Key considerations for bespoke heat exchangers
Bespoke heat exchangers enable design and manufacturing teams to take into account the unique requirements of your process and industry. By designing custom heat exchangers, everything from the heat transfer efficiency to the cost can be closely controlled.
If you need a bespoke heat exchanger, there are some key things to consider.
Heat exchanger type
A bespoke heat exchanger design must begin, of course, by understanding what type of heat exchanger is correct for your application.
Because it can be customised, each type of heat exchanger has a wide range of suitable applications. For example, a shell and tube heat exchanger has numerous configurations that can make the product suitable for chemical industries through to marine and defence sectors.
For example, our CACW coolers will be used in renewable energy plants – such as our recent work with a biomass-fired power generation facility in Fukuyama town – and are already in use in frigates and submarines. Each application requires unique design considerations to make the CACW cooler suitable for its purpose.
It’s in the design of the heat exchanger that some of the key considerations come to the forefront. We begin with data from the client to calculate the best configurations according to the product’s application.
There are many considerations that feed into the design of a bespoke heat exchanger, some of which are detailed below.
We begin with the data. This allows the engineer to make informed design decisions that take into account the specific requirements.
The data includes information such as specified hot and cold media, the amount of heat the heat exchanger must transfer, and space and noise constraints. At this stage, we discuss any unique requirements or priority considerations for the project.
These may include:
The fluid or gases the heat exchanger will handle are, of course, a vital consideration.
The unique properties of the fluids involved dictate the most efficient heat exchanger design. It also affects the materials we will need to manufacture the heat exchanger. These ensure a good heat transfer coefficient, plus take into account reactivity both between the fluids, and the fluid and the manufacturing material.
For example, in a shell and tube design, it might be that the two fluids involved risk reactions if they come into contact. In this case, the engineer might use a double tube sheet design to prevent cross-contamination.
The heat exchanger’s material is another important consideration with bespoke designs.
There are a variety of factors that impact the best choice of material, including:
- corrosion resistance
- stress and cracking resistance
- ease of manipulation and manufacture
- melting point
For some heat exchangers, corrosion resistance, for example, will be a more critical consideration than others.
For example, a heat exchanger that handles the vaporising of acid substances might need to be manufactured from tantalum. It has a very high melting point and is almost entirely resistant to acid attacks at temperatures below 150°C.
A heat exchanger that will be in constant contact with seawater, on the other hand, might be best being manufactured with titanium. This is a more abundant element (and therefore cheaper) but has good corrosion resistance. It could withstand sea water for 3 years before showing any signs of corrosion damage.
Learn more about the materials used in heat exchangers.
By using your data to understand the application of the heat exchanger, we can work with you to select the most effective and suitable material for your bespoke product.
An essential element of designing a bespoke heat exchanger is understanding the amount of cooling or heating required. We use our own formulas and thermal model to calculate the most efficient designs based on the temperatures involved.
Creating an efficient design with a good heat transfer coefficient will be a priority for most designs. However, this needs to be managed with other constraints and considerations for the project, such as cost, noise, corrosion resistance etc.
For example, the most efficient material might be the most expensive. However, there will be other suitable materials that provide a slightly less optimised, but still effective, solution at a lower cost.
By understanding all the contributing factors, and your priorities, we can make informed design decisions for each heat exchanger product.
Noise can often impact the design of a bespoke heat exchanger. For example, many coolers will use a fan to circulate air across the finned surface which can be loud.
If staff are working in proximity to the heat exchanger, it’s important that the noise is controlled to protect their hearing and ensure a suitable work environment.
A silencer, for example, could be added to the propeller design. Alternatively, a fan’s velocity could be reduced to lower the vortex generation, reducing the noise.
These can impact on efficiency, so other elements of the design may need to be altered accordingly until the optimum balance is reached between all the considerations.
Other operating conditions that need to be considered in bespoke heat exchanger designs include:
- size constraints
- operating pressures
- ambient conditions such as salt water, dusty environments etc
Each of these aspects could significantly affect the design of the heat exchanger.
Fouling and maintenance
For example, the fluids involved and the ambient conditions can lead to fouling of the heat exchanger. In turn, this leads to cleaning and maintenance requirements.
If we understand these requirements, we can design a heat exchanger that you can easily clean.
Budget is, inevitably, often a significant consideration. For example, it can influence which material is most appropriate to ensure a good heat transfer coefficient without pushing the cost beyond the budget of the project.
Depending on the location and industry in which the heat exchanger will operate, there might be specific design standards to which we must adhere.
We are experienced designing heat exchangers within international standards, such as ASME, as well as country-specific standards and codes.
Read more about heat exchanger standards.
While most considerations for bespoke heat exchangers are handled in the design stages, the manufacturing process itself comes with a range of specific considerations.
There are a huge number of processes and techniques that might be used in the manufacturing of a bespoke heat exchanger.
It will depend on the material and design as to which will be most suitable.
In addition to adhering to design standards, projects might also have specific manufacturing standards that need to be followed.
For example, shell and tube heat exchangers are built to TEMA standards. Heat exchangers for the oil and gas industry are manufactured to API standards.
Read more about heat exchanger standards.
We need to transport the heat exchanger, once manufactured, to the operating site. The logistics of this are extremely varied depending on the location, the conditions, and the size of the heat exchanger.
For example, we might ship a large heat exchanger in multiple shipments and discuss with you the best solution for the final assembly of the product on site.
Other times, we will advise clients on the machinery they will need to unload the heat exchanger shipment and set it up in its position at the site. This could be a mobile crane and associated equipment, for example.
At Sterling TT, we understand that every heat exchanger is different and will have unique challenges it must overcome in order to operate effectively. This is why all our heat exchangers are designed bespoke to your requirements.