Net Hauler
Net Hauler
This machine is used for the work of lifting net. Its capability is from 1 to 3 tons and can save the net lifting labor work.
Outer dimension
Specification
Ex) Model : GH218
I Main calculation formula of hydraulic pressure device

Hydraulic pump
 1) axis input of a pump
Ls=(P･Q/60η)･102  2) Oil power of the pump
Lp= P･Q/60＝η･Ls・102  3) Total efficiency of the pump
η=ηv･ηt・102  4) Capacity efficiency of the pump
ηv=(Q/Qth)･100≒(Q/Q0)･100  5) Efficiency of the motor
ηe= Ls/ Le
 1) axis input of a pump

Hydraulic motor
 1) Theoretical Displacement volume of Hydraulic motor
Dth=(2π･T)/(P･ηt)･102  2) Output power of Hydraulic motor
Ls=2π･T･N/60000=η･(P･Q/60)･102  3) Input power of Hydraulic motor
Lm=P･Q/60  4) Capacity efficiency of Hydraulic motor
ηv= (Dth･N/Q)･101  5) Torque efficiency of Hydraulic motor
ηt= (2π･T/P･Dth )･102  6) Total efficiency of Hydraulic motor
η=ηv･ηt･102= (Ls/ Lm)･102=(2π･T･N/P･Q)･101
 1) Theoretical Displacement volume of Hydraulic motor

Cylinder
 1) Necessary pressure to a cylinder
P1=(1/ A1)･(F/ηc+P2･A2･102) ･102  2) Necessary flow rate for a cylinder
Q= A1･v･101+QL  3) Driving force of a cylinder
Acceleration ability
F1=m･α=m･v1/t
Static wear resistance
F2= μs･m･g
Dynamic wear resistance
F3= μd･m･g
 1) Necessary pressure to a cylinder
The explanations of symbols
Ls: input of pump shaft, output power of the motor, the output power of the motor (kW)
Lp: oil power of the pump (kW)
Le: input power of the motor (kW)
Lm: input power of the motor (kW)
P: Discharge pressure of pump, differentialpressure of the input/output port of a motor (MPa)
P1: necessary pressure to cylinder (MPa)
P2: pressure of the cylinder inflow (MPa)
Q: discharge amount at the time of discharge pressure P,
inflow oil amount to the motor, necessary flow rate of the cylinder (large/min)
Qth: theoretical discharge amount (l/min)
Qo: discharge amount at the time of discharge pressure P≒0, (l/min)
QL: Leak inside the cylinder (l/min)
T: shaft torque (N・m)
N: number of rotations (min1)
η: Total efficiency of the pump, total efficiency of the motor (the %)
η v: capacity efficiency of pump, capacity efficiency of the motor (the %)
η t: torque efficiency of pump, torque efficiency of the motor (the %)
η e: efficiency of motor (the %)
η c: driving force efficiency of cylinder (0.90.95)
Dth: theoretical displacement volume of the motor (cm3/rev)
A1: inlet side pressure receiving area of cylinder (cm2)
A2: outlet side pressure receiving area of cylinder(cm2)
F: cylinder driving force (N)
F1: cylinder acceleration force (N)
F2: static wear resistance (N)
F3: dynamic wear resistance (N)
v: The speed of the cylinder (m/min)
v1: The speed after acceleration (m/s)
m: The mass of the load (KG)
α: acceleration (m/s2)
t: acceleration time (s)
μ s: static friction coefficient
μ d: dynamic friction coefficient
g: acceleration of the gravity (m/s2)