Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

Register Log in
  • Congratulations TugboatEng on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  1. Cockroach

    how to calculate weight applied to structure by flowing material

    You can also multiply the density of your grain flow with bearing load of the spoke and velocity of the flow squared to get the force exerted by the medium. Basic fluid dynamics, F = p A v^2 = kg/m^3 X m^2 X (m/s)^2 = N. Regards, Cockroach
  2. Cockroach

    Stress concentration of a 3-D ellipsoid

    I have done this before, using elliptical relieves instead of standard rounded fillets in the corners of stepped shafts. Usually 3:1 ellipses give the lowest concentrations of stress, about 25% less or so. Is this what you are trying to do? Finite element on the shaft is how I solved my...
  3. Cockroach

    Force of bolt

    Just look up Lifting Capacity for threaded fasteners in any decent book on mechanics. Or Google it, many engineering websites spell it out in detail. Regards, Cockroach
  4. Cockroach

    CV Joint (coupling) Question

    Google Rzeppa Joint. I have very good success reverse engineering one for use in drilling applications, oilfield, Western Canada. Regards, Cockroach
  5. Cockroach

    How to calculate Buttress Threads stress for a comparison to standard threads?

    I don't think it is that easy, the first sentence in the section on stress says it all. Thread stress computations are complicated! The Buttress is a tapered thread form and therefore, equations associated with shear and bending are not the same as those for a straight thread. Several studies...
  6. Cockroach

    Wire form calculations and formula

    Handle it like a cantilever beam with shear, bending, rotation and deflection. You can correlate deflection to shear in the linear range of the material by calculating the bending stress at the support of the cantilever. Regards, Cockroach
  7. Cockroach

    Cost calculation

    No, you approach the problem egronomically. Have a technician press on the piece repeatably for eight hours a day, five days a week. Correlate acceptance to rejection critia; what can go wrong? Define some level of acceptability between mating pieces and break out operator induced rejections...
  8. Cockroach

    Engineering drawing print/release/database system.

    Yes, I upgraded ProE to SolidWorks. That software took care of the issues you raised and solved a lot more problems than I had experienced to date. Perhaps you need a friendlier software package and support group who actually care about the end user. ProE boys just want to sell you the...
  9. Cockroach

    Threaded connections for Automatic air vent and Pressure Relief valves for Jet fuel service

    Would it not be a safety issue? Usually this is where I get the resistance. NPT forms are particularly weak in shear, any side load, wanted or unwanted, would snap the relief valve off at the stem. This would have a tremendous amount of safety concerns given your medium is a jet fuel. Often...
  10. Cockroach

    Tightening torque for Scoket Head Cap Screw

    Unbrako is a good reference. Regards, Cockroach
  11. Cockroach

    Bearing area

    Pardon me...OD is 1.352 inches or about 1 23/64 inches. Forgot the factor of safety to be 1.25 inches. Regards, Cockroach
  12. Cockroach

    Bearing area

    Using mild steel (43 ksi) typical of off the shelf tubing, I get an OD of 1 3/16 inches. This assumes your 24 kip pre-load with 8.5 kip external compressive load will give you a factor of safety of 1.25. As noted, you want to resist collapse in which case the pre-load would be lost...
  13. Cockroach

    Metric Thredolet

    A dime a dozen in Canada. Try any pipe supply house in Edmonton or Calgary. Regards, Cockroach
  14. Cockroach

    Help needed with a design

    You know what? I'm going to take this on and develop it. What is the required centre-to-centre distance for the thru holes (i.e. ears) and those of the bolts? Safe working load is 10 kips, but the design will be tested to 30 kips, FOS=3. I hope those set screw looking fasteners in the front...
  15. Cockroach

    maximun angle soybeam belt conveyer

    Basic physics. What is the angle of an inclined plane given a block of known weight subject to friction? Figure it out using a textbook example and comparing it to other known problems with solutions. Then make the inclined plane move at some prescribed velocity and ask the same question...
  16. Cockroach

    Calculate velocity of a spring loaded object

    This is a first year physics problem, you do it in one of those lab seminars on springs. It is not complex, finding iterative solution sets because there is a worry about standing waves translating through the spring. For God's sake man, this was solvable in Newton's day without computers...
  17. Cockroach

    Yield/Tensile to Shear Strength

    Energy of Distortion Theory, 0.577 X yield strength. Regards, Cockroach
  18. Cockroach

    Calculate velocity of a spring loaded object

    Yeah, I agree with Applico and TheTick. Manners have been horrible in this forum for quite some time now. Anyway, toy cannon scenario. Load a marble and compress the spring, trigger release. How far will the marble go? The range is dependent on angle of trajectory and muzzle velocity off...
  19. Cockroach

    intersection point of two askew cylinders

    In practice, I would solve it mathematically for the specific equations and orientation of each cylinder in 3D space. Problem is beyond the scope for this forum, you need to use multi-variable calculus and manifold theory in order to get what you are after. I suggest going to a mathematical...
  20. Cockroach

    Knurled bushing calculation

    The purpose of a knurl is to build up the OD of a piece intended to be an interference fit with another piece. As such, knurling is often used to fix a machining error in over turning a shaft. We're talking thousands of an inch over diameter in this case. I have seen knurls being used in...

Part and Inventory Search

Back
Top