DESCRIPTION TECHNICAL FIELD

The invention describes fixture for finalizing split pin alignment for castle nut with design torque for bolt and nut.

BACKGROUND OF INVENTION

Wings are attached to the fuselage of aircraft with the help of nut and bolts. Torque values are provided to ensure proper fastening of these nuts and bolts. Bolts are designed with split pin hole to avoid loosening of nuts due to vibration. For proper alignment of spilt pin hole of the bolt to the castle nut, thickness of washer installed at back side of nut to be change either by machining or by changing to higher thickness. This activity is time consuming as the accessibility on the aircraft is very less.

The new concept will facilitate this activity on ground with a special fixture and will help to reduce cycle time of mating wing with the aircraft fuselage structure.

SUMMARY OF INVENTION

Fixture is designed according to the original aircraft dimensions. Original nuts and bolts used with proper washer are used to get the required torque by tightening with spanners ensuring the alignment of split pin hole. After simulating the assembly positions of bolt and nut with washers, position of the split pin hole on the bolt is finalized and same can be directly used while mating the wing on the to the fuselage structure.

PROCESS DETAIL DESCRIPTION

Fixtures were made with aluminum alloy with steel bushes (Similar to aircraft construction) as shown in figure 1. In this fixture the dimension of the mating surfaces are made with the same drawing tolerance of original wing mounting points which will provide the actual position of the wing mating points. Same concept can be adopted any other locations where difficulty is observed for split pin locking with design torque values.

CLAIMS

We claim,

1. Alignment of split pin hole on bolt for providing accurate torque value can be obtained by torque fixture at inaccessible areas on aircraft.