Allweiler delivers chemical pumps

In October 2010, Allweiler AG fulfilled a large order for centrifugal pumps in China. The PET, glycol, and thermal oil pumps are part of expanded polyester production in Wujiang. A large number of Allweiler pumps have been in operation at the site since 2003. The order was for eight pumps for PET production, 140 glycol pumps, and 20 thermal oil pumps for the plant's primary and secondary loops. The pumps delivered to Wujiang will be used to expand a polyester production plant.

According to Stefan Kleinmann, Vice-President of the Industry business segment and member of the Allweiler AG executive board: "Allweiler AG won this contract because the operator of the plant has been using our pumps with great success since 2003. The long-term and effective support provided by our subsidiary in Shanghai was another reason."

The pumped liquid can reach temperatures as high as 280°C during production of synthetic yarns. For this reason, the pumps are manufactured from 1.4581-grade stainless steel, a highly heat-resistant material. The special metal bellows-type seals are also designed to handle these high temperatures. The CNH-B series pumps are equipped with supplemental heating because liquid polyester begins to solidify below 250°C. Capacity is 400m³ per hour at a pressure of approximately 14bar; drive power is 180kW.

Allweiler's largest chemical-standard pumps from the CNH-B series in size 200-500 are used to move thermal oil in the primary loop. This series reaches a capacity of 1200 m³ per hour at a maximum pressure of 25bar and a maximum delivery head of 147m. Liquid temperature can be as high as 350° C. Pumps of types NTT and NTWH are used in the secondary loop, depending on the liquid properties. In this application, the "Therminol" heat transfer oil reaches temperatures of 330° C and higher.