Always staying cool
07.11.2016
Refrigerators have to be well insulated in order for their cooling capacity and energy efficiency to meet required levels. This is particularly true for tropical climatic conditions in southern latitudes.
Refrigerators have to be well insulated in order for their cooling capacity and energy efficiency to meet required levels. This is particularly true for tropical climatic conditions in southern latitudes.
- Whirlpool India uses KraussMaffei RimStar technology in manufacturing polyurethane insulating layers in refrigerators
- Mixing and metering systems prove their value with stable production processes and high mixing quality
In India, Whirlpool India - a subsidiary of US-based global conglomerate Whirlpool - is the market leader in manufacturing refrigerators and cooling systems. For producing the critical insulating layer made of foamed polyurethane (PUR) in the housings and doors, the company insists on KraussMaffei's RimStar mixing and metering technology.
Every day, about 6,800 refrigerators leave the Whirlpool plant in Faridabad in North India to be sold throughout India and neighboring countries. The KraussMaffei RimStar machines, five in total, provide perfect insulation of the housings and doors, contributing to the refrigerators' exceptional energy balance. Pentamix systems providing optimum premixing of the pentane component were also part of the order.
Whirlpool is not a new customer for KraussMaffei. The collaboration started back in 2012. The first wet side equipment, a RimStar 80/80, was sent to Brazil and has been successfully producing refrigerators in South America ever since. "The RimStar system in Brazil has impressed us in recent years with its reliability and production consistency," explains Rohit Dhiman, Director Projects at Whirlpool Faridabad. "It was only logical for us to again choose KraussMaffei when making the new investment." Dhiman also praises the technical expertise of their contact persons as well as the good and close cooperation with the team of KraussMaffei and their representation Goodies International: "They have impressed us with their flexibility of timings and deep knowledge of project execution during the whole project planning and final commissioning. In total, a perfect sync with the Whirlpool team on site."
Stable process control and high product quality
The primary strengths of the RimStar systems include stable process control and high product quality. The definitive reason for this is the KraussMaffei mixing head technology. Depending on the application, the five new RimStar systems at Whirlpool are equipped with up to 10 mixing heads. For the polyurethane foaming of the refrigerator housings and doors, linear and transfer mixing heads from KraussMaffei are used in this case. The main characteristic of these transfer mixing heads is laminar and splash-free pouring of the mixture into open and closed molds. They are particularly designed for processing hard-to-mix systems Their other advantages include long service lives and low maintenance costs.
Another outstanding feature of the KraussMaffei RimStar machines is the particularly precise temperature control of the components, which guarantees a constant temperature at all times. In this application, pentane is employed as the blowing agent to avoid using chlorofluorocarbons. The entire equipment configuration was manufactured in accordance with German TÜV specifications, with a successful acceptance carried out onsite by TÜV-Süd.
Pentamix systems feature outstanding premixing performance
Optimum premixing of the pentane component in the production line for refrigerator housings and doors is provided by the fully enclosed Pentamix 40 premix stations from KraussMaffei. The pentane is safely introduced into the polyol component. For this purpose, a 40l high-pressure pump developed in-house is used (on the polyol side), along with a 5l plunger metering pump. High metering accuracy is achieved even at very low feed rates. The proportion is monitored by means of flowmeters for polyol and pentane. The housing is completely suction-cleaned and monitored for leaking material.