DHP's range of Plate Heat Exchangers includes a wide selection of configurations (Single pass, Multi pass, Single & Multi pass) and capacities, as well as plate and gasket material to literally cover any possible need on board a ship.

Design

The main components of the DHP Plate Heat Exchangers:
The plate pack comprises of a number of heat plates, according to the heat transfer surface required.
Gaskets on the plates ensure that the flow channels are securely sealed from each other.
The gaskets also determine the direction of flow within the exchanger.
The frame enclosing the plate pack is held together with tightening bolts.
Connections for incoming and outgoing fluids are usually in the fixed frame of the heat exchanger.
In the case of multi pass flow, connections have to be in the fixed frame and the movable frames.

Operation

Adjacent plates form flow channels carrying alternately hot and cold fluids throughout the plate pack.
Normally, single pass heat exchangers are used, permitting 100% counterflow of both products.
All port connections are located in the fixed frame plate providing a low maintenance installation.
In cases of low temperature differences, or where these differences are to be fully utilized, multi pass Plate Heat Exchangers become more economical.
Provided the number of passes is the same for both fluids nearly 100% counterflow will be achieved.

Configurations:

SINGLE PASS
As single pass has the counter flow and the nozzle is mounted on the fixed frame, only frame can be moved for maintenance so it is easy for the maintenance and increase or decrease in capacity.

MULTI PASS
If the flow rate is quite less than heat transfer rate and the pollution level is not much, the advantage is that the heat transfer effect can be increased significantly by designing both hot side and cold side to be multi pass but the disadvantage is that the piping of nozzle part in the movable frame should be corrected when it is necessary
to expand the heat exchanger capacity.

SINGLE PASS &MULTI PASS
If the temperature is much different between inlet and outlet and the allowable pressure loss between hot side and cold side is much different, the performance can be enhanced by increasing overall heat transfer coefficient, making one side to be 1 pass and the
other side to be multi pass.

MATERIALS:

For Plates:
Stainless steel- 304, 316, 316L, 317, 316Ti, AVESTA 254 SMO
Special Materials: Hastelloy - B,C, Incoloy, High Grades of Titanium, Titanium, stabilized with Palladium, NLCP (Nickel), Tantalum

For Gaskets:
NITRILE(NBR), HNBR, HYPALON, BUTYL, FPM, FPM-G, EPDM(Ethylene, Propylene Diene, Methylene), SILICONE, NEOPRENE

For Frames:
CARBON STEEL, SUS 304, 316, SUS LINING

MAINTENANCE

Maintenance on DHP Plate Heat Exchangers can be carried out easily.
For inspection and manual cleaning simply release the movable frame to allow the plate pack to be taken apart.
Other forms of cleaning such as back flushing or chemical cleaning can be done keeping the exchanger assembled.

DHP Plate Heat Exchangers save costs, with their high efficiency, low investment, compact installation and simple maintenance.

Key Features

Cost Savings
DHP Plate Heat Exchangers save costs, with their high efficiency, low investment, compact installation and simple
maintenance.

High Heat Transfer Coefficients
DHP Plate Heat Exchangers provide high rates of heat transfer, due to the turbulence inducing shape of the plates.
The special gasket configuration of the plates prevents any mixing of the media being processed. In the port area both fluids are separated by double gaskets. Additional safety is ensured by the leakage gap.

Adhesive-Free Gasket
DHP developed adhesive-free gaskets. The optimum gasket setting in the gasket groove and the fixing of the gaskets by pressed indentations, allow high resistance against pressure and enable a quick and simple gasket replacement.

Flexibility
DHP Plate Heat Exchangers can be adapted to changing process conditions. If process conditions change plates can be added or removed easily. This eliminates the need for costly re-investment.

Low Product Content
This small volume of liquid in the Plate Heat Exchangers is the reason for the low weight of the equipment. It enables a faster start up and shut down of the complete plant, than conventional heat exchangers.

Compact Design
DHP Plate Heat Exchangers are of compact design. For example, 200m2 of heat exchange surface require a Plate
Heat Exchanger of only approx. 3m length, 2m height and 1m width. For a shell and tube heat exchanger to achieve the same duty, about 600m2 of heat exchange surface would be required.

Reliable Gasket Structure
DHP’s new development of ‘Tri-Seal’ gasket system overcomes the limitation of ordinary plate heat exchanger (3 times higher-pressure endurance).