Parker 1P1V-S020A00005, Руководство пользователя

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57
Stainless Steel Air Motors P1V-S
07.10
www.parker.com/euro_pneumatic
Theoretical calculations
This section provides you with the background you need in
order to select the right air motor for common applications.
The first four parts explain the direct physical relationships
between:
Force - Torque - Speed - Power Requirement
Before selecting an air motor, you need to know the torque
required by the application at the necessary speed. Some-
times, the torque and the speed are not known but the power
requirement and the speed of movement are. You can use the
following formulas to calculate the speed and torque.
Power
The power requirement is always calculated in N.
Formula:
F = m x g
F = power in N
m = mass in kg
g = gravitation (9,81) in m/s
In this example, the mass is 150 kg
F = 150 x 9,81 N
F = 1470 N
Torque
Torque is the force applied to produce rotational motion (rota-
tional force) or the force applied in the opposite direction. It is
the product of the rotational force F and the distance from the
pivot point (radius or moment arm)
Formula:
M = m x g x r
M = torque in Nm
m = mass in kg
g = gravitation (9,81) in m/s
r = radius or moment arm in m
In this example, the drum diameter is 300 mm, which
means the radius r = 0,15 m, and the mass is 150kg.
M = 150 x 9,81 x 0,15 Nm
M = 1 Nm
Speed
The required motor speed can be calculated if the speed of
movement and the radius (diameter) are known.
n = v x 60/( x
π
x r)
n = motor speed in rpm
v = speed of movement in m/sec
r = radius in m
π = constant (3,14)
In this example, the speed of movement is 1,5 m/s
and the drum diameter is 300 m (radius r = 0,15 m)
n = 1,5 x 60/( x
π
x 0,15) rpm
n = 96 rpm
Power Requirement
The power requirement can be calculated if the motor speed
and torque are known.
P = M x n/9550
P = power in kW
M = torque in Nm
n = rpm
9550 = conversion factor
In this example, a torque of 1,5 Nm is required
at a speed of 1500 rpm.
P = 1,5 x 1500/9550
P = 0,196 kW or approx. 00 Watt
150 kg
r
M
r
v
n
150 kg
F
M, n