Calculation of bridge width for RCB-7.22 in TEMA standards

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After carefully reviewing the RCB-7.22 table for bridge widths in the TEMA standards along with the accompanying annotations, I have the following question: 1. Is it true that if the thickness of the tube sheet does not exceed 152.4 mm, interpolation calculations must be carried out using the table? 2. If the value exceeds 152.4 mm, is the formula for calculating the minimum hole bridge width given as the center distance between the tube holes minus the tube diameter minus the drill bit offset (2*drill bit offset tolerance*tube sheet thickness + 0.76(0.51))? However, does this formula yield a value that is too low? Comparing this with the formula in GB/T151-2014, which is the center distance between the tube holes minus the tube diameter minus the drill bit offset (2*drill bit offset tolerance*tube sheet thickness/tube diameter + 0.76(0.51)), is there also a formula for calculation according to TEMA?