Present Status and Periodical Inspection of Large Capacity Cylinders for Tube Trailers in China

Tube trailers with large capacity seamless steel cylinders have been used more and more widely in China to transport industrial gases. As an authorized tube trailer inspection organization by the government of China, China Special Equipment Inspection and Research Institute has carried out periodical inspection of tube trailers in China since 2004. A statistical analysis was done based on 4059 periodical inspection reports of tube trailers from 2004 to 2013, which include 3687 tube trailers and 31627 cylinders. Information of present status of tube trailers in China was obtained, such as annual amounts, usage regions of tube trailers, numbers of cylinders mounted on tube trailers, and specifications, filling mediums, typical flaws of the cylinders. The statistical results show that mounting threads of 16.16% of the cylinders were worn seriously, and repair or reprocess work had to be done on these threads. Reasons of the abrasion of the mounting threads were analyzed and discussed by taking into account the usage regions of the tube trailers, the detailed structures of the mounting threads, and the mounting location of cylinders on the tube trailers.Copyright © 2014 by ASME