installation of rapid open close valve at the outlet side of the product may lead to shorten service life of
the product.
V: Flow rate [L/min]
ΔP: Pressure loss [MPa]

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6.Operating procedure
6.1 Precaution for operation
Warning
Before leading fluid, make sure that there is no danger when the fluid flows to the end of piping.
* If tightening is not secured, hot fluid may spout out and result in burns.
* Fluid outflow may cause property damage.
7.Maintenance
7.1 Troubleshooting
Trouble Cause Remedy
Fluid does not flow.
1.
Contact surface of body [1] and
disc [3] is stuck.
1.
Disassemble and clean
.
2.
Installation direction is wrong.
2.
I
nstall the
product
correctly.
Fluid flows back.
1.
Foreign substance is attached to
contact surface of body [1] and
disc [3]
.
1.
Disassemble and clean.
2.
Contact surface of body [1] and
disc [3] is worn away.
2.
Replace with
new
ones.
3.
Internal parts
are broken.
3.
Replace with
new ones
Outside leakage
1.
Gasket [7] is broken.
1.
Replace the gasket [7].
7.2 Warning for maintenance
Warning
Completely discharge the pressure inside of the product, line and equipment before disassembling or
maintenance. In the case of high-temperature fluid, cool down the product till it can be touched with bare
hands.
* Failure to follow this notice may result in injury or burns.
7.3 Disassembly
1. Remove body [1] and cover [2].
2. Remove retainer B [5] and retainer A [4] in this order (if they are tightly fastened, use tools such as
plier).
3. Remove spring [6] and disc [3] in this order (all the internal parts are removed).
4. Remove the gasket [7] from cover [2].
5. After the disassembly, clean the parts with compressed air or detergent.
7.4 Assembly
Caution
1. At assembly, be sure to replace the gasket [7] with new one.
* Failure to follow this notice may result in leakage, burns or property damage.
2. Clean the contact surface of the gasket [7] for the body [1] and cover [2].
* Poor cleaning may lead to leakage of fluid from the gasket, and result in leakage, burns or property
damage.
3. Connect the parts firmly (pay attention to direction of the disc [3]).
* Failure to follow this notice may lead to deformation or breakage of the parts.

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4. At assembly, see “7.5 Exploded view” and assemble the parts in the reversed order of “7.3
Disassembly”.
Nominal size Torque for tightening cover
15A, 20A 150 N・m
25A 200 N・m
40A, 50A 250 N・m
7.5 Exploded view
Fig. 3 Exploded vie
[1] Body
[3] Disc
[6] Spring
[4] Retainer A
[5] Retainer B
[7] Gasket
[8] Plate
[2] Cover