| 165 / | HD | HEAT EXCHANGE |
| DIG 51 | DD | HAVING EXPANSION AND CONTRACTION RELIEVING OR ABSORBING MEANS {2} |
| DIG 52 | DD | .~ For cylindrical heat exchanger {6} |
| DIG 67 | | .~.~ Cylindrical heat exchanger rectilinearly slidable relative to its support {1} |
| DIG 68 | DD | .~.~.~> Including fluid seal |