The innovative valve station concept ICF for industrial refrigeration units

Saturday, June 30, 2012

"Time is money" is a watchword that applies more than ever to today’s western world.The ICF valve station is a compact, preinstalled ready-to-connect solution that is ready for use with just two welds, enabling users to dispense with up to ten additional welding operations. And with just two welding operations for each ICF valve station they offer the same functionality as a whole series of conventional industrial valves put together. You can use ICF valve stations to replace a number of mechanical, electromechanical and electronic valves mounted in series, and if you use TIG welding you don't even need to remove the function modules before welding.

A number of different functions – Only one valve station

Up to six functions can be integrated into a single valve station. There are housings for up to four main functions (M1, M2, M3 and M4) connected in series, designated ICF 20‑4 or ICF 40‑4 for higher capacities. For more complex tasks there are also ICF 20/40‑6 valve stations available that are able to accommodate up to six main functions. The following valve function modules are available for the "M" main function slots in a valve station: shut-off, manual regulating, filter, solenoid, electronic expansion, manual spindle for solenoid, check function, shut-off/check function and motorised, plus a dummy cover and an external weld connection spigot. 

The lateral "P" connections can also be used for a sight glass, pressure or temperature sensors, a manometer or an output line. There are thus an almost infinite number of possible combinations and functions. One basic rule for setting up an ICF valve station is that there must always be either a shut-off valve or a combination shut-off/no-return valve on the inlet and the outlet of the ICF. This greatly simplifies servicing, because it enables the unit to be isolated whenever repairs are made to the valve station. 

The flow-optimized construction and the possibility of using both sides for valve seats makes it possible to rapidly evacuate the valve station, because its internal volume has been kept extremely small to speed up servicing operations. Moreover, the service technician will find all the controls and shut-off valves in the same place. In a large-scale installation with many ICF stations, the time saved by these measures plus the reduced refrigerant loss rapidly amount to a considerable saving.

 

Installation time – Only a fraction of that for traditional solutions

With ICF valve stations you not only save on service operations but also on the initial installation. Up to ten fewer welds and ten fewer X‑ray inspections for a single valve station . With only two weld seams for each ICF you can implement the same range of functions as for a whole string of high-performance refrigeration valves welded in series, and because the ICF is supplied as a fully assembled unit that has undergone function and pressure testing at the factory, it is always 100% tight. In addition, provided you use the TIG welding process which exposes the unit to less heat, you don't even need to remove the function modules before welding. All of this amounts to a considerable saving in installation time.

 

Choice of valves for flooded evaporators

The ICF valve station is designed for a maximum operating pressure of up to 52 bar with the refrigeration medium at a temperature of ‑60°C to +120°C. This means that the ICF station can be used for any of the usual refrigerants, NH3, CO2 plus other high-pressure refrigerants that may be used in the future. This high-pressure suitability makes the ICF valve concept extremely versatile and usable for almost any application, so you do not need to continually bear this in mind when choosing a suitable refrigerant. Moreover, instead of being confronted with up to six different components as for conventional valves, with the ICF valve station you have just one device and one order number. This makes the task of choosing a suitable valve station extremely straightforward.

For example, suppose we want to choose a valve combination for a flooded evaporator: The system should be regulated in on/off mode using the thermostat and the evaporator should be defrosted with hot gas. Pipe connections should have a nominal diameter of 25mm / 1" and be carried out as DIN weld spigots. There should also be four lateral ports ("P") for external connections. The ICF 20‑6‑3 with order number 027L3020 fulfils all these requirements. It comes with the following function modules: First a shut-off valve, then a filter to catch welding beads and large particles of dirt, then a solenoid valve module for opening and closing the valve station, then a check valve, to prevent anything flowing back from the flooded evaporator (even when it is being defrosted with hot gas), then a manual control valve for throttling the evaporator and finally another shut-off valve so that the valve station can be shut down for servicing operations.

On the same evaporator we will also need a solenoid valve feed module for hot-gas defrosting. Now suppose that we have to connect to pipes of nominal diameter 32mm / 1" via DIN 2448 weld spigots, with two lateral "P" connections also required. The ICF 20‑4‑9 with order number 027L3068 is the right choice here. There are shut-off valves on either side and a solenoid valve module with an upstream filter; as the "4" in its designation implies, the ICF 20‑4‑9 is equipped with four main modules on M1 to M4. In this application, one of the lateral  connections can be used to supply the external high pressure for the GPLX solenoid valve in the pump return line. With pump return lines it is always necessary to be very careful about pressure drops, so GPLX valves are particularly suitable here because they have no minimum pressure drop requirement.

 

Example for dry expansion

Naturally, even ammonia-based systems are not always implemented as flooded systems. For example, suppose we have to choose a combination of valves for liquid injection and a motorised expansion valve for an evaporator with dry expansion and electrical defrosting. The 20mm / ¾" nominal diameter pipes should be implemented as DIN 2448 weld spigots. The system will also need lateral connections for a sight glass and a drainage connection or manometer. The four-module valve station ICF 20‑4‑14A with order number 027L3095 is the ideal choice for this application. It has two shut-off valves at entry and exit and comes equipped with a motorised expansion valve protected by a filter module. This arrangement makes the motorised valve as easy-to-service as possible and greatly reduces downtime. Such a module can be controlled using an EKC 315 regulator. With pressure and temperature sensors at the outlet from the evaporator, the EKC always finds the optimum superheating value and regulates the motorised valve in the ICF station as appropriate. 

Possible application examples are legion and could be continued almost without limit.

 

Conclusion

ICF valve stations are designed for practically all the functions required by industrial refrigeration applications. They are equally suitable for high and low temperature media and for high and low pressures. They can be used both for flooded evaporators and for dry expansion. Even hot-gas lines are no problem. Their universal suitability, unique service orientation and the massive reduction in the number of welds required for installation makes the ICF valve station concept the solution for modern industrial refrigeration plants.