Arrangement method of tubes in a shell and tube heat exchanger

3.3 Arrangement pattern of heat exchange tubes and tube spacing There are four standard patterns for arranging heat exchange tubes. Arrangements of equilateral triangles and angled equilateral triangles are suitable for situations where the shell-side fluid has little fouling and no mechanical cleaning is required. Arrangements of squares and corner squares facilitate mechanical cleaning between the tubes, and are generally used in situations where the tube bundle can be removed for cleaning between the tubes. On heat exchange equipment with a small diameter, there is also a concentric circular arrangement. This arrangement is more compact; it contains more tubes than the triangular arrangement, and the tubes are evenly distributed near the shell, making it less likely for the medium to take short circuits. Regardless of the arrangement used, the distance between the outer wall of the outermost tube and the inner wall of the shell should not be less than 10 mm. The distance between the centers of two adjacent pipes is called the pipe center distance. For the pipe center spacing in arrangements of equilateral triangles and squares, it is generally taken as t >= 1.25d0 to ensure sufficient strength between the pipes during expansion. For columns arranged in a square pattern, a 6mm cleaning passage must be ensured to facilitate cleaning between the tubes.

1. Arrangement methods: 30 degrees, 45 degrees, 60 degrees, 90 degrees, as well as circular arrangement. 2. The arrangement method has nothing to do with the distance between the tubes; once the tube diameter is fixed, the spacing is also fixed. Generally, t >= 1.25d0 – for example, 19 corresponds to 25, and 25 corresponds to 32