As a general rule any bushings or pieces brazed in or on a copper boiler should be bronze (copper/tin alloy or gun metal which is copper/tin/zinc/lead. The tin seems to eliminate the problem of the zinc leaving the alloy, you could use copper too for fittings directly on the boiler but copper is a bear to machine cleanly (I know from when I tried to thread copper rivets for stay bolts). What I did was to use bronze bushings every place a line goes into our out of the boiler, but ordinary brass for valve bodies, gauge glass etc as that stuff can be replaced without harming the main boiler shell. The zinc leaving an alloy is really apparent with some of the die casting alloys high in zinc. When I was doing lab work in house hold appliances we had die cast garbage disposers simply drop out of a sink where the zinc alloys just turned to powder. Same with some die cast electric meter bodies used near the sea, just crumbled to pieces. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://postfix.45mm.com/pipermail/sslivesteam/attachments/20061125/e9c1c902/attachment.html _______________________________________________ SSLiveSteam mailing list Send messages: [email protected] Cancel subscription: http://postfix.45mm.com/mailman/listinfo/sslivesteam Rules: http://www.45mm.com/sslivesteam_guide.html
