Resistance weld repairing of casing flange holes

A method for repairing one or more degraded bolt holes in a metallic flange of a metallic casing, the flange having first and second sides using resistance welding, the method comprising the following steps:

• a) reaming or cleaning and removing at least some corrosion on insides and around degraded bolt holes to form reamed holes;
• b) mounting the casing on a rotatable table of or associated with a resistance welding machine and so that the metallic casing flange floats relative to upper and lower electrodes of a welding machine;
• c) radially and axially clamping an area of the flange surrounding the reamed hole;
• d) placing upper and lower filler slugs in the reamed hole;
• e) placing the upper and lower electrodes against the upper and lower filler slugs and applying a welding current through the upper and lower electrodes while applying pressure to the upper and lower filler slugs with the upper and lower electrodes and resistively heating and melting the upper and lower filler slugs respectively to form a weldment;
• f) the applying welding current includes pulsing the welding current on and off a first number of cycles;
• and
• g) repeating steps c) through f) for each of the reamed holes using the rotatable table to position each of the reamed holes with respect to the upper and lower electrodes.

A welding arrangement for performing repairs of degraded bolt holes in a metallic flange of a metallic casing, the arrangement comprising:

• a casing mounted on a rotatable table of or associated with a resistance welding machine,
• the casing fixtured in a floating fixture mounted on the table so that the metallic casing flange of the casing floats relative to upper and lower electrodes of he welding machine,
• radial and axial clamps radially and axially clamping respectively an area of the flange surrounding a reamed hole,
• upper and lower filler slugs disposed in the reamed hole,
• upper and lower electrodes against the upper and lower filler slugs,
• the resistance welding machine operable for applying a welding current through the upper and lower electrodes while applying pressure to the upper and lower filler slugs with the upper and lower electrodes,
• the resistance welding machine operable for resistively heating and melting the upper and lower filler slugs respectively to form a weldment, and
• the resistance welding machine operable for pulsing the welding current on and off a first number of cycles.