Drainage and Sewerage # 1974 Southampton
At the second International Plastics Pipes Symposium held at this University in September, 1972, Dr. J. Dotzauer of Kunststoffwerk Gebrueder Anger GmbH delivered a paper entitled “Six Years of Experience with uPVC pipes and sewers in West Germany”. Much interest was aroused at the Symposium by this paper, not least by the figures given to indicate the quantities and value of uPVC sewers and drainage being sold in West Germany at that time.
Dr. Dotzauer explained how at Kunststoffwerk Gebrueder Anger GmbH work had started as early as 1961 upon investigations into the behaviour of uPVC pipes when buried and he indicated the extent of work which had been carried out — with particular reference to the effects of different backfili materials and conditions at the University of Munich, All of this work culminated in 1966 with the award to Kunststoffwerk Gebrueder Anger GmbH of the P.A. mark by the Institute for Building Technique in Berlin.
For those not familiar with the approvals system in Germany the P.A. mark may be considered to be similar in many ways to the British Standards Institution’s Kitemark in the United Kingdom.
Initially, the award of the mark referred to applied to pipes and fittings having outside diameters of 110, 125, 160 and 200mm only, and with diameter/wall thickness ratios varying from 37 to 44.
In 1969, an eXtension to the mark was granted which included diameters of 250, 315, 400 and 500mm having diameter/wall thickness ratios of 41.
Much of the reasoning underlying the choice of the ratios referred to was dealt with in Dr. Dotzauer’s paper and need not be repeated here. It may be of interest to note, however, that practical experience with the larger diameter sewer pipes and fittings is now extensive, dating back at least as far as 1967 in the case of 250mm when 2,200 linear metres were laid as part of a large sewerage scheme at Penzberg. 300mm systems were being laid very shortly after, and many contracts, including those at Dornwang, Gemeinde Pietling and an extension at Penzberg were carried out in 1970 using 400mm pipes and fittings. uPVC sewer pipes in thse sizes and larger are now in extensive use all over West Germany.