The Great Ultrasonic Stack Joint Debate: Who should you listen to? (http://archive.plasticsdecorating.com/articlesdisplay.asp?ID=111)
by Tom Kirkland, Tributek
Assembly
April-May2011
Stud materials -
Steel
Branson
Metal welding companies?
Titanium
2018-07-23 Rinco, Gordon Hull meeting - all are Ti with broached hexed sockets. Unbottomed.
Kimberly-Clark (Stegelmann_Norman_(Kimberly-Clark)__US_patent_6841921B2_(2005)_'Ultrasonic_Horn_Assembly_Stack_Component_Connector'.pdf, col. 5, line 51)
Dukane -
Check Dukane dwgs to see stud hole tapping specs; also, joint machining specs (flatness, etc.)
Wedged stud? Check -
Kirkland (see http://archive.plasticsdecorating.com/articlesdisplay.asp?ID=111)
Jim Depuis (Linkedin.com)
dxf files on floppy disks
Hilscher -
bottomed stud? 5/6/2018 - Google couldn't find
S&M - Get stud torques. Same bottoming method as Branson?
Discuss -
Best to have stud secured in most expensive, least expendible resonator?
Tapping class thread - looser class is better for resonator in which the stud is not secured?
Spanner wrench fixture to prevent stripping spanner holes.
Required stud hole depths.
Osgood -
p. 213 - "An optimum choice for both strength and corrosion resistance is often the 316-type stainless in the 5 c condition (min Fty = 100,000 psi) ..."
p. 221 -
Threads heat treated after cutting "should not be considered for high fatigue applications."
Ref [183] - fatigue life of bolts as fn of root R and tensile strength data.
Sproat, R. L. - "Radiused-Root Threads - Are They Really Better?" --> Google couldn't find original
Branson - 'TL-8, Torque Wrench Kit'.pdf
Gives joint and stud torques.
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Herrmann Ultrasonics (https://www.youtube.com/watch?v=Ygd-CJnBLZo) - stud is inserted into booster rather than horn
See buc_40kHz_al_sn_horn__floated_stud.txt
.C.::FEA Gain Confirmation
The aluminum SŽN has been analyzed by FEA?SN\AlStud1, SN\AlStud2, SN\AlStud3, SN\AlStud4: same as current design, including compound radius, but front diameter = 0.340 instead of 0.360?.
.f.Figure˜?f???loss\stdmpl2.plt??Effect of Horn Stud on Relative Amplitude of Al SŽN Horn;? shows the horn's relative output amplitude as the gap between the end of the stud and bottom of the stud hole is increased. The greatest decrease in amplitude occurs just as the stud is removed from the bottom of the hole. This allows the bottom of the stud hole to "breathe".
At a gap of 0.024" (approximately 1/2 turn of an M8 stud), FEA indicates a relative amplitude of about 0.948. This essentially agrees with the measured value (0.942, calculated from figure˜?f???loss\stdampl1.plt?).
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Diogo Tubertini Maciel - "Characteristics of machined and formed external threads in titanium alloy"
Int J Adv Manuf Technol (2015) 79:779-792
DOI 10.1007/s00170-015-6858-z
https://link.springer.com/article/10.1007/s00170-015-6858-z
According to Zhang and Yang [37], titanium and its alloys
are widely applied nowadays, but their components are very
difficult to manufacture. This is due to their low elasticity
modulus, generating a friction torque that is seven times great-
er than in pure carbon steel. (p. 779)
However, it is suggested that only materials with high
ductility have great potential for manufacturing by thread
forming. Generally, there are materials that continuously gen-
erate chips when the traditional process is applied, which
makes them more suitable for the forming process [13]. (p. 780)
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Using undercut nut to get more even force distribution across bolt threads (Juvinall, p. 250, fig 13.18; Shigley, p. 250, fig 7-14)
deformed_stud_thread --> wave thread? Unbrako?
Threads
GFM thread study
GFM tip - reduced thd engagement (lengthened shank) to reduce thd failures
Taps
Tap with asymmetrical thds to get uniform thd stress in nut.
See SPs fastener book fig Iv-9, p. IV-9 (patented by Standard Pressed Steel Co); fig IV-16, p. IV-16.
Solidica
J thd test -- still going after ~417 hours @ 45 microns (Ray Opie email 4/26/2007, see Vertex folder)
R thd had failed within 27 hours (my notes 3/27/2007). However, bad machined thd surface?
Joint temperature measurements for Vertex & M2, unbottomed studs (my email of 3/16/2007 to Ray Opie) -
highest temps at stud joint rather than at node.
Unbrako --
Metric studs
Stud dias every 2mm (M8 x 1.25 (0.059"), M10 x 1.5, M12 x 1.75 (0.069") )
Lengths
M10 - 10mm min; 25mm & every 5mm thereafter
M12 - 12mm min; 25mm & every 5mm thereafter
End cone dia
M8 - 5mm (62% of dia)
M10 - 6mm (60% of dia)
M12 - 8 mm (67% of dia)
Stud hole dims (non-bottoming tap)
M12x1.75 stud
Ti horn
Use 35mm (15 mm into horn (8.5 thds engaged if no lead-in hole chfr), 20mm extending)
Hole depth - 19mm (allows 2 chfr thds on tap (3.5 mm) + ~1/2 thd (0.9mm) to back out stud from bottom)