Are the process parameters provided to the design institute in this way?
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Some time ago, our company needed to add a heat exchanger for process gas/liquid ammonia in order to carry out process modifications. Since we did not have the necessary design qualifications, we approached a qualified small design firm. That firm requested that we provide the process parameters, namely various parameters related to the cold and hot media used in the heat exchanger. Therefore, I provided the design institute with the components of the process gas and liquid ammonia, the proportions of each component, their densities, operating pressures, operating temperatures, flow rates of the media, the external environmental conditions under which they are used, as well as our estimated area, the reference size of the pipe openings, and the approximate locations of those openings. However, the design institute requires us to provide information such as the material of the tube bundles, the material of the shell, the dimensions and spacing of the saddles, a cross-sectional diagram of the heat exchanger, the distances between various pipe connections, the number of heat transfer tubes, the heat transfer amounts for each section, the heat transfer coefficients, as well as the spacing and quantity of the baffle plates. I have a question for those in the design field: when providing parameters for manufacturing processes, do we need to specify the various dimensions of the equipment in such detail?
From the data provided by the expert, it seems that you have already chosen the equipment, but due to a lack of the necessary qualifications, you had no choice but to hand it over to the design institute. If the design institute selects the equipment based on calculations and designs, then there is no need for you to provide the structural dimensions of the equipment. It is precisely because you have already selected the equipment that the design institute needs to conduct calculations based on the physical properties, operating parameters, and structural dimensions of the equipment, to determine whether your choice meets the process requirements. You’re looking for a small design firm, but I think they are quite responsible. This post was last edited by wsts00100 on 2008-1-28 15:54.]
If that’s the case, it would be better for you to design it yourselves first and then have a design institute review it and issue an approval stamp
By a design institute, it means that after you design it yourselves, you have it reviewed by the design institute, which then stamps it to give its approval.
Without the necessary qualifications, they don’t have the various format documents, forms, labels, etc. required for ISO9000 certification; it is the design institute that must create the drawings based on their ideas and affix seals to them for them to be valid. The data provided includes information such as the size and direction of pipe openings as well as the material of the pipes – isn’t this exactly what is used to create installation drawings? This post was last edited by wsts00100 on 2008-1-28 00:26.]
Actually, after providing these, just ask them to produce the drawings and sign them.
If it’s the design institute that’s handling it, there’s no need to provide such detailed information. Generally, it is sufficient to specify the properties of the process medium and the operating conditions. For equipment that is modified or added, dimensions such as pipe connections, saddle positioning dimensions, or the diameter and length of the cylinder must be provided to facilitate installation
The most crucial aspect is the selection of equipment (manufacturer), which has already been decided by Party A; that’s why such detailed data is needed.
I understand what you mean, big brother. The parameters are provided by your factory, while the design institute is responsible for designing the equipment (they don’t deal with the manufacturing process). So their requirements are valid; since your factory is now taking on the role of carrying out the process design, you must provide them with information such as the material of the heat exchange tubes, the material of the cylinder, the dimensions and spacing of the saddles, a cross-sectional diagram of the heat exchanger, the distances between various pipe connections, the number of heat exchange tubes, the heat transfer amounts, the heat transfer coefficients, as well as the spacing and quantity of the baffle plates. Unless you ask them to use their processes for your design (based on your operating conditions), and have their equipment be used to design the structure, in which case you will have to pay extra.
Heat exchangers have been standardized and serialized, so there is no need for equipment specialists to carry out further design work; the process engineers can simply select the standard models based on the calculation results. Special equipment designed for specific purposes.
Personally, I think it comes down to how much money your company pays the design institute; the more money you give them, the more work they will do for you. On the other hand, if the design institute’s quality is poor, what’s the point of giving them anything at all? It really just remains to get it stamped. It’s best to clarify this matter during the negotiations.
I work at a design institute; given the situation you described, I would also ask you for these parameters. These days, many organizations (especially those with a certain scale and technical capabilities) often develop their own solutions, not just individual devices, but also certain processes and piping systems. Because they think that with years of experience behind them, there surely won’t be any problems; turning to your design firm is just for them to get a signature. In fact, this approach is not worth promoting. Perhaps the technical issues aren’t that serious, but in most cases their understanding and familiarity with the standards are clearly inadequate. Many times, they show disdain for the design drawings we produce, often asking why it has to be done this way, as it is costly and time-consuming. But these days it’s not enough for what you make to be useful and cost-effective; it must also comply with various standards. As long as the design institute requires signatures and stamps, and under a lifetime responsibility system for design work, no one would take the risk of signing carelessly. Of course, it needs to be calculated. If you only provide the basic requirements and leave it to the design firm, they won’t ask you for those things!