DNV 2.7-1 Fork Pockets 1

[engpes]

In calculating the shear area for DNV2.7-1 container fork pockets, can end plates mounted to the sides of the bottom rails be accounted for in determining the shear area?

The code gives examples of adding shear plates above the bottom rail and fork pocket. Can they be added to the side of the bottom rail (see attached sketch).

Also, should the fork pocket loads be based on a load factor of 2.5 or 1.6 for the fork shear calculations. The code is somewhat ambiguous on this

Thanks in advance.

 

[EngineerTex]

1) If you have supporting calculations to show that the doubler plates that you are adding will be acceptable, then you should not have a problem. But the best way to be sure is to ask one of the surveyors in the DNV office which will be handling the design validation of this container. You could very easily run into a problem where 95% of all of the surveyors would be absolutely fine with it while the one guy you get to review your calcs says no.

2) It is recommended practice to have the bottom of the forklift pockets at least 2 inches off of the ground. When the containers are moved around in a gravel-paved yard onshore, they will pick up gravel and then later start dropping rocks on people when the crane handles it offshore. Some platform operators will not allow load out at the dock of containers which do not comply with this. At one time, I had thought that the DNV rule stated this, but when I was challenged on it, I couldn't find it. Regardless, it is still a good idea to keep the pockets at least 2 inches off of the ground.

3) I don't have the spec here (at home) right now, so I can't address the load factor spec with certainty. However, the 2.5 is for dynamic lifting and I don't think anyone would consider a forklift lift to be a dynamic lift. I would think that it should be 1.6, but that's another question that you should get answered in writing from your surveyor at DNV.

Engineering is not the science behind building. It is the science behind not building.

 

[engpes]

Can the cross sectional area of the cover plate be utilized in calculating the available shear area? Or only the tubing web?

This is assuming my 3/8" fillet weld is sufficient.

Thanks.