Double-walled pipe formation method involves joining inner and outer pipes to form pipe assembly, filling pipe assembly with filling medium, freezing filling medium, and heating pipe assembly for discharge of filling medium
摘要
<p>The method involves joining an inner pipe into an outer pipe with a space formed between the pipes to form a pipe assembly (1). The space is filled with a filling medium (10) which is cooled to freeze the filling medium in the pipe assembly. The pipe assembly is heated to modify state of aggregation of the filling medium for discharge of the filling medium from the pipe assembly. An independent claim is also included for the use of the double-walled pipe formation method.</p>
