PilotOperatedCheckValve

    PilotOperatedCheckValve

Library

HydraulicsByFluidon/Components/Valves/CheckValves

Description

The component PilotOperatedCheckValve allows free flow through the check valve from A to B and blocks the reverse flow until the pilot pressure directly proportional to the load in the pilot line, so that the pilot piston can push the check poppet off its seat. The component PilotOperatedCheckValve is the model of a check valve which blocks the flow in the direction from fluidPortB towards fluidPortA. In the opposite direction, from fluidPortA towards fluidPortB, the valve can be set to represent either a throttle or orifice. In addition to pressure at fluidPortA the valve can be opened by pressure at fluidPortPilot.

The locking function is thereby represented by a spring. The Opening pressure difference is the pressure difference necessary to overcome the locking spring force. The opening condition is:

fluidPortA.p + Pilot ratio * Pilot pressure > fluidPortB.p + Opening pressure difference.

with Pilot ratio = Pilot piston area / Check valve seat area

Max. opening pressure difference defines the point where the valve is completely open and the values Nominal volume flow and Nominal pressure difference apply. From Opening pressure difference to Max. opening pressure difference the flow is scaled proportionally.

Throttle

Orifice

The component PilotOperatedCheckValve is not a model of a check valve according to its physical structure. It merely represents the characteristic behavior of a check valve. The dynamic effects which can occur in real valve such as forces due to inertia will be represented by means of the parameter TimeConstant, which is the time constant of an idealized first order mechanical system that can not oscillate.

Parameters

PilotOperatedCheckValve_0

NameLabelDescriptionData TypeValid Values

mo_pilotRatio

pilotRatio

Pilot ratio

Scalar

mo_OpeningPressure

OpeningPressure

Opening pressure difference

Scalar

mo_MaxOpeningPressure

MaxOpeningPressure

Max. opening pressure difference

Scalar

mo_NominalVolumeFlow

NominalVolumeFlow

Nominal volume flow

Scalar

mo_NominalPressureDifference

NominalPressureDifference

Nominal pressure difference

Scalar

mo_resistorType

resistorType

Type of the resistor

Structure

mo_resistorType/choice1

Orifice

Number

0
1

mo_resistorType/choice2

Throttle

Number

0
1

mo_ReferenceDensity

ReferenceDensity

Reference density for volume flow and pressure difference

Scalar

mo_TimeConstant

TimeConstant

Time constant of the first order delay

Scalar

mo_deadVolume

deadVolume

Dead volume at ports

Scalar

PilotOperatedCheckValve_1

NameLabelDescriptionData TypeValid Values

mo_forwardFluidProperties

forwardFluidProperties

Forward fluid properties between ports

Scalar

true
false

PilotOperatedCheckValve_2

NameLabelDescriptionData TypeValid Values

mo_volumeFlowA

volumeFlowA

volumeFlowA

Structure

mo_volumeFlowA/fixed

fixed

Cell of scalars

true
false

mo_volumeFlowA/start

start

Cell of scalars

mo_volumeFlowB

volumeFlowB

volumeFlowB

Structure

mo_volumeFlowB/fixed

fixed

Cell of scalars

true
false

mo_volumeFlowB/start

start

Cell of scalars

mo_pA

pA

pA

Structure

mo_pA/fixed

fixed

Cell of scalars

true
false

mo_pA/start

start

Cell of scalars

mo_pB

pB

pB

Structure

mo_pB/fixed

fixed

Cell of scalars

true
false

mo_pB/start

start

Cell of scalars

Ports

NameTypeDescriptionIO TypeNumber

fluidPortA

implicit

Hydraulic port A

input

1

fluidPortB

implicit

Hydraulic port B

input

2

fluidPortPilot

implicit

Hydraulic port pilot

input

3