Thin-walled tubes and pipes are employed in industries to work under the conditions of high temperature, high pressure, high flow rates and radiation. Due to such stresses and harsh working conditions, tubes lead to sag during operation because of its low Wall Thickness and smaller diameters. There is a requirement to accurately measure sag and dimensions and assess the health and remaining life of tubes and pipes, as per the relevant safety and reliability standards. Sag measurement is a complex task as it has to be performed in-situ. Other than that there is an important requirement to accurately measure Inner Diameter (ID), Outer Diameter (OD) and Wall Thickness (WT) of tubes and pipes. In this paper, a novel type of linear array-based sag and dimension measurement scheme has been proposed for the thin-walled tubes and pipes using Ultrasonic Testing (UT). UT technique has also been employed to accurately measure the sag and dimensions of the thin-walled tubes and pipes. The operating principle of UT is majorly based on Water-Immersion mode for the measurement of sag and dimensions by acquiring Time of Flight (TOF). In this paper, experimentation has been carried out using an in-house developed 4-Channel Ultrasonic Imaging System and using water-immersion mode. The 4-Channel Ultrasonic Imaging System along with an inspection head carrying a novel arrangement of ultrasonic transducers for measurement of sag and dimensions have been utilized. This paper provides details of the sag and dimension measurement of the sample tube and pipe, using the 4-Channel Ultrasonic Imaging System.

中文翻译：

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使用多通道超声成像系统测量薄壁管材的垂度和尺寸试验

工业上采用薄壁管材，在高温、高压、大流量、辐射等条件下工作。由于这种应力和恶劣的工作条件，管子在操作过程中会因为壁厚小和直径小而导致下垂。根据相关的安全和可靠性标准，需要准确测量垂度和尺寸，并评估管材的健康状况和剩余寿命。垂度测量是一项复杂的任务，因为它必须在原位进行。除此之外，还有一个重要的要求是准确测量管子的内径 (ID)、外径 (OD) 和壁厚 (WT)。在本文中，一种新型的基于线性阵列的垂度和尺寸测量方案已被提出用于使用超声波测试 (UT) 的薄壁管和管道。UT 技术也已用于精确测量薄壁管材的垂度和尺寸。UT 的工作原理主要基于浸水模式，通过获取飞行时间 (TOF) 来测量垂度和尺寸。在本文中，使用内部开发的 4 通道超声成像系统和使用水浸模式进行了实验。4 通道超声成像系统以及带有用于测量垂度和尺寸的新型超声换能器排列的检测头已被使用。本文提供了样品管和管道的垂度和尺寸测量的详细信息，