Two-Stage Electrohydraulic Flow Controlling Servo Valve with Two Nozzles and Flapper Force Feedback
Design Features:
（1）Using dry torque motor and two stages of hydraulic amplification structures: the pre stage is a friction free flapper valve of two nozzles.
（2）High valve-core driving force, steady zero, high sensibility, high resolution, low hysteresis, and long reliability in service.

Specification:
QDY6
Supply oil pressure range (MPa) 1.5-31.5
Rated supply oil pressure (MPa)31.5
Rated flow Qn (L/min) (at valve pressure drop of 7MPa) 4,10,20,40,60
Rated current ln (mA) 15,30,40,80
Hysteresis(%) ≤3
Resolution(%)≤0.5
Non linearity(%) ≤±8
Asymmetry(%) ≤±10
Internal leakage (L/min)≤1.3
Bias(%)≤±3
Zero drift of supply oil pressure ≤±2
Zero drift of return oil pressure ≤±4
Frequency characteristics
Amplitude frequency width(-3dB)(Hz) 60-100
Phase frequency width(-90°)(Hz)60-100
Net weight(kg) 1.2


Model: QDY10
Supply oil pressure range (MPa)1.5~28
Rated supply oil pressure (MPa)25
Rated flow Qn (L/min) (at valve pressure drop of 7MPa)100,125,150
Rated current In (mA)40,80
Hysteresis (%)≤3
Resolution (%)≤0.5
Non linearity (%)≤±10
Asymmetry (%)≤±10
Pressure gain (%Ps/1%In)＞30
Internal leakage (L/min)≤2.5
Bias (%)≤±3
Zero drift of supply oil pressure (80-110% Ps) (%)≤±3
Zero drift of return oil pressure (0-20% Ps) (%)≤±2
Zero drift in temperature (-30~+150℃) (%)≤±4
Frequency characteristics
Amplitude frequency width (-3dB) (Hz)＞35-50
Phase frequency width (-90°) (Hz)＞30-50
Net weight (kg) 4.0 for al. body, 7.5 for steel body

Model: QDY11B
Supply oil pressure range (MPa)1.5-21
Rated supply oil pressure (MPa)16
Rated flow Qn (L/min) (at valve pressure drop of 7MPa)200,250
Rated current In (mA)15,30,40
Hysteresis (%)≤4
Resolution (%)≤1
Non linearity (%)≤±10
Asymmetry (%)≤±10
Pressure gain (%Ps/1%In)>25
Internal leakage (L/min)≤3.2
Bias (%)≤±3
Zero drift of supply oil pressure (80-110% Ps) (%)≤±3
Zero drift of return oil pressure (0-20% Ps) (%)≤±2
Zero drift in temperature (-30~+150 ℃) (%)≤±4
Frequency characteristics
Amplitude frequency width (-3dB) (Hz)>20
Phase frequency width (-90°) (Hz)＞25
Net weight (kg) 6.5


Model: QDY12
Supply oil pressure range (MPa)1.5-25
Rated supply oil pressure (MPa)21
Rated flow Qn (L/min) (at valve pressure drop of 7MPa)4,10,20,40
Rated current In (mA)30,40
Hysteresis (%)≤3
Resolution (%)≤0.5
Non linearity (%)≤±8
Asymmetry (%)≤±10
Pressure gain (%Ps/1%In)>30
Internal leakage (L/min)≤1.2
Bias (%)≤±3
Zero drift of supply oil pressure (80-110% Ps) (%)≤±2
Zero drift of return oil pressure (0-20% Ps) (%)≤±2
Zero drift in temperature (-30~+150 ℃) (%)≤±4
Frequency characteristics
Amplitude frequency width (-3dB) (Hz)>120
Phase frequency width (-90°) (Hz)>120
Net weight (kg)1.4

Model: QDY14
Supply oil pressure range (MPa)1.5-25
Rated supply oil pressure (MPa)21
Rated flow Qn (L/min) (at valve pressure drop of 7MPa)4,10,20,40
Rated current In (mA)30,40
Hysteresis (%)≤3
Resolution (%)≤0.5
Non linearity (%)≤±8
Asymmetry (%)≤±10
Pressure gain (%Ps/1%In)>30
Internal leakage (L/min)≤1.3
Bias (%)≤±3
Zero drift of supply oil pressure (80-110% Ps) (%)≤±2
Zero drift of return oil pressure (0-20% Ps) (%)≤±2
Zero drift in temperature (-30~+150 ℃) (%)≤±4
Frequency characteristics
Amplitude frequency width (-3dB) (Hz)60-100
Phase frequency width (-90°) (Hz)60-100
Net weight (kg)0.9

Model: QDY15
Supply oil pressure range (MPa)1.5-25
Rated supply oil pressure (MPa)21
Rated flow Qn (L/min) (at valve pressure drop of 7MPa)4,10,20,40
Rated current In (mA)30,40
Hysteresis (%)≤3
Resolution (%)≤0.5
Non linearity (%)≤±10
Asymmetry (%)≤±10
Pressure gain (%Ps/1%In)>30
Internal leakage (L/min)≤1.5
Bias (%)≤±3
Zero drift of supply oil pressure (80-110% Ps) (%)≤±2
Zero drift of return oil pressure (0-20% Ps) (%)≤±2
Zero drift in temperature (-30~+150 ℃) (%)≤±4
Frequency characteristics
Amplitude frequency width (-3dB) (Hz)>50
Phase frequency width (-90°) (Hz)>60
Net weight (kg)0.8