In the saddle verification section of SW6, how can the excessive diameter of the drum opening be addressed?
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This post was last edited by WallaceLee on 2022-7-19 at 15:50. There is a horizontal tank with a diameter of 4000 mm, and in the middle of it is a drum with an inner diameter of 2200 mm; the material of this drum is a composite steel plate made of Q345R and S31603. The distance from the sealing surface of the top flange of this drum to the center of the tank equipment is 8520 mm. The wall thickness of the cylinder at the section connecting this vessel to the drum is 30 mm, while the cylinder thickness in other sections is 22 mm. As shown in the figure above, there is a pair of vessel flanges in the middle of this drum; the thickness of the lower section of these flange-mounted tube sections is 24+3 mm, while the thickness of the upper section is 14+3 mm. Currently, SW6 is used for saddle checking; the wall thickness of the cylinder is set at 22 mm, and that of the steam drum at 14 mm for the calculations. However, SW6 indicates that the openings in the auxiliary equipment are too large, making it impossible to carry out the calculations. How can this problem be solved? Was the selection of the drum wall thickness and shell wall thickness correct during the verification process?
The saddle area is calculated based on concentrated loads, while additional local stresses are considered for the areas with openings
Your ribs are way too compact… I suggest adding a reinforcing ring at the opening
In fact, even without a reinforcement ring, the checks for internal and external pressures are both satisfactory
The reinforcement ring here is not mainly used for strengthening holes, get it?
Its function is to distribute the stress concentration caused by the stiffening plates and increase the effective area of the perforated nozzle… In any case, it is beneficial for the local stresses in the cylinder most of the time
The gravity of the drum and pipe stresses will generate significant local stresses in the areas where it is connected to horizontal equipment, making conventional calculations ineffective. It is recommended that SW6 undergo routine horizontal verification; the weight of the steam drum should be included in the total weight of the equipment, and reinforcement rings as well as at least 10 support ribs should be added at the connection points. If the supervision department insists on having a stress analysis conducted here, then analysis and design will be carried out.
Given that the technical requirements for this device do not take into account the take over load, I believe it is unnecessary to install a reinforcement ring specifically
Given that the technical requirements for this device do not take into account the take over load, I believe it is unnecessary to install a reinforcement ring specifically