CONCRETE POLES

Waipa Post, Volume 36, Issue 2147, 21 April 1928, Page 5

CONCRETE POLES

FOR POWER TRANSMISSION LINES. TE AWAMUTU BOARD INTERESTED. The relative advantages of concrete and hardwood poles were discussed once again at yesterday's meeting of Te Awamutu Electric Power Board. The secretary reported that four firms tendered for supplying 329 ironbark poles, and that of F. H. Claxton, Thames, at £1055 8s 9d, was accepted. The poles must be hewn free of sapwood and delivered free on trucks at Auckland. Mr Macky inquired if the hewn poles were more economical than the untrinimedohes. The secretary said the cost was practically the .same. The initial cost was higher, but freight was saved.

" Aren't you going to try using concrete poles?" inquired Mr Montefiore, who added that he and Mr Teasdale had recently inspected this class of pole in the Waitomo Board's area. He believed they were giving good service, and he wa.s more impressed than ever with the suitability of concrete poles for this district. Too many of the present poles were rotting. Mr Sutherland said in Germany in the past five years concrete poles were largely used. He gave particulars of their use, adding that poles up to 40 feet in length were used. Mr Montefiore said the quality of wooden poles from Australia was not high enough. Concrete poles were better value, and their construction would provide employment for many people. There was plenty of suitable shingle available. If tests proved the concrete poles were not strong enough, then concrete bases should be used, and hardwood poles bolted in. " I believe you are right," commented Mr Sutherland.

The chairman said he was not opposed to the use of concrete poles, but he would like to wait a while to see jyhgther Waitomo and other boards using concrete were satisfied with their experiments. He reminded members that engineers had recommended the use of hardwood in preference to concrete poles. Further, the Government departments were still using hardwood poles.

Mr Montefiore said the cost was practically the same. The shingle obtainable near Parawera would make as good concrete poles as any in New Zealand.

The chairman said mistakes had been made in the past in buying herd wood, but he wanted to avoid a repetition. He preferred to give the concrete poles time to prove their efficiency and economy. Mr Spinley said it was usually the case that bases of hardwood poles did not rot. The chief place where rot occurred was about half way up. He was favourably disposed to the use of concrete poles. The manager said his inquiries from engineers led to the belief that poles bolted to concrete bases would not stand the strain. If a wire broke the pole would split. Mr Spinley referred to the likelihood of reticulating the Harapepe district. Why not use concrete poles there, and watch results? There was plenty of good ,shihgle handy to make the poles in that district. This would save a lot of carting. Mr Teasdale expressed himself as convinced that concrete ; poles were the more economical. Mr Montefiore said the fact that the making of concrete poles would afford employment in New Zealand should be a consideration. At present the Board was affording employment for Australian workers.

The chairman said there were poles in use still that had been put up when the Board first started operations. Mr Spinley said that some of the poles purchased in the first two years were a bad investment; but betterquality poles were now procured. Mr Montefiore said the quality was still below requirements. Mr Spinley said the poles supplied nowadays all had to pass inspection by an officer of the New South Wales Forestry .Department. Only, rrpnbark was brought from Australia- Silver pine grVrwn in New Zealand .was used for service lines. ;• Mr Montefiore said members could argue all day without making much progress; but he was convinced that the Board should establish a plant and make concrete poles. Mr Spinley suggested calling tenders for supply of concrete poles. The chairman said data was obtainable from the Waitomo Board, whose officials and members were very willing to give any desired information. As a matter of fact, the Waitomo Board, when it had made all the poles it required, offered to sell Te Awamutu the plant. It was decided to seek further information on the subject for the next meeting.