Tube bundle-type heat exchanger, tube base, and method for sealing same

A shell-and-tube heat exchanger, comprising:

• a tube base including a first tube base plate with a core and plastics sheathing surrounding the core,
• a second tube base plate made of a temperature-resistant material, wherein the temperature-resistant material has no substantial flow behaviour for temperatures up to at least 200° C. and no substantial thermal expansion for temperatures between −50° C. and 200° C., and
• a third tube base plate with a core and plastics sheathing surrounding the core,
• wherein the first, second and third tube base plates are stacked to form a stack, wherein the second tube base plate is arranged as an intermediate plate between the first and the third tube base plate, so that a first surface of the second tube base plate is directed towards the first tube base plate and an opposite second surface of the second tube base plate is directed towards the third tube base plate, and wherein the stack comprises at least one through-opening for receiving a respective tube of the shell-and-tube heat exchanger, and
• wherein the tube base further has, for each of the at least one through-opening(s) with
• at least one sealing ring each for sealing the respective tube,
• at least one seal seat each for receiving the at least one sealing ring wherein the seal seat is an indentation in the second tube base plate which surrounds the respective through-opening directly in ring-like manner and for each of the at least one through-openings a tube which passes through the respective through-opening and is sealed in by the at least one seal ring lying in the at least one seal seat.

A method for sealing a shell-and-tube heat exchanger, the method comprising:

• a tube base including a first tube base plate with a core and plastics sheathing surrounding the core,
• a second tube base plate made of a temperature-resistant material, wherein the temperature-resistant material has no substantial flow behaviour for temperatures up to at least 200° C. and no substantial thermal expansion for temperatures between −50° C. and 200° C., and
• a third tube base plate with a core and plastics sheathing surrounding the core,
• wherein the first, second and third tube base plates are stacked to form a stack, wherein the second tube base plate is arranged as an intermediate plate between the first and the third tube base plate, so that a first surface of the second tube base plate is directed towards the first tube base plate and an opposite second surface of the second tube base plate is directed towards the third tube base plate, and wherein the stack comprises at least one through-opening for receiving a respective tube of the shell-and-tube heat exchanger, and
• wherein the tube base further has, for each of the at least one through-opening(s) with
• at least one sealing ring each for sealing the respective tube,
• at least one seal seat each for receiving the at least one sealing ring wherein the seal seat is an indentation in the second tube base plate which surrounds the respective through-opening directly in ring-like manner,
• at least one tube of the shell-and-tube heat exchanger being passed through the corresponding through-opening and sealed in by means of the at least one seal ring lying in the at least one seal seat.