Reliability of equipment during well construction is necessary. Failure of components increases non-productive time and may cause injuries or loss of life. The jar is a component used in well construction, usually as part of the drill string to free stuck pipe or during fishing. It is subject to impact loads due to the hammering and tensile loads caused due to hook loads on the drill string. In this work, a root cause is failure analysis of failed component. The failure is different from all the other cases due to the reason that most of the time the component collapses and rather fails completely. The main objective is to find the root cause of failure. The visual inspection indicates signs of tensile and brittle failure. The scanning electron microscope analyses show evidence of fatigue: the classic beach mark striations. The presence of aluminum and voids in the section show that the material used for manufacture was of low quality. In this paper, efforts are made to provide recommendations to the company that rents these jars. The various causes of failure mentioned can be useful to have better understanding and control of the manufacturing process, improved instructions for the use of the jar, improve the overall reliability of the component, and use it for well construction with the safety of personnel and minimum non-productive time.
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