Hi,
This is a relatively simple - but pivotal - query. How do we (or don't we) take into account the presence of longitudinal welds in continuous ERW members, like rectangular hollow section, circular hollow section, etc?
What about in fatigue applications (as my specific case is)?
I don't...
I have a part which is intended to sit in a jig that restraints it on all 6 degrees of freedom, with only the necessary and sufficient points. This is required for part function, as it is manufactured on a jig, tweaked on the same jig, QC'd on an identical jig, then installed with another...
Hi,
It's a fairly common occurance in my work that 4140 quenched and tempered shaft, when machined to reasonably precise tolerances (e.g. 0.1mm TIR over 500mm, for a Ø120mm shaft), needs to be 'rested' for 24 hours or more between the last few passes on the lathe, to let it distort, so that...
For mostly curiosity, but at this stage also the preservation of sanity, there is an ongoing discussion in our office on why we see weld on pad eyes/lifting lugs with splits in them. See image below:
We can speculate some minor decrease in certain stresses (e.g. contact stress reduction as...
We have a product that has historically used a semicircular surface as a cylindrical datum feature to define an axis. This semicircular surface rests under gravity onto a round bar of similar diameter that acts as the Datum Feature Simulator in a checking jig.
In a new iteration of the product...
Hi all,
This comes from a mech eng trying to understand a structural engineering calc and why it contrasts so hard with mech engineering calcs. Typically when I analyse a bolt in a hole near the edge of a steel plate, based on sources such as Rourkes, Shigley's, and Machinery's handbook...
This seems like an extremely elementary question but I haven't been able to find anything explicit on it.
I always thought it didn't matter which view you place your FCF or basic dimensions on (other than for clarity), but I'm coming across a specific problem with that thought (axis parallel to...
Hi all,
Our production engineering has designed a hand tool that significantly improves a process speed, but by its design, it has an 0.8mm thick x 5mm long cantilevered section with a stress raiser on one side, placed under unidrectional bending. Sketch attached.
The stress raiser is on the...
Hi all,
I have found nominal external circlip groove dimensions at various sites, such as this one: http://www.circlips.com.au/contentblank.php?sec=products&sec2=circlips&sec3=d1400 , which I assume are valid and come from DIN 471 (which I don't have).
I typically use the above dimensions in...
Hi all,
I am by no means a materials scientist or materials engineer so I hope that this is not a silly question.
We are reverse engineering our own product, as the material (a glass filled HDPE) was blended in another country by a company that wouldn't give us much by way of datasheets.
The...
Hi all,
I have a fairly simple problem I think, but I am new to this and I think I am missing something basic.
I have a simple tube that I am trying to control the length of. Its ends are cut to a certain perpendicularity to its own axis (I have a good set of datums that allow me to define a...
Hi Everyone,
I'm a relatively young engineer in a relatively small manufacturing company. I have always considered myself more of a technical engineer but I recently have been told by my higher-ups that I am going to have to start managing people more and more in my career, which is going to...
Hi everyone,
I have a reasonably long fabricated shaft with a bearing mounted to each end. The critical design constraint being that these mounts are aligned roughly coaxially (Ø1mm) and quite accurately parallel (2 minutes of arc). The mounts are welded on to the shaft so the welding...
