Becht Engineering Blog

The API Inspection Codes were originally based on failure prevention and did not consider the consequences of failure or potential damage mechanisms.  Risk-based inspection (RBI) assessments result in an equipment risk ranking based on the probability of failure (a leak occurring) and the consequence associated with that leak.  Applied properly, RBI provides the benefit of increasing operating efficiencies and unit run lengths of process facilities while maintaining or reducing the current level of risk. As stated above, risk has two components, probability and consequence.  In risk-based inspection, the probability of failure is determined by evaluating the initial design conditions and the amount of damage that can potentially occur while the equipment is in operation.  Uncertainty in the model is also address by crediting previous inspections.  Consequences are commonly evaluated in terms of environmental, health, and safety impact areas or financial loss (lost opportunity, repair costs, etc.).  Consequences are also evaluated based...

On February 1, 2003 the Space Shuttle Columbia, while entering the earth’s atmosphere at 10,000 miles per hour, disintegrated killing all 7 astronauts. A $4 billion spacecraft was destroyed, spreading debris over 2000 square miles and grounding the Space Shuttle program for 2-1/2 years. The cause, normalization of deviance. Insulating foam strikes which had been unacceptable were tolerated and ignored. The NASA specification stated “No debris will emanate from the critical zone of the external tank on the launch pad or during ascent.” However, after 113 shuttle missions, foam shedding, debris impacts and TPS tile damage came to be regarded as only a routine maintenance concern. Each successful mission reinforced the belief that foam shedding was unavoidable and unlikely to jeopardize safety. On January 28, 1986 the Space Shuttle Challenger exploded killing all astronauts on board and destroying the spacecraft. The cause, normalization of deviance. Increasing problems with o-ring damage were...

As the Nuclear Power Plant workforce continues to age, it is imperative that nuclear plant supervisors and managers use as many tools as possible to mentor younger engineers. This article discusses several ways proven to be successful in mentoring younger engineers as a means of filling the voids created by the retirements of senior workforce individuals. These tools are also be effective in retaining younger engineers. The Aging Workforce It is well known that one of the nuclear power industry’s challenges is addressing its aging workforce. In a 2015 Article [Ref. 1], Power Engineering Magazine cites the following statistics: “The Nuclear Energy Institute estimates that 39 percent of the nuclear workforce will be eligible for retirement by 2018, which means the industry must hire 20,000 new workers over the next four years to replace those retiring workers.” “About 40 percent of the work force at America's electric and natural gas utilities...

The analysis procedures in the Code essentially assume that the strain range in the system can be determined from an elastic analysis. That is, strains are proportional to elastically calculated stresses. The stress range is limited to less than two times the yield stress, in part to achieve this. However, in some systems, strain concentration or elastic follow-up occurs. A typical concern in refinery systems is hot walled sections in otherwise refractory lined piping systems, where thermal expansion loading has resulted in cracking in the hot walled section although it complied with the basic code acceptance criteria. As an example, consider a cantilevered pipe with a portion adjacent to the fixed end constructed with a reduced-diameter or -thickness pipe or lower-yield-strength material that has the free end laterally displaced. The elastic analysis assumes that strains will be distributed in the system in accordance with the elastic stiffnesses. However, consider what happens...