BXJ LUBRICATED FISHING BUMPER SUB

Working Principle

● Energy conversion in jarring operation

Downward jarring forced is achieved through the conversion of stored energy     to kinetic energy. When lift load is applied to the drill stem, the bumper jar is pulled open to a certain height creating a potential energy. As higher lift load is applied, the drill stem begins to accumulate stored strain energy due to the spring extension. Sudden release of the lift load will convert the stored strain energy     in the drill stem to a downward acceleration force. As the drill stem accelerate downwards, the bumper jar is released towards its closed position, releasing its potential energy. At this instant, both released energies combine, creating a large downward jarring force.

● Main factors that influence the jarring force

Hanging weight on top of drill stem with the bumper jar. Higher hanging weight will create higher jarring force.

Length of spring extension of the drill jar. Longer length of spring extension during lifting will provide a greater jarring force.

Stroke length of the bumper jar. Longer stroke length will provide a bigger jarring force.

Specifications - BXJ Lubricated Fishing Bumper Sub