Keeping cool in the Algerian heat

The heat exchangers and pressure vessel solutions manufacturer ASTRA Refrigeranti needed tough and reliable axial fan motors for mobile air coolers used for oil extraction work in Algeria. The answer was a fully customised solution from Hoyer – delivered in just four weeks.

Extracting crude oil from the Algerian underground is a hot and dirty job. So, when the Italian heat exchangers and HVAC specialist ASTRA Refrigeranti got an order for mobile air coolers for the oil industry in Algeria they knew that they needed parts that could withstand the demanding conditions, such as coarse desert sand, high humidity and changing temperatures. And due to the presence of flammable gasses from the oil extraction, all equipment naturally needed to be ATEX-certified.

Fully customized solution

ASTRA turned to Hoyer to supply the motors for a total of 15 axial fans in the cooling towers. Even though it was a challenging request from a new customer Hoyer’s HVAC team was ready to take on the challenge from the Italian client.

“We needed to deliver a 100 percent customised solution on a tight deadline. Fortunately, we have extensive experience from similar projects, both with axial fans for cooling towers as well as the ATEX requirements”, says Adam Slupinski, HVAC Segment Manager at Hoyer Motors.

Keeping out dust and moisture

The presence of dust and humidity presented a special challenge. With shifting temperatures, there was a significant risk of condensation forming within the motors. To prevent this, Hoyer added heating elements to the motors and applied winding topicalization, a special coating to protect the windings against corrosion and potential short-circuiting. Furthermore, the V1 mounting position of the motors also called for extra care.

“Because the motors are mounted vertically on the axial fan, they need a special extra sealing to prevent dust and moisture from being pulled by the motor fan through the rotor and into the motor casing. We added special seal rings to ensure that the motors were fully protected, even in very dusty or humid conditions”, explains Adam Slupinski.

Reliability and speed

During the design of the solution Hoyer worked closely with the project team from ASTRA, making sure to keep the process moving as swiftly as possible. Once the design was in place, Hoyer also provided complete documentation in French, including motor name plates, datasheets and instruction manuals.

“Working with Hoyer Motors, we experienced high reliability and an excellent delivery time. Their team was great in suggesting specific solutions and made it possible to complete the project in just four weeks, from order to delivery in Italy”, says Andrea Meloni, Sales Engineer, Astra Refrigeranti.

The customized solution

  • Hoyer delivered a total of 15 pcs 18,5 kW axial fan motors for 5 mobile Air Coolers
  • The motors were ATEX-certified Zone II 3G Ex nA IIC T3
  • Custom solutions included:
    – Designed for increased +55 dgr. C ambient temperature.
    – Space heaters and winding tropicalization due to high humidity
    – IP66 auxiliary terminal box
    – Special seal rings to protect the motor from dust, moisture and high temperatures
    – Bearings for high temperature duty
    – French documentation package (motor name plates, datasheets, maintenance manual and certificates)

Facts about Astra Refrigeranti

  • Established in 1948
  • Manufacturer of air coolers, gas coolers, heat exchangers, distillation columns, reactors and steam surface condensers
  • Experts in customised solutions
  • Part of the global Baglioni Group since 2016
  • Specialised in solutions for the Oil & Gas industries