It’s an array of clear tubes, each five milimeters in diameter. The tubes are filled with oil blended with a propietary dye.

这是一组洁净管道阵列，每根管子直径5毫米，其中灌注了混合特种染料的油状液体。

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With a larger diameter, thinner wall, and clear inner diameter (ID) the TDB are used as tube heaters.

TDB作为管状发热器，有着更大的直径，更薄的管壁和更清晰的内径。

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Pigging and caliper with clear pig diameter than pipe diameter usually to interference by 5% to 8%.

清管和测径用的清管器直径通常比管道内径要过盈5%至8%。

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