For taking out or sizing test coupons of steel castings you may also refer DIN EN 1559-2. However, test coupons need to be agreed with customer, sizing of coupons dependent upon chosen / required final size etc as per previously mentioned standards. In the end, why not directly approach a steel...
Hello OP,
do I get it correct that these bolts have already been torqued into place once, then disassembled, and are now re-used?
Pls. check, to what level / standard the original torqueing has been done: to yield (70 or 90 %) or beyond yield. If the second, theses bolts are imo as a rule not...
These positioners transmit a heavy horizontal force-couple into the rails, as well as their vertical g-forces. Requirements on positioning accuracy must be met. If drive is a rack & pinion, geared wheels-to-rack position requires sufficient stiffness.
Roland Heilmann
Ck75 means it is a cold rolled spring steel.
Could you verify your part being made of that material? Else, imo you need to contact a good supplier to make an assessment of your application / the material used.
Roland Heilmann
Air/space tech providers of the Shuttle program might be a contact, as liquid H2 was part of the fuel and mass a critical parameter, ie high strength materials had been used.
Roland Heilmann
3 pts of support: statically determined, you know where you are with the loading from basic mechanical calc.
4+ pts: statically indetermined, its more difficult to calc. or you build larger than strictly necessary. However: it is more stable, as the footprint is larger, there's a longer way for...
Quote < Now let's swap the bolt with much larger one, and preload it exactly to the same amount of case#1 > unquote
The larger bolt, not being preloaded to its proper percentage of proof strength, cannot be considered secure in sense of loosening / getting untightened.
You'll have to take care...
Such scrapers / cleaners are common to fulfill the functionality you require.
With ash, wear on belt and scraper blades as well as material buildup / sticking may be issues.
Just contact that supplier (its a well respected one in the industry), describe your needs, they'll at least point you...
With such components of existential importance to the system and without redundancy, and especially when lives are at risk:
Rules should require a pre-test in a safe working environment, step-by-step increase of load, thorough check for cracks prior and after.
But I don't know whether this is...
Yes, there's much more detailed investigation to be found.
Actual distance from rim-pierces-compartment event to derailment was ~6 km, almost 2 minutes time (wiki)
And yes, the manager was obliged by regulations to first assess the situation.
However, what would one decide to do if a really big...
NASA does safety messages on various incidents, always with an edge towards everyday's engineering works.
This one is special to me:
Link
as it conveys, how human decisions influence the course of acion.
I remember that time, the incredulous facts that the maintenance workers didn't heed the...
there's similarity to brake design: brake disc and brake pad.
so maybe that's a place to dig.
afaik, the thermal conductivity coefficient is established in tests.
a FEA thermal modelling might add insight, for a specific case.
Roland Heilmann
well, this is a forum, an OP rolls a dice in some way and let's roll it to the benefit of ... all.
there's nothing more far off from engineering like an opinion about an opinion, perhaps its better to stay with the basic facts.
i appreciate the question of the OP, to know how to ask a question...
The cracks are like equally distributed on the inner surface: Any more cracks subsurface further within the body?
Are there handling operations involvimg a turning up of the ring, or even a sitting on its outer diameter?
You say, you cut rings from cylinders:
Then, due to ring form (inner vs...
I do so much grieve all these people, their relatives, friends. My sincerest condolences to them.
To find out, what happened and how to prevent something similar:
Put faces to Sparwebs (& others) questions, form a team which is not shy to stand up out.
Demand competent and involved partners in...
from a practical p.o.v.
Looking into some applicable standards:
e.g. FEM 1.001 sec 4.1.3.1 the limit cycle no. to require a fatigue investigation is 8000. That's less than 10k as per EC.
e.g. FEM 2.131 sec 3.4 sets this limit to 2.5 10exp5.
The accompanying wording is that the fatigue loads...
This concerns railway material, there should imo be some specific standard to applicable frictional coefficients.
If there is not, then similar standards might help: FEM 2.132 / 2.133 give applicable statical and kinetical c.o.f.
This need to be approved by the authority concerned.
As friction...
