WTK Heat Exchangers

WTK range of products include shell & tube evaporators dry-expansion and flooded type, shell & tube condensers also for maritime application, brazed plates, oil separators, liquid receivers, oil coolers, economizers, desuperheaters and are suitable for applications related to the air conditioning, commercial and industrial refrigeration, process, heat pumps, heat recovery and others. It consists of heat exchangers shell & tube type suitable for capacities from about 20 kW to 2500 kW, brazed plates for capacities from about 5 kW to 400 kW, oil separators single and double stage for suction volumes beyond 2500 m3/h, horizontal and vertical liquid receivers from about 30 litres to 1000 litres and over.

Shell and Tube Evaporators – U Tubes

MODELS (dry-expansion) SCE – DCE – TCE – QCE – SBE – DBE – TBE – QBE – SFE – DFE – TFE – QFE All the evaporator models have the tube bundle composed of a series of pre-shaped “U” tubes enabling a free expansion of the bundle independently from the shell; in addition, such bundle is removable (from model SCE – DCE 63 included). There is the possibility to change the position of the water connections (vertical, right or left). The baffles are positioned to enable a nominal velocity of the fluid compatible with the pressure drop which may occur and to reduce to the least possible any by-pass of fluid. Besides such models can be assembled with different distance between the baffles in order to grant high efficiency even when the flow rate is low, particularly with anti-freezing solutions.
The options available are welded feet, water connections flanged type, thermal insulation fireproof with thickness from 10mm to 40mm, adhesive electric heaters, tubes of stainless steel or Cu/Ni-90/10. Series _CE and _BE can operate with various types of refrigerant and are also available for high pressure (45 bar), while the series _FE is designed and optimized to work with R134a and HFO and it is as well available for high pressure (30 bar).

Evaporators with Water Tanks

MODELS TW
The buffer water tanks with integrated evaporator offer an interesting solution to the applications where it is necessary to have always available some cool water ready to use. Matching a tank with the function of water storage with a shell & tube evaporator “U-tube” type purpose modified for the scope, the above result can be achieved. The water storage is possible either on the entering or leaving water. Each tank has been designed to be matched with evaporators of different cooling capacities, so for the same water storage volume different cooling capacities are available. The range includes models with storage volume from about 190 litres to 3000 litres, that can work with evaporators whose duty goes from about 20 kW to 1600 kW.
The options available are special welded supports on top of the tank for the fixing of other components and the thermal insulation.
Test, quality, working limits are the ones of the installed evaporators (attention: design pressure water side = 6 bar).

Shell and Tube Evaporators – Straight Tube

MODELS (dry-expansion) SPE – DPE – TPE
The evaporators of the series -PE are named “single pass” or in perfect counter-current with reduced footprint against the traditional evaporator’s “U” tubes. They are purpose designed for applications with refrigerant R134a and HFO and can grant very high performance of the chiller thanks to half-reduced approach between the evaporation temperature and the outlet of the cold fluid with respect to what is obtainable with heat exchangers made with “U” tubes. The refrigerant volumes at same performance and cooling capacity are rather lower due to the good efficiency of the heat exchange. There is the possibility to change the position of the water connections (vertical, right or left). The baffles are positioned to enable a nominal velocity of the fluid compatible with the pressure drop which may occur and to reduce to the least possible any by-pass of fluid. Besides such models can be assembled with different distance between the baffles in order to grant high efficiency even when the flow rate is low, particularly with anti-freezing solutions.
The options available are welded feet, water connections flanged type, thermal insulation fireproof with thickness from 10mm to 40mm, adhesive electric heaters.

Flooded Evaporators

MODELS (flooded) FME – FWE
The flooded evaporators offer energy efficiency and heat exchange performance never achieved with other models, following in this way the market current needs and the ones of all the manufacturers of chillers. The flooded evaporator has been designed mainly for air conditioning using non-azeotropic refrigerants; thanks to some research and development of special finned tubes, our various models can cover a wide range of cooling duties with minimum temperature approaches, even 1-1,5 K between the evaporation temperature and the fluid outlet to be cooled down. Thus, these models can give the highest levels of C.O.P. and energy efficiency at each operating condition. Our flooded evaporators can be installed with any type of compressor, both oil free and screw type; in case of compressors using oils rather viscous not mixable with the refrigerant we can advise to install our secondary oil separators model RS. All the evaporators’ series FME can be manufactured with variable lengths upon specific applications. The relation between the footprint and the working conditions results in this way always the best possible achievement. All the evaporators’ series FWE instead, have modular fixed lengths but are made with the last generation of high efficiency exchanger tubes, granting therefore the utmost performance.
The options available are welded feet, thermal insulation fireproof with thickness from 10mm to 40mm, sight glass.

Shell and Tube Condensers

MODELS CF – CF /M
The shell & tube condensers have been designed exploiting the best technical solutions to be suitable for all the air conditioning and refrigeration applications. The range of products at nominal conditions have heat rejection capacities from 10 kW to 2500 kW with only two shell lengths (anyway, if required, it is possible to manufacture also with increase or reduction of such lengths). The bundle is assembled with special high performance copper tubes, externally finned, and internally striped for a low fouling factor. Thanks to the combination of these two features, enhancement of the refrigerant and water side, the condensers have a smaller footprint and less weight than the traditional constructions for the same duty. All the condensers can work in tower water and city water configuration and, if made of different materials, they are suitable for sea water application. The refrigerants to be used are all the CFC, HFC, HCFC, HFO. Upon the water flow rate, the configurations 2 pass, 4 pass, 8 pass on the water side are available. The available options are welded feet, sight glass, support for compressor, flanged connections. The series CF is available in special version for design pressure equal to 42bar on the refrigerant side and 16bar on the water side.

Oil Separators

MODELS RS -ECO
The purpose of the application of the oil separators, installed after the screw compressors, is the one to separate the lubricant oil from the refrigerant fluid reducing the quantity of oil in circulation in the plant thus improving the overall efficiency. The refrigerants are all the HCFC, HFC, HFO, NH3 and others as long as compatible with the manufacturing materials. Our vertical oil separators have a separation capacity, for screw compressors, suitable for refrigerant flows (of primary brands) included between 120 and 2250 m3/h.
The separator consists of two sections: the higher one which is adequately designed to obtain a high degree of separation of the oil from the refrigerant gas and a lower one where the separated oil drops and accumulates to be later sent back to the compressor (except ECO version). Our range offers solutions with and without receiver and with single stage (cyclonic) or double stage (cyclonic and filtering).
All the oil separators are submitted to a pressure test to check the general tightness and the quality of the welding’s.

Liquid Receiver

MODELS HLR
The liquid receiver’s series HLR are the ones manufactured in horizontal execution.
The standard range includes models with volumes from about 30 litres to 1000 litres, but special versions are also feasible with larger size.
The options available are welded feet, sight glasses, extra sockets.

Brazed Plates

MODELS P4 – P7 – NP7 – P12 – P15 – P16 – P30
All the brazed plates WTK are manufactured with stainless steel AISI304 plates and brazed with pure copper (Cu 99,9%). The assembly of the heat exchanger is done overlapping the stainless-steel plates rotated of 180° with an intermediate plate-shaped copper foil. This way the chambers for the circulation of the fluids are created.
The available options are fixing stud bolts, feet and lifting lugs, Victaulic or flanged connections, extra sockets for sensors, thermal insulation thickness 10mm, connections on the back side, high pressure version (45 bar except P4).
All models BPHE produced by WTK are certified PED-CE (Dir. 2014/68/UE) and have successfully passed the necessary pressure and vacuum tests.
The quality checks are in compliance with the internal quality system manual UNI EN ISO 9001 and specifically all the brazed plates are submitted to pressure tests carried out by automatized systems.