A nuclear reactor having a control rod drive mechanism assembly positioned therein, the nuclear reactor having a reactor vessel, a reactor core, and a reactor vessel head, the nuclear reactor control rod drive mechanism, comprising: a rod control cluster assembly; a drive rod assembly connected to the rod control cluster assembly and structured to vertically move said rod control cluster assembly; a rod travel housing having a first end and a second end, and comprising a cylindrical tube to house said drive rod assembly; characterized by an integrated component absent of a threaded connection and absent of a canopy seal weld, attached to the reactor vessel head, comprising: a latch housing nozzle having a first end and a second end, the first end of the latch housing nozzle attached to the reactor vessel head; and a latch housing having a first end and a second end, the first end of the latch housing integrated with the second end of the latch housing nozzle by an integration mechanism selected from the group consisting of a bimetallic weld and pre-fabrication to form a single component; a latch assembly positioned within the latch housing and connected to the first end of the rod travel housing; a threaded connection, the first end of the rod travel housing being threaded into the second end of the latch housing; a canopy seal weld, the first end of the rod travel housing being welded to the second end of the latch housing; and an end cap connected to the second end of the rod travel housing absent a canopy seal weld. a rod control cluster assembly; a drive rod assembly connected to the rod control cluster assembly and structured to vertically move said rod control cluster assembly; a rod travel housing having a first end and a second end, and comprising a cylindrical tube to house said drive rod assembly; characterized by an integrated component absent of a threaded connection and absent of a canopy seal weld, attached to the reactor vessel head, comprising: a latch housing nozzle having a first end and a second end, the first end of the latch housing nozzle attached to the reactor vessel head; and a latch housing having a first end and a second end, the first end of the latch housing integrated with the second end of the latch housing nozzle by an integration mechanism selected from the group consisting of a bimetallic weld and pre-fabrication to form a single component; a latch housing nozzle having a first end and a second end, the first end of the latch housing nozzle attached to the reactor vessel head; and a latch housing having a first end and a second end, the first end of the latch housing integrated with the second end of the latch housing nozzle by an integration mechanism selected from the group consisting of a bimetallic weld and pre-fabrication to form a single component; a latch assembly positioned within the latch housing and connected to the first end of the rod travel housing; a threaded connection, the first end of the rod travel housing being threaded into the second end of the latch housing; a canopy seal weld, the first end of the rod travel housing being welded to the second end of the latch housing; and an end cap connected to the second end of the rod travel housing absent a canopy seal weld.