taper stud / hole strength
taper stud / hole strength
(OP)
I ran into a problem that need to use a 1:10 taper stud / bore connection to transfer loads, the smaller end of the taper is ~1.0" and the entire engage length is 1.125".
the stud is made out of hardened steel and material (cast iron, grade, etc.) on the female part is yet TBD.
could someone recommend a calculation method to estimate the joint fatigue capacity based on a certain loading?
many THX in advance
the stud is made out of hardened steel and material (cast iron, grade, etc.) on the female part is yet TBD.
could someone recommend a calculation method to estimate the joint fatigue capacity based on a certain loading?
many THX in advance






RE: taper stud / hole strength
RE: taper stud / hole strength
The taper stud is conical shaped, so as the hole on the mating female part. Very typical configuration if you've seen a tie rod assembly used a lot on automotives.
RE: taper stud / hole strength
RE: taper stud / hole strength
Yes I have started looking in the valve pdfs etc. However there maybe something simpler out there, mechanical formularies etc that I will be looking as well.
RE: taper stud / hole strength
RE: taper stud / hole strength
You can follow also the goodman method following fig. 2.2 at Roark's 6th ed (page 31) where you can extract the maximum stress range (reversal) when the average stress stays at some value. That is, you identify your average stress, then looking at the Goodman chart you identify how much you can deviate for that. This may or not suit your application. To trace the Goodman chart you will need to know sigma e, the endurance limit at complete reversal of stresses when the average stress is zero. This ranges for steels between 35 to 60% of sigma u ultimate (limit) tensile strength (see that at Pilkey's) and not to surpass 784.5 MPa.
Still to look at the mechanical formularies.
RE: taper stud / hole strength
Again, I think the welding/bolting forum, ME-material forum, or Automative Engineering forum is better place to seek help for this special application, which is rarely seen in Civil-Structural world if ever.
I believe fatigue is influenced by tightness of the connection (pre-load) as well. Good luck.
RE: taper stud / hole strength
Anyway, even if the Goodman chart and more accurate analysis should give bigger allowable range of stresses, the wedge is really very steep, even more than a typical spear, so I think the estimate as inferred from AASHTO should not be much off-the mark... it might be even optimistic.