| 摘要 |
PROBLEM TO BE SOLVED: To secure a specific margin securely without error to each size respectively, as well as to be released from the conventional complicated marking work, when two pipes are inserted and joined each other. SOLUTION: While a pipe end standard line to be a positioning standard is printed to a marking seal 1, when a seal main body 2 is stuck to the pipe end of an insertion pipe, perforation 41 to 47 in the seal width direction are formed respectively by placing the distances of the inserting margin parts corresponding to the pipe sizes, by making the pipe end standard line as the standard, to each size of the pipes, and the pipe sizes responding to those perforations 41 to 47 are displayed. |
