DWK series water cooler

>> Data Sheet (PDF)

Description

DWK series water coolers are designed to supply and cool closed circuit cooling systems, in particular those used with Nd YAG lasers. A number of different coolants can be used, e.g. deionized water, oil, etc. However, this fact must be taken in-to account in the design. Temperature is adjustable, but it may not be less than the cooling water temperature. The water cooler is therefore installed between the consumer and an existing cooling system (refrigerator, cooling water circuit). If no cooling water is available, the water cooler can be supplied together with a refrigerating compression. Depending on the temperature requirement, a number of different control systems are used. The water
cooler can therefore be used for temperature stabilization.

Design

The water cooler has its own water tank, which contains the coolant, a heat exchanger made of stainless steel, a feed
pump and a temperature control device. The closed circuit therefore consists of tank – pump -consumer – tank.

Connections of the DWK series

If deionized water is used, an ion exchanger and a particulate filter can be installed in the circuit (option). The rating of the heat exchanger, and ultimately the rating of the water cooler, must of course be known because they depend on a number of parameters such as the temperature difference between the cooling circuit and the external cooling water, and the water volume. The heat exchanger is then calculated according to these values. Moreover, the design of the heat exchangers has a major impact on the control action.

Mechanical design

The system is completely mounted on a base plate and can be supplied as a complete panelled unit in a 19” rackmount (fitted with rollers on request). The system is fully wired and fitted with internal piping. All the switches, fault displays, level gauges and the control unit, etc. are mounted on the front panel. The voluminous tank in relation to total system size is made of plastic. In the optional version supplied for operation with deionized water, the particulate filter is mounted in the feed line and the ion exchanger in the bypass. The centrifugal pump is completely made of stainless steel and plastic, and is therefore corrosionfree. The heat exchanger is designed as a plate exchanger. It can also be made of stainless steel (material 1.4401) in a very spacesaving design. It is fully welded. This is why no ions or any other bodies can be released from the filler metal. The standard piping consists of plastic hoses and brass nozzles. In the deionized water version, all parts in contact with the deionized water are made of rigid PVC or PA. Lines and fittings made of PVDF can also be supplied. The options include a wide variety of safety devices such as flow controllers, pressure controllers, conductance monitors, monitors and displays for water quantity and in- stantaneous cooling capacity, through to ports for connection to a central process controller or a computer.

Temperature control

Maintaining the desired temperature depends on a number of factors. The water cooler is supplied as standard with two different temperature controllers. The standard is a temperature constancy of +_ 1 K. For a temperature constancy of +_ 0.5 K, a different control system is installed. If a higher temperature constancy is required, our constant temperature controller is used. The water temperature is digitally displayed on the controller. A heater can also be installed if temperature equalization
is required instead of cooling.

>> For more technical details, diagrams, etc. see the data sheet (PDF)