Continuous Thickness Control of Centrifugally Cast Concrete Pipes by an Ultrasonic Echo-System

1968 ◽  
Vol 1 (2) ◽  
pp. 50-52
Author(s):  
J. A. de Raad ◽  
A. de Sterke
Keyword(s):  
Prestressed Concrete ◽  
Large Diameter ◽  
Ultrasonic Pulse ◽  
Centrifugally Cast ◽  
Concrete Pipes ◽  
Ultrasonic Echo ◽  
Cast Concrete ◽  
Large Diameter Pipes ◽  
Pulse Echo ◽  
Made In

Large diameter pipes of prestressed concrete with a length of 10–20 ft. used for water transport are made in rotating moulds. To control the thickness of these concrete pipes during production, an ultrasonic pulse-echo system mounted at the end of the feeder is used. Basically, the air gap between feeder and inner pipe wall is continuously measured, whereby deviations due to misalignment of the feeder are electronically compensated. A prototype version of the system has proved its usefulness. An accuracy of ±5% of the nominal wall thickness was obtained.

Weldability of 15Kh1M1F steel for centrifugally cast large diameter pipes

1992 ◽  
Vol 6 (12) ◽  
pp. 973-977
Author(s):  
F A Khromchenko ◽  
V A Lappa ◽  
T S Frolova ◽  
V V Vaskovskaya
Keyword(s):  
Large Diameter ◽  
Centrifugally Cast ◽  
15Kh1m1f Steel ◽  
Large Diameter Pipes

scholarly journals An Ultrasonic Pulse-Echo Method to Detect Internal Defects in Epoxy Composite Insulation

Energies ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4804 ◽  
Author(s):  
Fangyuan Tian ◽  
Yanpeng Hao ◽  
Zhouyiao Zou ◽  
Yao Zheng ◽  
Weiming He ◽  
...  
Keyword(s):  
Epoxy Composite ◽  
Ultrasonic Pulse ◽  
Propagation Time ◽  
Reflected Waves ◽  
Surface Flashover ◽  
Similar Materials ◽  
Set Up ◽  
Different Diameters ◽  
Pulse Echo ◽  
Made In

Voids or cracks in basin insulators inside a GIS (gas-insulated metal-enclosed switchgear) could trigger partial discharges or surface flashover under electrical stresses, threatening safe GIS operation. For this paper, some epoxy composite specimens were made from similar materials and manufacturing processes to make 252 kV GIS basin insulators. Some voids with different diameters or cracks with different diameters and orientations were artificially made in the specimens with different thicknesses. An ultrasonic pulse-echo system was set up, and ultrasonic tests were carried out on the specimens with voids or cracks. A method to calculate the depth of a defect was proposed by the propagation time of defect reflected waves. The results showed that a depth of 50 mm, a diameter φ of 2 mm void, and a diameter φ of 1 mm crack in epoxy composite insulation were detected by the ultrasonic system using a 1 MHz transducer.

Оценка реальной чувствительности приемочного ультразвукового контроля рельсов

2020 ◽  
pp. 17-27
Author(s):  
А.А. Шелухин
Keyword(s):  
Ultrasonic Pulse ◽  
Piezoelectric Transducers ◽  
Acoustic Path ◽  
Metallic Inclusion ◽  
Inclusion Type ◽  
The Real ◽  
Rail Head ◽  
Pulse Echo

In this article, the analysis of the acoustic path during the ultrasonic pulse echo testing of the rail head in production is carried out. The influence of the parameters of the applied piezoelectric transducers on the distribution of sensitivity for the sounding scheme used in the existing installations is estimated and the real sensitivity of detecting defects of the «non-metallic inclusion» type is estimated.

scholarly journals X-ray Diffraction Analysis and Williamson-Hall Method in USDM Model for Estimating More Accurate Values of Stress-Strain of Unit Cell and Super Cells (2 × 2 × 2) of Hydroxyapatite, Confirmed by Ultrasonic Pulse-Echo Test

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2949
Author(s):  
Marzieh Rabiei ◽  
Arvydas Palevicius ◽  
Amir Dashti ◽  
Sohrab Nasiri ◽  
Ahmad Monshi ◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Ultrasonic Pulse ◽  
High Accuracy ◽  
Unit Cell ◽  
Deformation Model ◽  
X Ray Diffraction ◽  
Uniform Deformation ◽  
X Ray ◽  
Pulse Echo

Taking into account X-ray diffraction, one of the well-known methods for calculating the stress-strain of crystals is Williamson-Hall (W–H). The W-H method has three models, namely (1) Uniform deformation model (UDM); (2) Uniform stress deformation model (USDM); and (3) Uniform deformation energy density model (UDEDM). The USDM and UDEDM models are directly related to the modulus of elasticity (E). Young’s modulus is a key parameter in engineering design and materials development. Young’s modulus is considered in USDM and UDEDM models, but in all previous studies, researchers used the average values of Young’s modulus or they calculated Young’s modulus only for a sharp peak of an XRD pattern or they extracted Young’s modulus from the literature. Therefore, these values are not representative of all peaks derived from X-ray diffraction; as a result, these values are not estimated with high accuracy. Nevertheless, in the current study, the W-H method is used considering the all diffracted planes of the unit cell and super cells (2 × 2 × 2) of Hydroxyapatite (HA), and a new method with the high accuracy of the W-H method in the USDM model is presented to calculate stress (σ) and strain (ε). The accounting for the planar density of atoms is the novelty of this work. Furthermore, the ultrasonic pulse-echo test is performed for the validation of the novelty assumptions.

scholarly journals Determination of the Elastic Tensor of a Textured Low-Carbon Steel

1993 ◽  
Vol 21 (1) ◽  
pp. 3-16 ◽  
Author(s):  
P. Spalthoff ◽  
W. Wunnike ◽  
C. Nauer-Gerhard ◽  
H. J. Bunge ◽  
E. Schneider
Keyword(s):  
Carbon Steel ◽  
Elastic Anisotropy ◽  
Low Carbon Steel ◽  
Elastic Stiffness ◽  
Ultrasonic Pulse ◽  
Grain Structure ◽  
Maximum Deviation ◽  
Low Carbon ◽  
The Hill ◽  
Pulse Echo

The components of the elastic stiffness tensor of hot rolled low-carbon steel were determined using an ultrasonic pulse-echo-method. They were also calculated on the basis of X-ray texture measurements using the Hill approximation. The maximum deviation between experimental and calculated values is 3.5%. An influence of the slightly anisotropic grain structure on the elastic anisotropy could not be seen.

Elastic properties ofGd5Si2Ge2studied with an ultrasonic pulse-echo technique

2006 ◽  
Vol 74 (18) ◽  
Author(s):  
O. Svitelskiy ◽  
A. Suslov ◽  
D. L. Schlagel ◽  
T. A. Lograsso ◽  
K. A. Gschneidner ◽  
...  
Keyword(s):  
Elastic Properties ◽  
Ultrasonic Pulse ◽  
Pulse Echo

Evaluation of the expansion attained to date by concrete affected by alkali–silica reaction. Part III: Application to existing structures

2005 ◽  
Vol 32 (3) ◽  
pp. 463-479 ◽  
Author(s):  
Marc-André Bérubé ◽  
Nizar Smaoui ◽  
Benoit Fournier ◽  
Benoit Bissonnette ◽  
Benoit Durand
Keyword(s):  
Prestressed Concrete ◽  
Alkali Silica Reaction ◽  
Existing Structures ◽  
Concrete Members ◽  
Crack Widths ◽  
Concrete Petrography ◽  
Made In

The expansion attained by a concrete affected by alkali-silica reaction (ASR) is an important parameter in the evaluation of the corresponding structure. In part I, relationships were established in the laboratory between the ASR expansion and the stiffness damage test (SDT), the damage rating index (DRI), and the cumulated width of cracks observed at the surface of concrete specimens made with various types of reactive aggregates. In part II, these relationships were verified in the case of specimens made in laboratory but exposed outdoors. In part III, the aforementioned methods were applied to three ASR-affected structures. The measurement of crack widths at the surface of the affected members allowed a rather good estimation of the concrete expansion, provided the measurements were taken on the most severely exposed sections of these members. The DRI did not allow differentiating the most visually and mechanically affected concretes from the least affected concretes. The SDT proved to be the most interesting method to date for evaluating the expansion of ASR-affected concrete; however, it seemed to underestimate the expansion of the prestressed concrete members investigated.Key words: aggregates, alkali–silica reaction, concrete, petrography, expansion, stiffness, cracking.

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