The corrosive action eats into the tube metal, removing iron and resulting in thinner tube walls.

腐蝕作用會侵蝕管道金屬，去除鐵質，導致管壁變薄。

If this action is allowed to continue, certain tubes will fail and will rupture, as the thinner section of tube can no longer withstand the internal operating pressure.

如果任由這種作用持續下去，某些管子就會失效和破裂，因為較薄的管段無法再承受內部工作壓力。

The removed metal, products of corrosion, can also cause a problem, as this material now increases the total quantity of solids contained in the boiler water.

去除的金屬、腐蝕產物也會造成問題，因為這些物質會增加鍋爐水中所含的固體總量。

As we know, this can increase the probability of deposits and scale formation on the inside wall of the tubes.

我們知道，這會增加管道內壁沉積物和水垢形成的機率。

So what are the conditions that cause corrosion and loss of metal inside the boiler drums and boiler tubes?

那麼，導致鍋爐汽包和鍋爐管內金屬腐蝕和損失的條件是什麼？

Well, there are basically three independent causes of corrosion, and they are Acid attack, which occurs when the boiler water is in an acidic condition, that is, low pH.

基本上，腐蝕有三種獨立的原因，它們是 當鍋爐水處於酸性條件下，即 pH 值較低時發生的酸性侵蝕。

Caustic attack, which occurs when the alkalinity of the boiler water is too high.

苛性鹼侵蝕，當鍋爐水的鹼度過高時就會發生。

The pH level is above about 10.5.

pH 值高於約 10.5。

The presence of dissolved gases such as oxygen and carbon dioxide in the boiler water.

鍋爐水中存在氧氣和二氧化碳等溶解氣體。