The growing size of transcritical CO2 refrigeration systems, including those installed in cold-storage and food processing plants, led German manufacturer Sanha to expand its RefHP 29000 series of high-pressure copper-iron fittings this year to include a 2-5/8in (6.66cm) model.
“[CO2] installations are getting bigger and bigger and the demand for more cooling capacity is increasing, which automatically led to the demand for the specific size 2-5/8in,” said Mathias Van den Broeck, Business Development Manager at Sanha. He added that “with these installations there is otherwise a need for two supply lines of 2-1/8in. With the new products in the range, this cooling capacity can be met with one line.”
The 29000 range, which can accommodate up to 130bar, and temperatures from -196°C to 150°C (-321°F to 302°F), can be used in CO2 commercial and industrial air conditioning and refrigeration systems.
The fittings are compatible with all copper-iron tube types available on the market, including those from Halcor, Wieland and HME.
“Previously [our] portfolio was expanded with the size 2-1/8in (5.4cm) at the request of manufacturers of refrigeration units,” said “Originally, we thought this was a niche market, but the size appears to be very popular.”
Soldering vs. welding
The RefHP series consists of soldering fittings made of copper-iron, Van den Broeck explained. “In the alloy, iron was added to the copper to make the material harder and more robust, allowing higher pressures to be achieved than standard copper.”
The new fittings are not technically easy to make due to the “enormous” wall thickness, according to Valérie Matthys, Van den Broeck’s product management colleague..
“Thanks to our own mechanical engineering we are able to provide the necessary power in the machines,” she added, praising Sanha’s product development team for making the company able to respond quickly to this rising market demand.
Other companies are not yet able to offer this product, according to Matthys, and offer brass fittings instead. Soldering brass is slower than doing so with a copper-iron alloy, as it needs brass be heated more slowly. This saves customers using RefHP fittings 25% of their time, she explained. “Brass must also be soldered with a higher silver content than copper iron, making it more expensive.”
The new soldered fittings are also advantageous when compared to TIG welding, especially when looking at time saving. “Soldering is much easier than TIG welding and is 2.5 times faster,” Van den Broeck said, adding that due to the speed, labor costs are lower, and with soldering technicians won’t have to go through annual TIG welding training, something that is both “expensive” and “time-consuming.”