QuickSelect LoadHolding

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Capacity / Flow Rate Calculator:

Cylinder Applications:

Example #1

1.) Load Holding Valve on the blind end of the cylinder with a load

retracting

the cylinder rod.

* If a 4 port valve is used, a dedicated line should be plumbed immediately
downstream of any object that is causing a backpressure challenge.
* Flow through valve calculated with Area of Cap end of cylinder.
Flow through Cap end equals Flow through Valve.

Flow Rate from 1 to 2

12.10 (GPM) (LPM)

Flow rate into rod end

12.10 (GPM) (LPM)

Example #2

2.) Load Holding Valve on the rod end of the cylinder. With a load

extending

the cylinder rod.

* If a 4 port valve is used, a dedicated line should be plumbed immediately downstream of any object that is causing a backpressure challenge.
*Flow through valve calculated with Area of Rod end of cylinder. Flow through Rod end equals Flow through Valve.

Flow Rate from 1 to 2

8.26 (GPM) (LPM)

Flow Rate into cap end

10.00 (GPM) (LPM)

Directions:

1.) Enter the flow rate of the pump in gallons per minute (GPM) litres per minute (LPM)

2.) Enter the Diameter of the cylinder's Bore in in (inches) (centimeters)

3.) Enter the Diameter of the cylinder's Rod in (inches) (centimeters)

Pump Flow Rate =		(GPM) (LPM)
Diameter Bore =		inches cm
Diameter Rod =		inches cm
Area Cap End =		in^2 cm^2
Area Rod End =		in^2 cm^2

DISCLAIMER STATEMENT:

Flow rate to consider for valve selection must be consistent with:
1.) the placement of the valve in relation to the cylinder (Ex.1 or Ex.2)
2.) flow rate from port 1 to port 2

Motor Applications: Q = (S • D/231) (S • D/1000)

1.) Enter the motor shaft speed (S) in revolutions per minute (RPM)

2.) Enter the displacement of the motor in cubic inches per revolution (in^3/rev) centimeters per revolution (cm^3/rev)

S =		RPM
D =		(in^3/rev) (cm^3/rev)
Q =		(GPM) (LPM)

Setting & Pilot Ratio Calculator

Pressure Required to Lower Load

NOTE: The following equations are idealized. Back pressure at port 2 is excluded from these equations.

NOTE: Back pressure at port 2 adds to the effective setting at a rate of one plus the pilot ratio times the backpressure. Example: Using a 3:1 counterbalance valve with 200 psi of back pressure, the setting increase would be 800 psi.

Where:
L = Load induced pressure
P = Pilot pressure required to lower load
P_R = Pilot Ratio of valve (e.g. 3:1 = 3)
S = Setting of valve
C_R = Cylinder Area Ratio =

1. ) Please select a scenario

Rod Up / Retracting

Rod Down / Extending

1. ) Counterbalance valve on the blind end of the cylinder with a load

retracting

the cylinder rod.

2. ) Counterbalance valve on the rod end of the cylinder with a load

extending

the cylinder rod.

Pressure Required to Lower Load

2.) Enter the load on the actuator in lbf. kN.

F =

(lbf.) (kN.)

3.) Enter the Diameter of the Bore in inches. centimeters.

Diameter Piston/bore =		inches cm
Area Retracting =		in^2 cm^2

4.) Enter the diameter of the Rod in inches. centimeters.

Diameter Rod (dr) =		inches cm
Area Extending =		in^2 cm^2

5.) Calculated Load Induced Pressure.

Load Induced Pressure Cap =		PSI BAR
Load Induced Pressure Rod =		PSI BAR
Cylinder Area Ratio (CR) =

6.) Enter your selected valve setting in PSI. BAR.

Select a Setting (S) Value:		PSI BAR
Suggested Valve Setting:		PSI BAR

7.) Choose a Pilot Ratio that results in an acceptable
Pilot Pressure for operation of the valve.

Select a Pilot Ratio (PR):

8.) Enter estimated Back Pressure.

IMPORTANT

When you are pleased with your cracking Pilot Pressure, make a note of your chosen Pilot Ratio and Setting to be used in the load holding guide.

Estimated Back Pressure:		PSI BAR
Cracking Pilot Pressure Required Retraction * :		PSI BAR
with back pressure:		PSI BAR
Cracking Pilot Pressure Required Extension * :		PSI BAR
with back pressure:		PSI BAR

Cracking Pilot pressures shown are theoretical estimates only.

Terms of Use for the Sun Hydraulics QuickSelect™ Load Holding Valve Guide

IMPORTANT - Please read the following Terms of Use before using the QuickSelect™ Load Holding Valve Guide. By using the QuickSelect™ Load Holding Valve Guide, you agree to comply with and be bound by the conditions stated within the Terms of Use. If you do not agree with the conditions stated below, please refrain from using the QuickSelect™ Load Holding Valve Guide.

read "Terms of Use"

1. PURPOSE

Sun Hydraulics provides the QuickSelect™ Load Holding Valve Guide solely as a means of supporting technical calculations and does not provide the QuickSelect™ Load Holding Valve Guide for the purpose of consulting or warranties concerning the selection of products. The user takes full responsibility for the use of the QuickSelect™ Load Holding Valve Guide.

LEGAL DISCLAIMER

The creators, Sun Hydraulics (hereinafter 'AUTHOR'), of this SOFTWARE do not represent or endorse the accuracy or reliability of any of the information or content distributed or derived through the SOFTWARE. You hereby acknowledge that any reliance upon the SOFTWARE or any materials shall be at your sole risk. The content or material is on an "as is basis". The AUTHOR disclaims any and all warranties, expressed or implied. With use of this SOFTWARE, website, products or materials, in no event shall the AUTHOR be liable for any direct, indirect, incidental, punitive, or consequential damages of any kind whatsoever with respect to the material, service, and the products.

DISCLAIMER OF WARRANTY

THE SOFTWARE IS PROVIDED AS IS WITHOUT WARRANTY OF ANY KIND. TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, THE AUTHOR FURTHER DISCLAIMS ALL WARRANTIES, INCLUDING WITHOUT LIMITATION ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NONINFRINGEMENT. THE ENTIRE RISK ARISING OUT OF THE USE OR PERFORMANCE OF THE PRODUCT AND DOCUMENTATION REMAINS WITH RECIPIENT. TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY CONSEQUENTIAL, INCIDENTAL, DIRECT, INDIRECT, SPECIAL, PUNITIVE, OR OTHER DAMAGES WHATSOEVER (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS PROFITS, BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, OR OTHER PECUNIARY LOSS) ARISING OUT OF THIS AGREEMENT OR THE USE OF OR INABILITY TO USE THE PRODUCT, EVEN IF THE AUTHOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

These tutorials are presented as is, without warranty that they are applicable to a particular situation. They relate to classical theory as applied to airflow through openings.

QuickSelect LoadHolding | Sun Hydraulics

QuickSelect LoadHolding

IMPORTANT

Terms of Use for the Sun Hydraulics QuickSelect™ Load Holding Valve Guide

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