Smooth testing of refrigeration units thanks to extremely dry air at high pressure

July 11, 2019

A Spanish company specializing in the mechanical assembly of industrial installations was set to deliver a refrigeration system to a slaughterhouse. Prior to commissioning, however, regulations require refrigeration installations to be tested with 18 bar pressure, which is more than the maximum pressure most compressors provide.

Optimizing efficiency

Before a refrigerant can be added to an installation, the seal of the equipment has to be tested to make sure there are no leaks. As cooling installations operate at -30 to -35°C, the test requires the use of a fluid that does not contaminate the cooling system with water or any other substance that freezes at such temperatures. When the installations are running, a mixture of water and refrigerant can result in internal corrosion, which can badly damage the installation. To avoid this scenario, high-pressure nitrogen bottles are generally used to perform these tests. However, working with nitrogen bottles is expensive and laborious as they require permanent drains, connection and disconnection. Moreover, when you run out of high-pressure nitrogen gas bottles, new delivery and transport need to be organized, resulting in additional administrative hassles and a higher risk of delays for the customer. To boost cost efficiency for the customer, we introduced oil-free dry compressed air as an alternative to nitrogen bottles. Our extremely dry air with a dew point of -50 °C at high pressure is perfectly suited to test such equipment without the risk of frozen residual humidity.

Strict regulations and limited time

Although we quickly found a perfect alternative to nitrogen gas bottles, the project still had some challenges in store for us. First, the slaughterhouse was located in Spain and all equipment therefore needed to comply with Spanish regulations requiring cooling installations to be tested with 18 bar pressure, substantially higher than the maximum of 10 bar most compressors can reach. To solve this problem, we introduced a DXT 85 booster that was able to amplify the pressure of the compressor to 20 bar.

Second, the cooling installations needed to be operational as soon as possible. As building up to 18 bar pressure is time-consuming, we needed to find a solution that could speed up the process and limit the loss of valuable time. By using a stationary oil-free compressor ZT 90 VSD FF, desiccant air dryer CD 400, and booster DXT 85, we were able to increase the pressure relatively quickly and to complete the leak tightness tests in only 2 weeks’ time.

As a result of our quick coordination, the client was able to get the cooling systems up and running without losing too much time to mandatory testing.

Both the customer and our team were satisfied with the project. Thanks to our previous experience with customers in the cooling industry, we really understood what this project needed. In addition, we were able to offer added value by pointing out potential difficulties that could occur during the installation and test process.

Javier Acuna , Sales engineer at Atlas Copco Rental Spain

For more information please contact:

Great ideas accelerate innovation. At Atlas Copco we have been turning industrial ideas into business-critical benefits since 1873. By listening to our customers and knowing their needs, we deliver value and innovate with the future in mind. Atlas Copco is based in Stockholm, Sweden with customers in more than 180 countries and about 37 000 employees. Revenues of BSEK 95/ 9 BEUR in 2018. Learn more at www.atlascopcogroup.com. Great ideas reinforce sustainable development. At Atlas Copco Specialty Rental we team up with our customers to set up state-of-the-art temporary air, power, flow, steam and nitrogen solutions. Our passionate experts have extended application as well as equipment knowledge. We understand our customers' needs and can provide a total solution for any industry, no matter if it is for emergencies or planned projects. We are a division of the Power Technique business area, headquartered in Boom, Belgium and offer specialty rental solutions under several brands around the globe.