What is the impact resistance of CF like in this form?
My only experience is with thin walls (bike frames & paddles) but I noted in a video on YouTube by dallymd that a weighted mooring line has been thrown out to the sub 15:55 timestamp) and impacted the vessel.
In this case the weight hit...
Hello Guys,
Thank you for your input, at the time I pushed through taking advice from above.
Just a quick, and belated thank you for the advice rendered.
dhengr
Thanks for the food, it has definitely inspired some thought!
Central lifting eyes are in line with CoG.
Agree that structure needs to be investigated, I will be making this recommendation.
With regard to manufacture, I will have to take these points on board, the lugs are currently...
Hi Mike,
My apologies on that I should have marked the CoG onto the sketch,
The two center lugs are in line with the CoG which is located roughly in the center - Pretty much 1.85m down the 3.7m length, and very slightly offset on the width dime, ~0.85m on the 1.8m width
Just to note the red...
Some useful references:
An introduction to design and behaviour bolted joints Bickford - Has section on gaskets
Flexitallic Gasket Design Criteria -
KLINGER do a software program KLINGER expert that will advise this - believe if you contact they may be able to assist (thought don't quote me...
Hello All,
Thanks for your continued input,
Lomarandil - The central lugs are in line with the predicted COG. The I beams are part of the duct structure, originally to support two overhanging platforms, that are now being installed separately.
CANPRO -
In my sketch the green beam...
Hello Lo
I've attached a sketch for reference, but understand the lifting from center should be acceptable - however there will be increased stresses in the duct structure itself, that need to be checked out.
Thanks for your thoughts on this matter
Just for reference I've attached a sketch to show the required lift.
Impression I am getting is that 2 point center with stabilising strops (non load bearing) to 4 corners would be acceptable.
Key check is to ensure that the structure of the ducting is sufficient to take the increased loading...
Hi,
As others have said identifying the K factor, or individual friction factors (thread, underhead etc) plays an important part in in determining the applied preload.
The attached shows the the rough method to determine thread shear, and some other items you may want to consider such as...
Hello All,
I am hoping to draw on someones expertise on lifting ductwork.
I have a piece of duct work to lift offshore ~ 3.7m in length, 1.8m wide, and 1.2m deep: Mass ~1000kg, which for intents and purposes can be treated as a cube with a reasonably central COG.
My original design utilised...
Hello All,
I am hoping to draw on someones expertise on lifting ductwork.
I have a piece of duct work to lift offshore ~ 3.7m in length, 1.8m wide, and 1.2m deep: Mass ~1000kg, which for intents and purposes can be treated as a cube with a reasonably central COG.
My original design utilised...
Hi Random,
Thanks for the response, I've now completed my calcs and come out with an answer I believe to be on the side of conservative. The approach I have taken has been to:
Use the approach outlined by the roymech, blodgetts, and shigley site for assessing shear in the weld.
Assess the...
Hi All,
So some positive progress my end, I have now worked on a bit further and calculated out the attachment strength in the plate that the lug is welded to, and m satisfied with this part.
The point I am stuck on now is how to calculate the attachment strength of the weld to the circular...
Hello All,
I am looking into a welded lug for an application that will be subjected to an end load. The lug itself is circular in cross section and welded to a flat plate.
After reviewing my copy of Shigley, and looking through the forum, and coming across a number of interesting threads, in...
Is my understanding that a U-2(g) design is effectively a design from first principle/Roark/similar such reference applying the same rules for max allowable stress as specified in UG-23/ Mandatory Appendix 1 of BPVCII?