Vahterus Heat Exchanger

[samiam]

I don't know if this is new technology:

Has anybody used the Vahterus Heat Exchanger (or equivalent) - i.e. Plate & Shell heat exchanger. What were the advantages, disadvantages ...

Note it is a combination between a PHE and a Shell & Tube heat echanger.

[bruceboldy]

Samiam

The plate and shell heat exchanger looks to be a great product. It does have a few shortcomings though.
I was with a company who built a version of this unit. The amount of capacity to physical size it can produce is truly incredible. You know they first weld the plates sections together then compress them together for the completed plate area assembly to go into the shell.
The problem we had when using it as a chiller -- refig on one side and water / brine on the other was a high failure rate on the edge welds. We did not believe they were all just manufacturing flaws but perhaps some cases of excessive pressure due to flash gas in the limited internal areas..

We were though, buying the plate section at the time.

The unit can operate with refrig or fluid on either side, thus you can have a very high pressure system. and can be easily cleanable if need be. The shell can be designed for the pressures needed. The plates have a very high rating if the edge weld holds up.

I think they will really get going in the future, they are compact, the plates are stainless steel the pressures and flows can be on either -the shell or the plate side thus they can adapt to many applications with refrigerant or outherwise.

if you need more data send me a email and i can give you some good data on applications.


best to you
Bruce
Bruce

[Sturt]

Hi Samiam

I have had some experience with a drinks processing plant using Ammonia/Glycol with a duty of 2.5kW.

The efficiency is good for size but reliability of welds is questionable. weld failures on two occasions with less than pleasant results with the Ammonia plant.

As a result of this the primary contractor will work with PHE for now...

Like many things the more the technology is used, developed and selected correctly the more popular and reliable it will become.

Sturt.

[alphi]

Hi Samian,

we commonly used this type of heat exchanger as oil cooler for ammonia systen in a thermosiphon. Oil flows inside the plates and ammonia in the shell side.
To start with, kindly note the nameplate data of the heat echanger if it complies the operating pressures/temperature on the designed duty.

In my own opinion, the disadvantage for this unit is you cannot increase the capacity by adding plates unlike semi-weld type that is upgradeable.

alphi

[N.Ingledew]

Hi
These are good when they don't fail, the problem is the welds are all done by hand and i have known a few to fail, my old company used them for CO2 on one side and ammonia on the other at very high pressures. there is another company in Germany that uses automated welding of the plates but we never used them. I can't remeber why, when selecting be sure to specify pressures on both sides of the plates as the manufacturing process takes this intp account when pre-stressing the units. I Think the manufacturers will get on top of the welding as they are getting a lot of bad press.