Final answer:
To determine the developed length for a 30° bend in a conduit around a silo, we calculate the silo's circumference with the conduit 8 inches away, then find the proportional length of a 30° section of that circumference. The calculated developed length is approximately 13.35 feet.
Step-by-step explanation:
To calculate the developed length of a 30° bend around the outside diameter of a silo using a 5-inch RMC (Rigid Metal Conduit), we'll follow these steps:
- First, we determine the silo's circumference given the measurement from the straight edge to the silo wall. Since the distance is 14.75 feet at both ends, the radius (r) is the length of the straight edge plus the measured distance, totaling 24.75 feet. The diameter (d) is therefore 2 * r = 49.5 feet.
- To find the circumference (C), we use the formula C = π * d which yields approximately 155.48 feet.
- Since the conduit needs to be 8 inches away from the silo, the effective diameter to consider for the bend is increased by 16 inches (8 inches on both sides). Converting 16 inches to feet we get ´1.3333 feet, which is to be added to the silo's diameter, resulting in 50.8333 feet.
- Now we calculate the effective circumference with this increase, C' = π * (49.5 + 1.3333) feet yielding approximately 160.22 feet.
- With the effective circumference known, we then find the length of the 30° bend (L_bend) by using the proportion L_bend/C' = 30/360, as 30° is 1/12 of a full circle of 360°. So, L_bend = (30/360) * 160.22 feet, which gives approximately 13.35 feet.
The developed length of the 30° bend to be created in the RMC to go around the silo, maintaining an 8-inch gap from the silo, is approximately 13.35 feet.