The paper presents an exact analytical solution using higher order functions for the deflection and buckling of a simple pipe stand in a derrick, modeled as an inclined slender column, with self-weight and pinned at both ends. The results are consistent with industry practice where an intermediate finger board is used to support 93 ft stands of both 2.3/8?and 2.7/8?steel pipe but is not required for 3.1/2?pipe. These observations suggest a suitable safety factor for application in other cases. The results are an important limiting case for the general pipe stand model presented in part 2. Buckling lengths are presented for a range of pipe sizes and types. Sensitivities, such as the presence of tool joints, differences in material, wear and the effect of pipe stick-up above the top racking board are also introduced. The model is applied to 124 ft pipe stands and an anecdote from Trinidad operations in the mid 1960抯 suggests that secondary buckling modes have been encountered. Although rare, these secondary modes are barely stable and a rapid and dangerous release of elastic energy occurs when the mode changes. Construction columns are normally designed to support significant loads and in most cases self-weight plays only a minor role. This is not the case for a simple pipe stand in a derrick which stability is solely dependent on self-weight. More formal analysis of these conditions is warranted because of the trend of increased mechanisation and the need to preserve safety whilst improving operational efficiency. To the author抯 knowledge there is no existing industry guidance for the flexing and stability of pipe stands in a derrick.
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