1) Brier section 2) Corncob section 3) It comes out of a bowl 4) Meerschaum part 5) Puff piece 6) Smoky spot 7) Very thin arm or leg Found on https://www.crosswordclues.com/clue/pipestem
Pipe'stem` noun The hollow stem or tube of a pipe used for smoking tobacco, etc. « Took a long reed for a pipestem .» Longfellow. Found on http://www.encyclo.co.uk/webster/P/93