Requirements on the strength of rubber hose assemblies for high pressure acetylene

Abstract

According to the German Technical Rules for Acetylene Installations and Calciumcarbide Stores (TRAC), TRAC 204 “Acetylene Pipelines” No. 5.3.7., hose assemblies for high pressure acetylene must be tested for sufficient strength to withstand the decomposition of acetylene at the maximum permitted pressure. Until now, all rubber hose assemblies produced for use in high pressure hydraulic systems have failed this approval test. The same rubber hose assemblies fitted with a spiral inside the hose on its full length have successfully passed this approval test. These rubber hose assemblies could be recommended for type approval by the Federal Institute of Materials Research and Testing (BAM) and have been type approved for use in installations for high pressure acetylene according to Article 10 of the German Acetylene Regulations by the competent approval authority in Germany. In this report we have summarized the experience of BAM resulting from experiments with decomposition of high pressure acetylene in tubes and rubber hose assemblies. On the basis of the results of these investigations appropriate requirements for rubber hose assemblies can be made so that in case of a hazard with a decomposition of high pressure acetylene there will be no failure of any rubber hose assembly within the installation.