ASME STP-PT-036 pdf free download

ASME STP-PT-036-2010 pdf free download.BOLTED FLANGED CONNECTIONS IN ELEVATED TEMPERATURE SERVICE.
The early research in design and analysis of bolted joints was conducted in the 1930s and l940s: this work led to flanged joint design rules, such as the ASME Section VIII, [)ivision I, Appendix 2 method that was introduced in the 1940s and has remained largely unchanged since that lime. Other international methods of design have been introduced recently. most notably the CEN EN- 13555 method. However, none of the current methods address design of a bolted joint in the creep range. The requirement for the design of high temperature joints was identified during the initial development of the design methods, but unfortunately a concise design method was never documented in a code or standard. This is somewhat understandable, given the myriad of complexities involved with analyzing the significance of creep on a bolted joint. In fact, the present design methods are also inadequate even when addressing low temperature operation that involves creep and relaxation of the components LII. Unfortunately, even with the more powerful analysis methods available today, the researchers of the l930s actually appeared to be closer to resolving high temperature flange design than more recent research efforts.
In part, this lack of advances in the design of high temperature flanges is probably due to the fact that most flanges do not operate in the creep range for the materials of construction and therefore the vast majority of flanges have given admirable service. In addition, a creep “fitilure” of a flange is most likely to be a relatively small leak which is easily rectified by re-lightening the bolts during operation. Such “failure” does not often warrant management attention and therefore does not garner industry attention as an issue requiring resolution. It may also he easily demonstrated that industry, as a whole, has learned to accept bolted joint leakage 121 and therefore relatively little effort has been directed towards reducing the frequency of joint leakage. The need for improvement in the design of high temperature flanged joints was identified to ASME and this project was funded by ASME. starting in August 2007. to examine the requirements for high temperature (in the flange material creep range) flange design.
The intent of the project is to examine the requirements for high temperature flange design and provide guidance for inclusion of design methods into the modern ASME pressure vessel design codes. Throughout the project, it was kept in mind that high temperature flange joints are a relatively small portion of the flange population. and that improvements in Finite Element Analysis (FEA) and computing power are now to the point where very large non-linear creep problems can be solved relatively easily. Therefore, while the fundamentals of high temperature flange design using code equations were included in the assessment, the initial starting point for the project was to formulate guidelines 11w FEA of the creep problem, based on comparison with relatively scarce flange creep test data. It is recognized that these guidelines may actually be the most appropriate implementation of high temperature flange design, due to the inherently critical nature of most high temperature flanges.
The following literature search looked at fundamental research in high temperature flange joints, especially with respect to papers including experimental verification of results. In addition, the area of the mechanical effects of temperature on bolted flange was included, as any assessment of flange creep must he made at the initial operating stress conditions, rather than at the ambient conditions. In addition, the subject of gasket creep behavior was examined. This subject has had extensive research across a variety of gasket types, hut there is very little tie-in with actual high temperature (creep regime) behavior of the bolted joint.ASME STP-PT-036 pdf download.