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Dear seniors, I am a student majoring in Process Control, class of 2016, about to graduate. I have encountered some problems with my graduation project, so I am here to ask for your help! What is being designed is the final condenser (U-tube). The issues are as follows: 1. The equipment dimensions specified in the design document are 800*3500, yet the length of the heat exchange tubes is only 3500; do the equipment dimensions not include the end caps and tube boxes? Moreover, the length of the cylinder is 3500, and the length of the tube is also 3500 – so how can the U-shaped tube be bent? What is the length of the straight pipe? (I checked; the length of the heat exchange tube is only counted for the straight section.) 2. There are two values for the overall heat transfer coefficient in the table of process calculation results in the design document: 799 for clean conditions, and 441 when using the alternative value. I remember that when performing process calculations, the heat transfer area is estimated using the formula Q=KA△t; I tried using both values, but I couldn’t get a corresponding result. (The heat load is 2950 KW, the average heat transfer temperature difference is 53.5, and the designed heat transfer area is around 124.) If calculated using the heat transfer area for each case, one value is over 60, resulting in a margin of almost 100%, while the other case has no margin at all). 3. The pipe diameters listed in the design documents are all 1″; I checked online and found that this is an inch unit. Should 1 inch be represented as 25.4 units in the drawings? After all, it’s my first time coming across a manual like this (the teacher said it’s used in actual design work), and I have many questions, so I’ve come to ask the more experienced ones for advice!