Fa: Axial Load (kN)Fr: Radial Load (kN)Me: Tilting Moment (kNm)  Q: Load to be lifted (kN)A: Lifting Arm Weight (kN)B: Balance Arm Weight (kN)G: Stabilizing Load (kN)W:Wind Load (kN)lmax: Lifting Weight Length (max) (m)a: Lifting Arm Center of Gravity Length (m)b: Balance Arm Center of Gravity Length (m)g: Balance Arm Length (m) r: Wind Effect Distance with DTD (m) Fa= Q + A + B + GMe= (Q.lmax) + (A.a) – (G.g) – (B.b)   25 % Test Load Added:Fa= (1,25.Q) + A + B + GMe= (1,25.Q.lmax) + (A.a) – (G.g) – (B.b)   Wind Effect Added: Fa= Q + A + B + GMe= (Q.lmax) + (A.a) + (W.r) – (G.g) – (B.b)
 You can easily calculate the axial loads and tilting moments on the Slewing Rings using the above equations. It is suggested that you use the maximum load and maximum distance values in your calculations. You can include additional test load and wind effect if you wish.

SAMPLE CALCULATION

 Q: 60 kN lmax: 30 m A: 30 kN a: 15 m B: 15 kN b: 5m G: 150 kN g: 10 m W: 20 kN r: 2 m

Fa= Q + A + B + G
Fa= 60 + 30 + 15 + 150
Fa= 255 kN

Me= (Q.lmax) + (A.a) – (G.g) – (B.b)
Me= (60.30) + (30.15) – (150.10) – (15.5)
Me= 675 kNm

 lmax: 30 m A: 30 kN a: 15 m B: 15 kN b: 5m G: 150 kN g: 10 m W: 20 kN r: 2 m

Fa= Q + A + B + G
Fa= 60 + 30 + 15 + 150
Fa= 255 kN

Me= (Q.lmax) + (A.a) – (G.g) – (B.b)
Me= (60.30) + (30.15) – (150.10) – (15.5)
Me= 675 kNm

 SAFETY FACTOR (f): : 1,25Fa’= f.FaFa’=1,25.255Fa’=318,75 kN Me’= f.MeMe’= 1,25.675Me’=843,75 kNm

When we place our results on the graph, we see that the Slewing Rings number “4” is suitable

SAFETY FACTOR (f):

Loads should be multiplied with the safety factor suitable to the application area prior to gear selection after calculations are completed.

 APPLICATION AREA SAFETY FACTOR (f) Tower Cranes 1.25 Mobile Cranes 1.50 Harbor Cranes 1.25 Excavators 1.70 Concrete Pumps 1.50 Vehicle Mounted Platforms 1.35 Solar Energy Systems 1.25 Wind Energy Systems 2.00 Roller Systems 2.00 Industrial Designs 1.25 Radar Systems 1.10 Water Filtration Systems 1.25

f: Safety Factor

Me:Tilting Moment