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SCREW JACKS CALCULATION
1. Calculate screw jacks effort force
1.1 Design Condition
Effort force at the end of the arm or handle F = 322.3
Weight or load Q = 11023.1
Pitch distance or lead of thread in one turn P = 0.2
Pitch radius of screw r = 0.8 lever-arm radius R = 2.4
1.2 The effort force for a screw jack when neglecting friction
can be expressed as
F = 146.1986 kg
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Doc. No :
W.O :
Revision No : B
Sheet : 1
lb 146.1986 kg.mm
lb 5000 kg
in 5 mm
in 20 mmin 60 mm
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allowable stress : 2/3 of yield strength or about 1/4 of
ultimate tensile strength
Ultimate tensile strength, 58-80ksi 400-550 MPa
Yield point, min., 36 KSI 250MPa
Source(s):
ASME II Part A
166.6667
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SCREW JACKS CALCULATION
1. Calculate screw jacks effort force
1.1 Design Condition
Effort force at the end of the arm or handle F = 464.1
Weight or load Q = 11023.1
Pitch distance or lead of thread in one turn P = 0.2
Pitch radius of screw r = 0.8 lever-arm radius R = 2.0
Motor speed N = 1400.0
Linier speed v = 15.7
Length of moving L = 39.4
Rotation of Screw N1 66.7
Gear Ration Rt 21.0
Time of rotaion t = 2.5
1.2 The effort force for a screw jack when neglecting friction
can be expressed as
F = 210.526 kg
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Doc. No :
W.O :
Revision No : B
Sheet : 1
lb 210.526 kg.mm 0.210526 kg.m
lb 5000 kg
in 6 mm
in 20 mmin 50 mm
rpm
in/m 400 mm/m
in 1000 mm
rpm
menit
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allowable stress : 2/3 of yield strength or about 1/4 of
ultimate tensile strength
Ultimate tensile strength, 58-80ksi 400-550 MPa
Yield point, min., 36 KSI 250MPa
Source(s):
ASME II Part A
166.6667
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SCREW JACKS CALCULATION
1. Calculate screw jacks effort force
1.1 Design Condition
Weight or load Q = 29.4
Lifting Screw lead Ls = 1000.0
Pitch distance or lead of thread in one turn P = 8.0
Time of rotaion t = 2.5
Raise Rate P = 400.0
Rotation of Screw N = 50.0
Rotation of Motor Nm = 1400.0
Gear Ration Rt = 28.0
1.2 Operating Input Power
Input Power = 0.7
1.3 Operating Input Torque
Input Torque = 136.1
1.4 Actuator Start-Up Torque
Start-Up Torque = 6.4
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Doc. No :
W.O :
Revision No : B
Sheet : 1
Kn 3000 kg
mm
mm
menit
mm/M
rpm
rpm
Kw
Nm
Nm
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allowable stress : 2/3 of yield strength or about 1/4 of
ultimate tensile strength
Ultimate tensile strength, 58-80ksi 400-550 MPa
Yield point, min., 36 KSI 250MPa
Source(s):
166.6667
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