| 摘要 |
<p>In a plant comprising a pump unit for circulating heated liquid within the plant, said pump unit comprising a liquid pump (1,2,3,5) driven by an electric motor (4,6,7), the operating economy is improved by cooling the electric motor by circulating a part-flow of the heated liquid circulated by the liquid pump in a cooling jacket (8) provided in the electric motor (4,6,7). A further improvement is achieved by thermally insulating (10) the electric motor (4,6,7) and the liquid pump (1,2,3,5) from the surroundings, so that the heat losses from the electrical components are utilized for heating the liquid being circulated. <IMAGE></p> |
