| 165 / | HD | HEAT EXCHANGE |
| DIG 135 | DD | MOVABLE HEAT EXCHANGER {4} |
| DIG 139 | DD | .~ Fully rotatable {5} |
| DIG 140 | DD | .~.~ Rotating heat exchanger having rotating flow confining structures or chambers for two separate heat exchange fluids {2} |
| DIG 141 | DD | .~.~.~ Concentric flow confining structures or chambers {1} |
| DIG 142 | | .~.~.~.~ Jacketed shell |