Our Restorting Force Test is a force used by centralizer against the casing keep it away from the bore hole wall. This test is performed with pipe A & Pipe B with in 5 degrees of horizontal. External force is applied to the outer pipe B which is transferred to the centralizer. Load is applied & load deflection reading are recorded of 3 times when the less restoring force has been obtained. Every spring is tested and the final load deflection curve is made by using the arithmetic average of the force reading at corresponding deflection. Restoring force is knowing from the curve at 675 stand off ratio. Field experience shows that stand off valves of 75- 90% are adequate even in horizontal wells.