16.31: Use of API specified steel tubes for infrastructure applications in Europe

Abstract

ABSTRACTThe lack of ready availability of large diameter steel tubes/pipes (greater than 508mm) which are CE marked for use in Europe can often cause delays in construction. There can also be minor or major alterations in design when alternative tube sections which are already available are proposed. In the UK highways network, large diameter tubes are extensively used for sign and signal support cantilever gantries and the demand for them can be very high for the highways market, often with very short delivery programme requirements. Following the cessation of the rolling of large diameter tubes from UK mills, the alternative options for cantilever gantries are either to amend the design using a truss leg formed from smaller hollow sections, to source a CE marked tube from outside the UK, or to use tubes specified to the American Petroleum Institute (API) which have ready availability from the oil and gas market.This last option is discussed and a comparison review is undertaken for tube sections specified between API Specification 5L [1, 2] and BS EN 10210/BS EN 10219 [3, 4] for hot rolled/cold formed sections. This study has already been used and accepted by the Technical Approval Authorities of the UK's primary road network, Highways England, for highway gantries, and therefore can validate the use of API specified tubes (which are a common by product material from the Oil and Gas industry, the tubes in question being effectively off cuts from pipeline construction), for broader infrastructure applications. This is a significant contribution in the construction sector especially in high demand periods for steel tubes, with added value from the reduction of carbon footprint caused by using already fabricated surplus material.