Increase in weight after bunching

Dear Sir,
How can i Calculate increase in weight of the conductor after bunching of the conductors. Suppose 140 wires bunched in double twist machine with wire dia 0.285. Calculated weight will be 79.4 Kg/Km. But What will be the increase in weight after bunching.

Regards

In double twisting, you can have a number of strands randomly moving about in the finished conductor. Is this what you are doing? It is called double twist bunching.

Likewise in double twisting, you can have a series of strand layers, each closed separately to control the position of the strands in each layer. Perhaps this is what you are doing. It is called double twist stranding.

In either case, there is excess length in the strands to account for the twist (s) in the conductor. By determining the angle of the conductor twist, use the Pythagorean theorem to account for the excess length in the bunched strands as above and sum to obtain the conductor weight. ( en.wikipedia.org/wiki/Pythagorean_theorem )

In case of double twist stranding, use the angle of strand twist for each layer of strands and sum the weight of the strands in each layer to obtain the conductor weight.

Another location to understand increase in weight by stranding is the Stewart-Hay web page www.stewart-hay.com/PSH%20Wire.htm . Look under the sub-heading "The Penalties of Pitch"

Please note. In future please keep the threads on subject. "Double Twisting of Strands" belongs in the "Nonferrous Division" but "Pressure Extrusion" belongs in the "Electrical Division". Thank you.