Nonlinear Harmonic Monitoring of Gouged Dents in Pipeline Specimens Under Cyclic Loading

2006 ◽  
Author(s):  
Alfred E. Crouch ◽  
G. Graham Chell
Keyword(s):  
Cyclic Loading ◽  
Signal Strength ◽  
Hazardous Materials ◽  
Line Pipe ◽  
Pipe Surface ◽  
Depth Data ◽  
Southwest Research Institute ◽  
The Us ◽  
Pressure Changes ◽  
Research Institute

The only in-line inspection technology commercially available for quantitative evaluation of gouged dents is the geometry pig which cannot discriminate between gouged and smooth dents and has no sensitivity to re-rounded dents. Southwest Research Institute® (SwRI®), has been funded by the US Pipeline and Hazardous Materials Safety Administration (PHMSA) and the Gas Research Institute (GRI) through the Pipeline Research Council International (PRCI), to determine the capability of the nonlinear harmonic (NLH) method to characterize the severity of gouged dents, including those that have been re-rounded by internal pressure. This paper describes the NLH method and presents a summary of results from previous work involving burst tests of gouged dents in 24” pipe as a precursor to the current work that involves experiments with four pressure chambers made from 12-inch line pipe under cyclic pressure changes. In each case, internal scanner hardware, driven from outside the pipe, deployed NLH probes against the pipe inner surface, the gouges being on the outer surface. Analysis of the mapped NLH signals on the inner pipe surface revealed residual strain patterns in the pipe and the strain anomalies produced by gouging. The strain anomalies clearly indicated the presence of the gouges on the outside surface, even when they had re-rounded. The signal maps also indicated the length and width of the gouges whereas the signal strength indicated the residual depth. Data are presented showing that the NLH method is capable of ranking the severity of pipeline gouged dents and their propensity for failure under cyclic loading.

Uncertainty Characterization of the CrCOD Circumferential Crack Opening Displacement Module for xLPR

2015 ◽  
Author(s):  
Richard Olson ◽  
Paul Scott
Keyword(s):  
Crack Opening Displacement ◽  
Crack Opening ◽  
Opening Displacement ◽  
Crack Face ◽  
Pipe Surface ◽  
Circumferential Crack ◽  
The Us ◽  
Experimental Values ◽  
Metal Weld

The US NRC/EPRI xLPR (eXtremely Low Probability of Rupture) probabilistic pipe fracture analysis program uses deterministic modules as the foundation for the calculation of the probability of pipe leak or rupture as a consequence of active degradation mechanisms, vibration or seismic loading. The circumferential crack opening displacement module, CrCOD, estimates crack opening displacement (COD) at the inside pipe surface, at the mid-wall thickness location, and at the outside pipe surface using a combined tension/crack face pressure/bending GE/EPRI-like solution. Each module has an uncertainty beyond the uncertainty of the xLPR data inputs. This paper documents the uncertainty for CrCOD. Using 36 pipe fracture experiments, including: base metal, similar metal weld, and dissimilar metal weld experiments; bend only and pressure and bend loading; static and dynamic load histories; cracks that range from short to long, the uncertainty of the CrCOD methodology is characterized. Module uncertainty is presented in terms mean fit and standard deviation between prediction and experimental values.

Southwest Research Institute intensified detector development capability

2012 ◽  
Author(s):  
Erik Wilkinson ◽  
Michael Vincent ◽  
Christopher Kofoed ◽  
John Andrews ◽  
Judith Brownsberger ◽  
...  
Keyword(s):  
Southwest Research Institute ◽  
Development Capability ◽  
Research Institute

Permeable Coatings and CP Compatibility

2002 ◽  
Author(s):  
Tom Jack ◽  
Fraser King ◽  
Yufeng Cheng ◽  
Robert Worthingham
Keyword(s):  
External Surface ◽  
Protective Coatings ◽  
Impact Damage ◽  
Steel Corrosion ◽  
Barrier Properties ◽  
Surface Coatings ◽  
Line Pipe ◽  
Pipe Surface ◽  
High Impedance ◽  
Environmentally Assisted Cracking

Protective coatings applied to the external surface of line pipe are designed to protect the underlying steel from corrosion over the life of the installation. These coatings are usually used in combination with cathodic protection (CP) to ensure that the steel exposed by coating damage or defects remains protected. The ultimate success of this approach very much depends on the nature, performance and failure mode of the coating. Disbondment of a high impedance coating such as a polyolefin tape can block CP while allowing water access to the underlying steel. Corrosion and near neutral pH SCC can result. In contrast, pinholes or impact damage on coatings such as fusion bonded epoxy allow both CP and water to penetrate to the pipe surface. Coatings that become permeable in service such as asphalt enamels similarly allow protection of the pipe despite a general loss of barrier properties. Because no corrosion or environmentally assisted cracking occurs where adequate CP potentials are sustained, these coatings can be regarded as being “CP compatible”.

scholarly journals Worker Protection Standard: Requirements for Agricultural Employers of Workers and Handlers

EDIS ◽  
2018 ◽  
Vol 2018 (1) ◽  
Author(s):  
Frederick M. Fishel
Keyword(s):  
Environmental Protection ◽  
Environmental Protection Agency ◽  
Hazardous Materials ◽  
Protection Agency ◽  
Agricultural Pesticides ◽  
The Us ◽  
High Concern

Safety is a high concern for agricultural employers whose workers deal with hazardous materials, such as pesticides. In 1992, the US Environmental Protection Agency (EPA) issued the Worker Protection Standard for Agricultural Pesticides (WPS), a regulation that requires agricultural employers to take steps to reduce pesticide-related risks for their workers and handlers. This five-page document describes the responsibilities of employers who must adhere to the WPS. Written by Frederick M. Fishel and published by the UF/IFAS Agronomy Department, January 2018. http://edis.ifas.ufl.edu/ag417

A Summary of Biofuel Pipeline Activities and Progress in the U.S.

2010 ◽  
Author(s):  
Robert Smith
Keyword(s):  
Air Quality ◽  
Hazardous Materials ◽  
State Agencies ◽  
First Responder ◽  
The Us ◽  
Us Government ◽  
Regulatory Barriers ◽  
Government Production ◽  
The U.S

The US Government has mandated the production and usage of biofuels to help reduce dependence on foreign petroleum and to help improve air quality. Partnerships between the Pipeline and Hazardous Materials Safety Administration, the pipeline industry, other Federal and State agencies and the emergency first responder community are rapidly addressing infrastructure challenges and removing the technical and regulatory barriers for transporting biofuels. These initiatives are critical for enabling biofuel usage to grow nationwide and reach government production targets. This paper will summarize recent biofuel activities and discuss the progress seen in removing challenges for safely moving biofuels in the pipeline infrastructure.

Ring Expansion Testing Innovations: Hydraulic Clamping and Strain Measurement Methods

2020 ◽  
Author(s):  
William Walsh ◽  
Sandeep Abotula ◽  
Bharath Konda
Keyword(s):  
Tensile Testing ◽  
Point Contact ◽  
Ring Expansion ◽  
Hydraulic Pressure ◽  
Stress Strain ◽  
Line Pipe ◽  
Pipe Surface ◽  
Expansion Test ◽  
Round Bar ◽  
Dial Indicator

Abstract Ring expansion testing is one of the three accepted methods in API 5L for the measurement of yield strength for line pipe. The other two are flattened-strap tensile testing and round-bar tensile testing. A novel-concept ring expansion test machine has recently been commissioned which uses hydraulic pressure to clamp the top and bottom pressure-reacting plates rather than a traditional bolting arrangement. The benefit of hydraulic clamping is vastly reduced set-up times. This paper describes the design approach and the pitfalls that were overcome in commissioning the ring expansion test unit. Expansion measurements are taken using two different methods: a chain extensometer and an LVDT with a band wrapping the circumference of the pipe. Both approaches are used simultaneously to generate and compare two stress-strain curves for one pressure test. In addition, a 3-Point contact approach is developed to determine the hoop strain during pipe expansion. The 3-point contact approach is an attempt to infer the full hoop expansion behavior by measuring the radius change over a segment of the circumference. The device has two rollers which contact the pipe surface while a dial indicator midway between measures the radius change. As the pipe expands, the rollers maintain contact with the pipe surface while the dial indicator records the change in radius. Tests are performed on HFI, SAWL, and SAWH pipes ranging in outer diameter from 20-inch (508 mm) to 48-inch (1219 mm) and wall thicknesses from 0.375-inch (9.5 mm) to 0.969-inch (24.4 mm). The differences in the stress-strain behavior of these pipe forms are described and related to the residual-stress profiles generated by their respective manufacturing operations. The comparison to flattened-strap and round-bar tensile results are presented in a companion paper. The results of the 3-Point contact approach show that the radius change during early stages of expansion are not uniform around the pipe circumference and different patterns are observed in the HFI, SAWL, and SAWH pipe forms.

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