Bending Stress and Deflection This application is related bending stresses and deflection on a uniformly loaded span. The weight of the pipe and product. If there is more than one loading, superimposing individual solutions will be required. To account for unknow stresses multiply the longitudinal stress by 1.1. Fixed End…
Requirements to Move Unpressured Pipe This application is related to maximum movement (deflection) at the end of pipe with no pressure. The greater the deflection requires a larger distance of exposed pipe to minimize the strain on the pipe. PTLB Design & Stress Analysis_2.12 Intro Image.pngππππ₯ β Maximum Stress Allowedππππ…
Hoop and Longitudinal Stress These stresses are used in most calculations for road and RR crossing, spans, blasting, streams, etc. before deciding on the safety of the pipe.Live hoop and longitudinal stress must be below seam and girth weld fatigues limits. Outside force stresses must be known for proper evaluation….
Internal Pressure % SMYS The calculation provides the maximum internal pressure given pipe specs and % SMYS. These factors are used in the design of roads and railroads. Pressure in the pipe i.e. gauge.External loading on the pipe is additive and must be considered separately using PLTB API 1102 external…
Maximum Impact Load & Penetration Depth The focal point of this application is to assess strain due to a falling object such as a piece of construction equipment, material or vehicle falls over an operating pipeline.Some of the limitations of this calculation are as follows: drop height, maximum load at…
Pipe Anchor Force Analysis The following analysis determines stresses and deflections in pipelines at the transition from below ground (restrained) to above ground (unrestrained) to determine if an anchor is required for above-ground pig traps or other piping facilities. Internal pressure, temperature change, the flexibility to absorb a degree of…
Buoyancy Analysis & Concrete Weights Spacing Calculating Buoyance Forces The buoyancy of a pipeline depends upon the weight of the pipe, the weight of the volume of water displaced by the pipe, the weight of the liquid load carried by the pipe and the weight of the backfill. As a…
Flume Design – Rational Method Estimating Roughness Coefficients This section describes a method for estimating the roughness coefficient n for use in hydraulic computations associated with natural streams, floodways, and excavated channels. The procedures apply to the estimation of n in Manning’s formula. The coefficient of roughness n quantifies retardation…
Unstrained Pipeline Stress Analysis Unrestrained pipes are unburied or spans where the pipe is bedded or supported beam. These could be designed or mother nature exposing the pipe due to flooding or other natural causes. Allowable expansion stresses sustained and occasional loads that are greater than 80% stress. Thermal expansion…
Restrained Pipeline Stress Analysis Restrained pipes are typically buried with proper bedding. However, when settlement or subsidence occurs the longitudinal and combined stresses may be replaced with a strain limit of 2% in ASME B31.4 Yielding that does not impair the serviceability of the pipe. Local stresses caused by periodic…