HRS DTA Series: Food-grade double tube heat exchanger.
The DTA type heat exchanger is a double tube heat exchanger (tube within a tube), similar to the DTI type heat exchanger,
but with a design that is suited for food industry applications. The inner tube is corrugated for increased heat transfer.
The product flows through the inner tube and the service fluid through the annulus between the inner and outer tube. Because
of its geometry, the DTA heat exchanger is a true counter current heat exchanger.
Manufactured from AISI 304 / 316L stainless steel the HRS DTA Series is a tube in tube heat exchanger with the inner tube
designed to carry the process media whilst the outer tube carries the service media. Supplied as standard in lengths of
3 and 6 metres with process tube diameters ranging from 1 to 4.5 the HRS DTA Series is capable of handling large particulates
of up to 50 mm.
Three versions of corrugated tubes are available for this unit including hard corrugation designed to generate maximum turbulence
for an optimum pressure drop, and soft corrugation designed to increase wall velocity with the minimum of pressure drop.
Corrugated tube-in-tube heat exchangers have many benefits and advantages over comparable smooth tube versions:
- Heat transfer coefficients of up to 2½ times higher can be generated.
- There is no significant obstruction to the flow area of the tube so that they can be used for fluids with a high solid or
fibre content with no fear of blockage.
- Increasing the tube side heat transfer coefficient brings the temperature of the tube wall closer to the temperature of
the bulk fluid, minimising fouling.
- Due to the higher coefficients achieved, heat exchanger size can be reduced by as much as half.
- In-situ cleaning is improved because of the increased turbulence generated by the corrugated tube, which in lower viscosity
fluids minimises the tendency for deposition fouling to occur. If fouling does occur the deposits are normally very easy
to remove since corrugation leads to an uneven film thickness.
Applications.
- Fluids containing fibers or other solids.
- Low to high viscosity fluids.
- Food products.
- Products with aseptic fruit particulates, tomato dices, etc.
Materials.
- Shell side: AISI 304 stainless steel.
- Tube side: AISI 316L stainless steel.
Connections.
- Shell side: DIN flange.
- Tube side: Clamp.
Finishing.
- Shell side: Externally polished.
- Tube side: Roughness < 0,8 microns.
Design conditions.
- Shell side: 10 barg / 150 °C.
- Tube side: 10 barg / 150 °C.
An expansion bellow is fitted in the outer shell for absorbing the differential expansion between the shell and the inner
tube.
For large duties, multiple units can be interconnected and mounted in a frame.
| Model | Length (m) | Area (m2) | Shell side connection | Tube side connection | Max flow shellside (m3/hr) | Max flow tubeside (m3/hr) | Volume shellside (l) | Volume tubeside (l) |
|---|
| DTA 51/25 | 3,0 - 6,0 | 0,4 | DN40 | 1" | 13 | 4 | 8,2 | 2,5 |
| DTA 64/38 | 3,0 - 6,0 | 0,6 | DN40 | 1,5" | 17 | 10 | 10,3 | 5,7 |
| DTA 76/51 | 3,0 - 6,0 | 0,9 | DN40 | 2" | 18 | 18 | 14,1 | 11,0 |
| DTA 104/64 | 3,0 - 6,0 | 1,1 | DN65 | 2,5" | 43 | 29 | 29,7 | 16,9 |
| DTA 104/76 | 3,0 - 6,0 | 1,3 | DN65 | 3" | 33 | 41 | 21,5 | 24,8 |
| DTA 129/104 | 3,0 - 6,0 | 1,8 | DN80 | 4" | 37 | 77 | 26,0 | 46,4 |
The surface area and volumes shown are for 6,0 meter lengths models.