Calculate Beam

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If it is a beam used temporarily for something like lifting, deflection is a particularly important criterion, unless the deformation is so large that it causes other negative effects. The most important thing is that we do not have any collapse of the cross-section, and the first requirement is that we have good safety against plastic deformation. But for many cross-sections, there are also stability requirements that need to be checked. So I wouldn't use the beam in that way. I don't think one should compromise on the safety factor; there are certainly uncertainties with it.

Apparently, I will need to get a stronger beam.

 

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Check boverket

Don't question if you don't know, a good motto in life.

 

[Plupp 618974]

I join the group that hasn't lifted with this beam. If hlph has calculated correctly, the tension is way too high. When we've calculated lifting devices, we've calculated 3-5 times the rated weight compared to float, in addition to buckling analyses, maximum deflection requirements, and in some cases, natural frequency. If Kane has calculated correctly, my opinion is that the deflection is also too large.

The economic consequences are significant if there's a mistake here. Perhaps someone is managing the load, posing a risk of personal injury. Even if your beam might work for the purpose, "might" is not good enough. Find a rated lifting beam!

 

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I count myself among those who have not lifted with this beam. If hlph calculated correctly, the tension is way too high. When I've calculated lifting devices, we've calculated 3-5 times the rated weight against float, plus buckling analyses, maximum deflection requirements, in some cases even eigenmodes. If Kane calculated correctly, my impression is that the deflection is also too large.

The economic consequences are significant if something goes wrong here. Perhaps someone is standing and guiding the load, which also poses a risk of personal injury. Even if your beam might work for the purpose, might is not good enough. Find a classified lifting yoke!

Yes, that's how it should be, a classified lifting yoke exists, so it will be necessary to acquire a significantly stronger beam.

 

[Granngubben]

A square steel tube, 80x80x3.6 or larger, should work if it concerns 500 kg and a 1.8 m span.

 

[Plupp 618974]

A square steel tube, 80x80x3.6 or larger should work, if it's about 500 kg and 1.8 m span.

Becomes very high stress even in that cross-section.

 

[Granngubben]

There will be very high tension even in that cross section.

Oh, I don't think 85 MPa is a very high tension, there's no risk of buckling or any other instability phenomena in a square tube.

 

[hlph]

Oh, I don't think 85 MPa is a very high stress; there's no risk of buckling or any other instability phenomenon in a square tube.

There should be enough margin. For lifting beams, which one could consider this as, you need a factor of 2 against plastic deformation and a factor of 3 against collapse. You don't need as large safety factors as you have for lifting devices, like shackles. But it is important not to have any local issues when attaching a lifting device. That is likely to be the determining factor.

 

[spikplanka]

If the beam bends, it is necessary to ensure that chains, etc., cannot slip off.

 

[Plupp 618974]

Oh, I don't think 85 MPa is a very high stress, there's no risk of buckling or any other instability phenomena in a square tube.

You're right, I initially got it to double. You shouldn't calculate strength with a mobile phone lying horizontally. 😂

 

[scorp1on]

I don't have my old formula collections nearby, but it seems to result in a 5 mm deflection if it's positioned that way. So it should be OK.

A bit too high. If you have the load in the z-direction, you get bending around the y-axis, and I then calculate the deflection of the point load (on a simply supported beam) to be 0.8 mm and the beam's own weight to be 0.02 mm.

EDIT: Saw that the original poster intended to load the beam in the y-direction, that is, over the z-axis.

 

[Kane]

EDIT: Saw that TS would load the beam in the y-direction i.e., over the z-axis.

What calculated values do you get then?

 

[scorp1on]

There should be sufficient margin. For lifting beams, which could be considered here, you need a factor of 2 against plastic deformation and a factor of 3 against collapse. You don't need to have such large safety factors as you have on lifting gear, like shackles. But it's important to ensure there are no local unpleasantnesses when attaching a lifting device. That is likely what's determining the design.

What calculated values do you get then?

Just over 5 mm as you wrote

 

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It became a slightly stronger beam, the lift was done with lifting straps and a chain hoist. The lifting/lowering was very successful and everything went as planned. The stove was pressure tested and approved today.