seen in fig2 the pump 10 and the motor 12 are generally conventional in construction and as such the pump 10 is illustrated as a volute type double suction pump having an intake or suction opening 18 and a discharge opening 20 while the motor 12 may be of any suitable construction or type a mechanical seal arrangement which is generally identified as 22 is disposed around the pump shaft to substantially contain the high pressure fluid in the pump the mechanical seal assembly 22 forms no part of this invention and is conventional in construction it is shown as of multiple elements and assemblies for purposes of illustration between the pump 10 and the mechanical seal assembly 22 and surrounding the shaft or drive line assembly 16 is a heat exchanger generally identified as 24 for purposes of further description attention is directed to fig3 to 6 inclusive which illustrate in a simplified version the heat exchanger 24 of this invention parts 52 and 54 are omitted in fig4 for sake of clarity they are illustrated in fig3 the heat exchanger 24 comprises a first cup like cylindrical member 25 having a first and inner axial cylindrical portion 26 having.