What is the correct way to measure throat on saddle weld?

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Hello:I am still learning and wanted to get some comment on saddle weld measurement.Here is a picture of the saddle completed:http://s943.photobucket.com/albums/a...ent=saddle.jpgHere is a picture of the saddle weld measured from line of pipe:http://s943.photobucket.com/albums/a...easurement.jpgHere is a picture attempting to measure the saddle weld from the curvature of the pipe:http://s943.photobucket.com/albums/a...addle_part.jpgI feel kinda funny measuring the weld from the curvature of the pipe.  Is there a better way or measurement tool then the one I am using?  Any suggestions on technic?Thank you,BennyB Attached Images
Reply:To measure the throat you need to measure the leg sizes and then do a little figuring. Draw a picture. Think of the fillet weld as a right triangle. The leg size measurements will be the opposite (a^2) and adjacent (b^2) sides. The hypotenuse (c^2) is the measurement that you need to figure out. This can be done by plugging your measurements into the Pythagorean theorem. (a^2+b^2=c^2). Now draw a line from the the right angle to the midpoint on the hypotenuse (this line represents the throat of the weld) and divide the length of the hypotenuse by 2. now use trig to solve for the missing length. Note if you are working with a weld of equal leg sizes measurements the throat of the weld is equal 1/2 the measurement of the hypotenuse. EDIT: this is a figured number, the actual throat size could differ because of bead profile. I.E underfill, excessive reinforcement.hope this makes sense.Last edited by Go1lum; 11-10-2009 at 01:28 PM. --Gol'
Reply:Thank you.Now how about the tool to measure with.  Does it look like I am using the correct tool?Also, here is a hand sketch of the situation.Regards,BennyB Attached Images
Reply:measure the leg size at the top of the pipe, and in the middle of the adjacent piece. Treat it as if it's 90. EDIT: i see the flange would get in the way for that. and your measurement tool looks like you are trying to measure the leg size not throat.Last edited by Go1lum; 11-10-2009 at 03:07 PM. --Gol'
Reply:Thank you for the update.  This was a big help deciding how to setup my checks I will do.
Reply:Hope you got the just of it. It's kind of hard to explain in words. btw the weld in your second picture by your measuring device looks like it kinda has some underfill. --Gol'