Discussion on heat exchanger standards

It is better to design it according to the actual needs of the device; standard solutions cannot take everything into account

Previously, a standard heat exchanger was available for selection; nowadays, designs are generally custom-made to better meet customers’ needs

Sub-topic: 1. In terms of safety, it is a pressure vessel and must comply with relevant standards ； 2. In terms of heat exchange technology, relevant standards are recommended but not mandatory. These standards are set for laypeople; you don’t have to follow them. In fact, these standards are exactly what you mentioned: an astonishing level of wealth ； 3. Some of the requirements specified in the standards are also highly unscientific; for example, the formula used to calculate wall temperature is fundamentally incorrect. Of course, it’s also a recommendation standard; you don’t have to follow it ； 4. The question raised by LZ is very meaningful. On this forum, many people use the rudimentary algorithms recommended as standard to criticize others’ more advanced ones. Motto: Standards are the bottom line of technology, not the standard of truth.

At present, the only heat exchanger manufacturing standard that I am familiar with is GB151, which is a manufacturing standard. For standard heat exchangers, only the heat exchange area is specified as standard. However, in various industries and enterprises, there are many different types of materials used, and the heat exchangers we produce come in a wide range of materials; the diameters of the heat exchange tubes vary, as do their lengths, and the connections between these tubes also differ. I’m not sure how to choose a standard heat exchanger in such situations

This post was last edited by wiseboy on 2012-2-28 10:14, version 1. For strength, etc., you need to choose the pressure vessel standards ； 2. For structural dimensions, you don’t have many options; there are only a few specifications for pipes available, and those are also standard recommendations – you’re not required to follow them ； 3. You can use a wide range of sizes; there’s no need for any standards – as long as your heat exchange calculations are sound ； 4. Heat exchanger standards are primarily established by the petrochemical industry, and in terms of dimensions, they do not cover other industries. Therefore, software like Them was initially designed according to standard specifications, which made it unsuitable for use in other industries. Only after non-standard pipe sizes were added could heat exchangers for pipes of any size be calculated, thereby enabling easier use in other industries.

It is generally a custom-designed solution, with standard specifications appropriately adopted based on the conditions within the factory

In any case, whether it is designed or manufactured, it must be above or equal to the standard; falling below the standard makes it completely unusable. This is a national condition as well as a requirement for safety.

I would like to ask the moderator for any recommended standard books on thermal calculations for heat exchangers!

It’s like buying clothes: custom-made items always fit better than those bought ready-made, but they cost more, as ready-made items are produced in bulk while custom-made ones are unique. By the same logic, heat exchanger standards are the requirements that must be followed during the design and manufacture of heat exchangers, whereas personalized designs belong to the custom market.

The “standard heat exchangers” mentioned by the poster can be understood in several ways: 1) standardized heat exchangers from the JB/T4715 series, such as fixed-tube-sheet heat exchangers, U-tube heat exchangers, floating-head heat exchangers, air-cooled heat exchangers, and spiral-plate heat exchangers. 2. Heat exchangers for various mature processes (such as refining, coal coking, and other such processes). The area of such heat exchangers is generally fixed, and as time goes by, the users purchase heat exchangers with a larger heat exchange area; this explains why heat exchangers in China have a large margin of capacity. The standards for heat exchangers can be understood in several ways: 1, series-based standards ； 2. Design, manufacturing, inspection, and acceptance standards ； For shell and tube heat exchangers, the standard in China is GB151, which belongs to the Type 2 heat exchanger standard; in the United States, it is TEMA, which also falls under Type 2. China’s GB151 standard was formulated with TEMA as a reference. It cannot be said that there are no standards for heat exchangers abroad. When selecting heat exchangers, we generally aim to follow the JB/T4715 series standards; if a larger margin is used, it is possible to reduce the length of the tubes, but this then violates the standard requirements.