Comparative characteristics of seals for heat exchangers OPEX and other manufacturers
There are several manufacturers on the market. Some suppliers use seals and plates from German, Turkish and other manufacturers. The OPEKS company traditionally uses Swedish seals and plates from one of the world's largest manufacturers of heat exchange equipment TRANTER as part of THERMAKS PTA (GX, GC, GL) heat exchangers, but often the buyer pays attention only to the cost of heat exchangers, not paying due attention to important operational and technical specifications. In pursuit of a low price, many manufacturers of plates and seals have taken the path of reducing material consumption as the main component of the cost of the heat exchanger. Let's try to describe below what important parameters you should pay attention to when ordering heat exchange equipment.
The heat exchanger seal or gasket is an important structural element of the gasketed plate heat exchanger . The seal allows you to create a sealed channel between the two plates, through which the coolant moves. Also, heat exchangers equipped with high-quality seals can work for decades, in some cases, without any maintenance. Good quality seals can be reused after the heat exchanger has been serviced (cleaning from contamination).
The following basic requirements are imposed on seals:
- Ability to maintain elasticity for a long time at design temperatures and environments.
- Sufficient mechanical strength to allow the same seals to be used when disassembling and servicing the heat exchanger.
- Maximum possible service life before replacement.
Comparison of basic geometric parameters of seals
for plate heat exchangers
1. Width of the seal.
The difference in width between TRANTER seals in THERMAKS heat exchangers from OPEKS and other manufacturers can be 2 times or more.
2. The thickness of the seal and its relation to the pressing depth of the plate.
The difference in thickness between TRANTER seals in THERMAKS heat exchangers from OPEKS and other manufacturers can also be 2 times or more.
1. Since each seal is subject to thermal and mechanical stresses, the thinner and narrower sealing material on the plates decreases the elasticity in the compressed state much faster and ages faster, losing its sealing properties. As a result, thin and narrow seals fail faster, the heat exchanger can lose its tightness, leak, more frequent replacement of seals is required.
2. The thickness of the seals is also directly related to the depth of pressing the corrugation in the heat exchanger plates. The shallower the depth of the corrugation, the thinner the seals are made by manufacturers. The depth of pressing out the corrugation in plates of other manufacturers is sometimes 1.5 ... 2 times less than in Tranter plates, which OPEKS uses as part of THERMAKS heat exchangers.
Therefore, for thin seals, plates of small pressing depth are used, this leads to a decrease in the flow area of the channel through which the coolant moves. The smaller the flow area, the smaller the size of contaminants can freely pass through the cross-section of the channel of the plate heat exchanger, the faster it can become clogged and, accordingly, require cleaning and servicing to maintain its characteristics.
It is important to consider the heat exchanger not only in terms of the initial investment, but also in assessing what its operation will result in over time. So, for example, if for every 4-6 years you have to pay the cost of another heat exchanger, purchasing spare parts, performing repairs, cleaning and having problems with emergency stops, then you need to think about whether it is worth paying twice, and sometimes three times, paying attention only at the initial cost of heat exchange equipment, forgetting about the technical side and quality of the heat exchangers purchased.
In the photo, the OPEKS RTA ( GX ) -18 heat exchanger (burgundy) at the first service 15 years after the date of manufacture: