Circular hollow cross-sections are better for longer poles.Because hollow,weigh less.And because they are  spun at high speeds in casting operation,then concrete is denser and stronger

 

 

 

Technical Index of Centrifugal type Concrete Pole Machine

No.	Item		Unit	Model
				Double-wheel	Three-wheel
1	Riding wheel thread		MM	1870
2	Riding wheel wheelbase		MM	1500-2800
3	Riding wheel external diameter		MM	800-920
4	Riding wheel width		MM	100
5	Angle between wheel center and the center of steel mould		(°)	75°-110
6	The Max. length of molding drainage pipe		M	2-4
7	The Max. diameter of molding drainage pipe	Plain top/tongue and groove/pipe-jacking	MM	Φ2600	Φ1800
		Bell and spigot		Φ1800	Φ1800
8	The motor power		KM	37-90	55-132
9	The range of speed of main drive axle		r/min	100-500(continuous)	100-500(continuous