[Steam-engine] Fusible plug

[Bruce & Marlene Babcock]

Andy,

    ASME fusible plugs have standard NPT pipe threads.

    I suggest that you simply take a 3/4-inch and a 1-inch pipe coupling and
see which one the plug fits.  If you have a vertical boiler with a
water-side plug or if your boiler is small, you may have a 1/2-inch plug.

    Not all old fusible plugs had standard NPT pipe threads.  I have seen at
least one old, square-headed plug with unusual threads.

    If your plug is a marine plug it may have standard NPT threads except
that the length of the threads may be greater and the larger diameter
bigger.  This was done because the Federal Government specified, and
enforced, the frequent replacement of marine fusible plugs.   These special
plugs would fit holes that had become stretched out from frequent
replacement of the plugs.   If the hole in your crown sheet is not stretched
out you will not need to replace you plug with a special marine plug.  You
probably could not find one.  They have not been manufactured for many
years.

Sincerely,

Bruce E. Babcock



----- Original Message ----- 
From: "Andy glines" <pioneersop96 at yahoo.com>
To: "Steam" <steam-engine at lists.stationary-engine.com>
Sent: Monday, September 20, 2004 1:29 PM
Subject: [Steam-engine] Fusible plug


> I finally got the plug out of my engine and need to
> know how I determine its size.  Where do I measure to
> find out what size of plug my boiler uses?  Are there
> special fusible plug threads?  These don't really look
> like pipe threads to me.
>
> =====
> Andy Glines
> Evansville, IN
>
>
>
> __________________________________
> Do you Yahoo!?
> Yahoo! Mail is new and improved - Check it out!
> http://promotions.yahoo.com/new_mail
> _______________________________________________
> Steam-engine mailing list
> http://www.stationary-engine.com/mailman/listinfo/steam-engine
>