Method and apparatus for installing steam boiler tubes

An expansion tool assembly for co-operation with a boiler tube end segment during the installation of that boiler tube end segment in a steam boiler drum wall grooved boiler tube end segment bore, and comprising:

• an actuator subassembly actuated by pressurized primary incompressible fluid, and having an actuator subassembly cylinder, an actuator subassembly piston positioned within said actuator subassembly cylinder, and an actuator subassembly piston rod connected to said actuator subassembly piston and projecting beyond said actuator subassembly cylinder;
• a pressure multiplier subassembly joined to and actuated by said actuator subassembly, and having a seal-carrying tool core element that engages the interior of the boiler tube end segment in sealed relation, that with the boiler tube end segment forms a secondary incompressible fluid containment chamber, and that contains a secondary incompressible fluid filling said secondary incompressible fluid containment chamber;
• and
• a power supply subassembly providing pressurized primary incompressible fluid to said actuator subassembly to move said actuator subassembly piston and further project said actuator subassembly piston rod beyond said actuator subassembly cylinder and into said pressure multiplier subassembly secondary incompressible fluid containment chamber, said actuator subassembly piston rod when further projected beyond said actuator subassembly cylinder by pressurized primary incompressible fluid increasing the pressure of said secondary incompressible fluid by a multiple that is the ratio of the cross-sectional area of said actuator subassembly piston to the cross-sectional area of said actuator subassembly piston rod to thereby force boiler tube end segment metal radially outward and into intimate contact with the surface of the steam boiler drum wall grooved boiler tube end segment bore.