Desertfox,
here is the link for the embedment test snaps.
http://img521.imageshack.us/img521/7991/untitledps3.png
Top 2 snaps are the 3/8 perimeter took to proof load
bottom 1 is the 7/16 taken to proof load
does these pics show any signs of embedment? sure we lost paint under the washer...
Dimjim,
Yes the hole diameter increases uniformly from under head of the 7/16 bolt to the bottom.
Under the head ID is 0.48 in and the ID of other side of the hole in the picture(3pf9) is 0.58 in. OD is 0.88 in. The depth of the hole in the gear case is 2.71 inch
Desertfox,
Yes I can do some testing to see any embedding witness marks. I will do that on monday.
Dimjim,
I will get you the dimensions of that hole on monday for sure. Thanks a lot.
Desertfox,
when u said bolt 2 and other side bolt would take the max external tensile load, are u sure about tensile load? I thought it would be more shear loading because the water flow or the water pressure is acting perpendicular to the bolts axis here right?
regarding the tapered face, if...
Thanks Desertfox.
Dimjim,
All the surfaces(exhaust housing tapped holed surface, gear case bottom surface) are really flat (no raise) except for the 3/8 perimeter 4 bolts on the top side of gear case where the bolt head/washer lands. That surface is little raised and has a draft angle of less...
Dimjim&Desertfox,
More pix before paint
http://img254.imageshack.us/img254/118/untitledth3.png
http://img386.imageshack.us/img386/3924/untitled2ik5.jpg
http://img246.imageshack.us/img246/7451/untitled1nd5.png
http://img112.imageshack.us/img112/7981/untitled3pf9.png
Dimjim,
Thanks and reg the insufficient info, yes I agree it will be frustating for some one who is trying to help.
Here are the pics of assembly for better understanding. I can get different angle pics if you need.
http://img504.imageshack.us/img504/9900/view2vi6.png...
Cory,
I am really sorry for long threads.As I mentioned earlier I am brand new to this fasteneing field (for short term projects) and was seeking help.I hate to be new. Thanks for understanding and helping.
Dimjim,
Yes they are tested, but I need to rquest our supplier for the data.
but even with 160ksi for a 3/8 bolt we are safe. I got LE of 0.68 in for 160ksi which is still less than our current le values for 3/8 bolts
the problem is only with the 7/16 bolt regarding the LE
yup I agree, we will play with torque for sure.
anyway I will et you know how consistent things show up after we do some experiments with dry bolts. and if we are consistently holding the clamp spec then we are good to go.
Dimjim and Desertfox,
My calclulations using the formula in the link I posted gave
Le = 0.515 in for 3/8
Le = 0.621 in for 7/16
I used
tensile strength of bolt = 120ksi for both bolts
tensile strength of nut = 42ksi for both
n = 16 for 3/8, n = 14 for 7/16
minimum OD of bolt threads =...
Dimjim Thanks for the quick response, I got the page from "An introduction to the design and behaviour of bolted joints" by Bickford. You can also refer "The handbook of bolts and bolted joints" by Sayed Nassar and Bickford.
What did you take for tensile strength of the bolt material? Ultimate...
So you guys are saying that from design point of view we got 2 issues already on this joint
1) embedment issue
2) insufficient LE issue
These two "might" be the causes for my loose/missing bolts.How can I prove embedment in our lab? Any easy and quick method?
I think after our dynamic testing...
Dimjim,
So what do you think from your calculations? We are short of Le on 7/16th bolt and perimeter 3/8 th bolts? If so how much Le do I need on both of them?
By any chance could you please upload your calculation because I wanna see the numbers you guys used for minimum OD of bolt threads and...
