Patent ID: 6986298

Claim:
A method of assembly of at least two parts of an object with one another, comprising the steps of introducing a bolt having a thread into the parts so that a free end of the bolt extends outwardly beyond at least one side of the parts; placing on the free end of the bolt a washer having a body and being provided with a first bearing face surface located at one axial side and adapted to cooperate with a nut, a second bearing face surface located at an opposite axial side and adapted to cooperate with the object, and at least one turning resistant surface adapted to cooperate with the thread of the bolt; threadingly connecting the nut to the free end of the bolt so as to abut against the washer; placing a power tool so as to turn the nut with a rotatable element of the power tool connected to the nut to tighten or loosen the bolt and applying a non-rotatable element of the power tool to the washer to absorb a reaction force; and providing the body of the washer with a breaking point arranged so that when the nut is turned and turns the bolt said body of the washer stops the bolt from turning by the turning resistant surface and thereby the nut creates a pull on the bolt which elongates the bolt in an axial direction and applies to said body of the washer an axial force which breaks at said breaking point a portion of said body of the washer and allows said portion of said body of the washer to be pulled axially when the bolt elongates.