DSH 752（IEC 60695）灼熱絲火焰定義

Subject: Definition of a flame for glow wire test

Question:

How is the “Corona-Effect” to be interpreted when performing the Glow Wire Test?

Decision:

During the glow wire test (according to the temperature settings required by the standard), the following phenomena can occur:

1. If a brightly shining flame is observed directly at the test specimen (see picture 1), this is a clear indication of an ignition. Some materials show a colourless transparent flame instead of a bright shiny flame. This is considered to be ignition of the test specimen, if the maximum flaming time allowed by the standard is exceeded.

2. Sometimes, a circular corona can be observed around the tip of the glow wire, see picture 2. This corona consists of ionized gas, predominantly blue in colour and is located in the immediate vicinity of the glow wire. This phenomenon is not considered to be ignition of the test specimen, as long as it does not lead to an ignition of the test specimen according to point 1.

3. Furthermore, ionized gasses can sometimes be noticed along the glow wire (see picture 3). This effect is also not considered to be ignition of the test specimen, as long as it does not lead to an ignition of the test specimen according to point 1.

問題：

在進(jìn)行灼熱絲試驗(yàn)時(shí)，如何解釋“電暈效應(yīng)”？

決定：

在灼熱絲試驗(yàn)過程中（根據(jù)標(biāo)準(zhǔn)要求設(shè)置溫度），可能會(huì)出現(xiàn)以下現(xiàn)象：

1、如果在測試樣品上能直接觀察到明亮的火焰（見下圖），就是明確的著火現(xiàn)象。有些材料會(huì)表現(xiàn)出無色透明的火焰，而不是明亮閃亮的火焰。如果超過了標(biāo)準(zhǔn)允許的最大燃燒時(shí)間，認(rèn)為樣品著火。

2、有時(shí)可以在灼熱絲尖端周圍觀察到一個(gè)圓形電暈（見下圖）。這個(gè)電暈圈由電離氣體組成，主要是藍(lán)色的，位于灼熱絲附近。這種現(xiàn)象只要不像第一點(diǎn)會(huì)導(dǎo)致樣品著火，就不認(rèn)為是著火現(xiàn)象。

3、另外，有時(shí)能沿著灼熱絲看到電離氣體（見下圖）。這種現(xiàn)象只要不像第一點(diǎn)會(huì)導(dǎo)致樣品著火，也不認(rèn)為是著火現(xiàn)象。

提示：

不應(yīng)考慮“電暈效應(yīng)”，“電暈效應(yīng)”不被視為灼熱絲測試標(biāo)準(zhǔn)意義上的火焰。

點(diǎn)擊下方名片，關(guān)注“朱大俠的質(zhì)檢江湖”微信公眾號(hào)，一起來研究安規(guī)吧~