Control rod housing alignment and repair method

Patent · Tue Apr 07 00:00:00 EDT 1992

OSTI ID:5060949

Dixon, R C; Deaver, G A; Punches, J R; Singleton, G E; Erbes, J G; Offer, H P

This patent describes a method for underwater welding of a control rod drive housing inserted through a stub tube to maintain requisite alignment and elevation of the top of the control rod drive housing to an overlying and corresponding aperture in a core plate as measured by an alignment device which determines the relative elevation and angularity with respect to the aperture. It comprises providing a welding cylinder dependent from the alignment device such that the elevation of the top of the welding cylinder is in a fixed relationship to the alignment device and is gas-proof; pressurizing the welding cylinder with inert welding gas sufficient to maintain the interior of the welding cylinder dry; lowering the welding cylinder through the aperture in the core plate by depending the cylinder with respect to the alignment device, the lowering including lowering through and adjusting the elevation relationship of the welding cylinder to the alignment device such that when the alignment device is in position to measure the elevation and angularity of the new control rod drive housing, the lower distal end of the welding cylinder extends below the upper periphery of the stub where welding is to occur; inserting a new control rod drive housing through the stub tube and positioning the control rod drive housing to a predetermined relationship to the anticipated final position of the control rod drive housing; providing welding implements transversely rotatably mounted interior of the welding cylinder relative to the alignment device such that the welding implements may be accurately positioned for dispensing weldment around the periphery of the top of the stub tube and at the side of the control rod drive housing; measuring the elevation and angularity of the control rod drive housing; and dispensing weldment along the top of the stub tube and at the side of the control rod drive housing.

• Assignee: General Electric Co., San Jose, CA (United States)
• Patent Number(s): US 5102614; A
• Application Number: PPN: US 7-725703
• OSTI ID: 5060949
• Resource Relation: Patent File Date: 3 Jul 1991
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
CONTROL ROD DRIVES
WELDING
MAINTENANCE
REACTOR COMPONENTS
REACTOR CONTROL SYSTEMS
REPAIR
SURVEILLANCE
UNDERWATER OPERATIONS
CONTROL SYSTEMS
FABRICATION
JOINING
220400* - Nuclear Reactor Technology- Control Systems
220200 - Nuclear Reactor Technology- Components & Accessories