7/30/2019 Motor Power Selection Light Duty Crane

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15T x 20m Span x 10.2 Lift

DG EOT Crane

Mechanical Rating Required in KW :

M x V x Cv x Cdf 

6.12 x E

Where :

Rated load = 15.0 T

Weight of hook block = 0.50 T

Weight of wire rope = 0.46 T

M = Mass of the rated load plus weight of the hook block & wirerope: 15.96 T

V = Specified Hoisting Speed: 8 m/min

Cv = Service facor for vertical motion for ac motor: 0.67

Cdf = Duty Factor Of Hoisting Mechanism for Class M8 of Crane: 1.7

Camb = Derating Factor for the required ambient Temperature (50°C): 0.88

E = Combined Efficiency Of Gears & Sheaves: ( 0.95n) x ( 0.99

m)

= 0.83

where:

0.95 = Efficiency of Gear Pair per Stage

n = No of Gear Pairs = 3

m = Total No. of Rotating Sheaves passed by each part of the

moving rope attached to the drum = 3

0.99 = Efficiency of Rotating Sheave

Mechanical Rating Required in KW

15.96 x 8 x 0.67 x 1.7 = 28.56 KW

6.12 x 0.83

Electrical power rating required in KW

= Mechanical rating

Camb

= 28.56 = 32.46 kW

0.88

Motor rating at 40°

Type: Squirrel Cage Make: Siemens Frame:

Motor Kilo Watt = 37 KW Starts/ Hr: 300

TEFC, 60% CDF, S4 Duty, IP55, 6 Pole, 1000rpm (SYN), CL-F, B3, Single Shaft Extension.

Selection of Main Hoist Motor & Brake

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15T x 20m Span x 10.2 Lift

DG EOT Crane

BrakeMin. Braking Torque Required As Per IS

= 150 % of the Rated Torque Transmitted to the Brake Drum from the suspended

Maximum Safe Load and the Brake not being taken into consideration

Min. Braking Torque required = (1.5 x 28.56 x 716) = 54.83 KGM

(750 x 0.746)

Type: DCEM Make: BCH Shoe Type Qty: 1

Torque Capacity = 74.6 KGM Drum Diameter: Ø300

7/30/2019 Motor Power Selection Light Duty Crane

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15T x 20m Span x 10.2M Lift

DG EOT Crane

Mechanical Rating Required in KW :

MVSCdf  (1100a)

6117TCamb

Where :

Rated load = 15.0 T

Weight of the Crab = 3.0 T

M = Mass of Moving Load (Weight of Crab+Weight of Rated Load) 18.0 T

V = Specified travel Speed in M/Min: 20 m/min

S = Service Factor For Providing Adequate Motor Heat Dissaption Capacity: 1.06

Cdf = Duty Factor for Horizontal Motion of Class M8 duty: 1.5

F = Overall Friction Factor for Wheels on Antifriction Brgs in KG./Tonnes: 8

a = Average Linear Acceleration Trolley in cm/s2: 10 cm/s

2

N = Resultant Mechanical Efficiency of the Drive: 0.86

T = A Factor Taken For Average Torque By The Motor: 1.7

Camb = Derating Factor for the required ambient Temperature (50°C): 0.88

Mechanical Rating Required in KW

18 x 20 x 1.06 x 1.5 x 8 + 1100 x 106117 x 1.7 981 x 0.86

= 1.16 KW

Electrical power Rating Required in KW

= Mechanical rating

Camb

= 1.16 = 1.32 kW

0.88

Motor rating at 40°C:Type: Squirrel Cage Make: Siemens Frame:

Motor Kilo Watt = 1.5 KW Starts/Hr: 150

TEFC, 60% CDF, S4 Duty, IP55, 6 Pole, 1000rpm (SYN), CL-F, B-3, Single Shaft Extension.

Selection of Cross Travel Motor & Brake

x F +981N

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15T x 20m Span x 10.2M Lift

DG EOT Crane

BrakeMin. Braking Torque Required As Per IS

= 100 % of Motor Torque

Maximum Safe Load and the Brake not being taken into consideration

Min. Braking Torque required = (1.0 x 1.16 x 716) = 1.16 KGM

(960.00 x 0.746)

Type: DCEM Make: BCH Shoe Type

Torque = 8 KGM Drum Diameter: Ø160

7/30/2019 Motor Power Selection Light Duty Crane

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15T x 20m Span x 10.2M Lift

DG EOT Crane

Mechanical Rating Required in KW (for twin drive):

MVSCdf  (1100a)

6117TCamb

Where :

Rated load = 15.0 T

Weight of crane = 7.0 T

M = Mass of Moving Load (Weight of Crab+Weight of Rated Load) 22.0 T

V = Specified travel Speed in M/Min: 50 m/min

S = Service Factor For Providing Adequate Motor Heat Dissaption Capacity: 1

Cdf = Duty Factor for Horizontal Motion of Class M8 duty: 1.5

F = Overall Friction Factor for Wheels on Antifriction Brgs in KG./Tonnes: 8

a = Average Linear Acceleration Trolley in cm/s2: 25 cm/s

2

N = Resultant Mechanical Efficiency of the Drive: 0.86

T = A Factor Taken For Average Torque By The Motor: 1.7

Camb = Derating Factor for the required ambient Temperature (50°C): 0.88

Mechanical Rating Required in KW

22 x 50 x 1 x 1.5 x 8 + 1100 x 25 x 0.666117 x 1.7 981 x 0.86

= 4.25 KW

Electrical power Rating Required in KW

= Mechanical rating

Camb

= 4.25 = 4.83 kW

0.88

Motor rating at 40°C:Type: Squirrel Cage Make: Siemens Frame:

Motor Kilo Watt = 5.5 KW Starts/Hr: 150 Qty: 2Nos.

TEFC, 60% CDF, S4 Duty, IP55, 6 Pole, 1000rpm (SYN), CL-F, B-3, Single Shaft Extension.

x F +981N

Selection of Long Travel Motors & Brakes

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15T x 20m Span x 10.2M Lift

DG EOT Crane

BrakesMin. Braking Torque Required As Per IS

= 100 % of Motor Torque

Maximum Safe Load and the Brake not being taken into consideration

Min. Braking Torque required = (1.0 x 4.25 x 716) = 4.25 KGM

( 960.00 x 0.746)

Type: DCEM Make: BCH Shoe Type Qty: 2Nos.

Torque = 8 KGM Drum Diameter: Ø160