It 16mn- symmelske fjouwerkantpipe is in fjouwerkantstânpipe mei fjouwer hoeken en in fjouwerkantstânpipe kâld tekene en út in symmelske stânpipe.Der is in grutte ferskil tusken in seamless fjouwerkantpipe en in welded fjouwerkantpipe.Steel pipes have a hollow section and are used in large quantities as pipes for conveying fluids.