<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31439496</termId><termName>Pittsburgh lock seams</termName><termType>PT</termType><termNote><![CDATA[ Distinctive sheet metal seams made with one sheet edge turned, double-bent, and locked onto a sheet having a simple bend; usually created using a special Pittsburgh lockforming machine. An example of use for the seam is at the corners of elbows and square or rectangular pipes of ducts. ]]></termNote><termCreatedDate>2026-03-30 20:58:28</termCreatedDate><relation><relationType>UF</relationType><termId>31439497</termId><termName>Pittsburgh lock seam</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31439498</termId><termName>Pittsburgh seam</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31439499</termId><termName>seams, Pittsburgh lock</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31414163</termId><termName>metal seams</termName><termType>PT</termType></relation></term>  </Zthes>