Compressor cylinder bore misalignment can cause failures that are often not attributed to misalignment. Crosshead shoes uneven wear, compressor piston rod failure at both the crosshead and at the piston, compressor piston rod coating failure, piston wear and compressor cylinder bore wear can all be attributed to cylinder misalignment. The objective of this article is […]
A lesson from the Fukushima Dai-Ichi accident – The series of events that followed the March 11, 2011 tsunami caused hydrogen explosions that damaged the reactor buildings of three units at Fukushima Dai-ichi. In June 2013, the US NRC issued order EA-13-109 “Order to Modify Licenses with Regard to Reliable Hardened Containment Vents Capable of […]
I was the Principal Investigator for the recently issued EPRI Technical Report “Guidelines for the Evaluation of Cracks in Cement Linings and Coatings”, Technical Report 3002000599, December 2013. I worked with EPRI’s Doug Munson to develop these guidelines to help nuclear plant utility engineers make fitness-for-service assessments of damage in cement-lined and cement-coated pipes. Cement […]
When planning or performing a wall thickness inspection of buried pipe, it is necessary to establish the procedure to be used in evaluating the thickness readings, and determine the pipe’s fitness-for-service (FFS), which will be the basis of run-or-repair decisions. We are currently working with EPRI to develop such a procedure. This article is intended […]
Buried steel pipe is prone to pitting due to external (soil-side) corrosion and internal (water-side) corrosion and biofouling. Preventive and mitigative measures include periodic inspection, cleaning, chemical and biocide treatments, and repairs. A cost-effective alternative consists in replacing the buried steel pipe with a non-metallic pipe, in particular high density polyethylene (HDPE). This alternative, widely […]
It is often unsettling to have an inspection group discover a crack-like flaw in a piece of pressure containing equipment, particularly when the turn-around schedule is aggressive. Fortunately, there are well-established Fitness-for-service procedures in place to assess such flaws and help guide decision-making on whether to repair or to leave in place with a monitoring […]
Fired Heaters come in many types and configurations: catalytic reformers, crude heaters, visbreakers, vacuum heaters, coker heaters, etc; and many are prone to carburization damage (i.e. residual carbon diffusing into the tube material, causing damage or even failure). Many refineries today use delayed coking processes to upgrade their crude product. This process includes the use […]
Appendix P was written to introduce piping flexibility analysis rules that are more suitable for computer piping flexibility analysis, in contrast to the rules in the base Code which were written when piping analysis was done by hand calculations. Most of the elements of Appendix P have been, or are proposed to be, added to […]
While fracture mechanics is used in fitness-for-service, FFS, for evaluation of crack like flaws that are detected and for evaluation of the potential for brittle fracture, it is also used in new design to evaluate fatigue life. The rules for high pressure vessels in Section VIII, Div 3 and ASME B31.3 Chapter X permit and […]
The pressure vessel and piping jurisdiction in Alberta, Canada is ABSA – the pressure equipment safety authority. All pressure equipment as defined by the provincial Safety Codes Act must be registered with ABSA. I have been involved in registering piping systems and pressure vessels in this, my home jurisdiction. The focus of this blog […]
