自拍露脸借贷宝视频

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不同材質暖氣片有哪些優缺點？

不同材質暖氣片有哪些優缺點？聖蒂羅瀾暖氣片專家幫大家分析：

鑄鐵暖氣片

優點

1、使用壽命較長；

2、價格低廉；

3、可用于蒸汽供暖；

針對于PH值在10—12的北方采暖水質，有較大適用範圍。

缺點

1、生産條件差、能耗大、環境汙染嚴重、工藝落後；

2、在供熱體制改革、推行分戶計量和室溫調控時被禁止使用，因爲鐵鏽會使熱量表和溫控閥失靈或損壞；

3、體積笨重，占地空間大，生産技術落後，不符合節能、環保的要求，已被列爲我國現時期正在逐步取締的産品。

鋼制暖氣片

優點

1、較爲節能，易加工；

2、熱性能好，工作壓力較高；

3、重量適中，搬運安裝方便。

缺點

1、鋼板及鋼管因材質不同，在加工和耐蝕性能方面差異極大；

2、不同鋼管焊接而成，焊縫多，且焊接處不易做好。同時由于彎曲造型，彎曲處管壁變薄，存在隱患；

3、管柱型散熱器依靠其管柱外壁進行傳熱，傳熱面積小；

銅鋁複合暖氣片

優點

以銅、鋁兩種材質爲原料，與供暖系統水接觸的管路爲銅制，其外壁爲鋁制。銅較耐腐蝕，銅鋁傳熱性能好；

缺點

1、上下聯箱因焊接後銅材變軟；

2、銅鋁複合的緊密度：因熱膨脹系數不同，導致熱傳導衰減，噪音問題；

3、水中氯離子易對銅形成點腐蝕；另外，硫酸根離子把銅氧化成硫化物，水中硫化物的存在也是銅的主要腐蝕原因，而在焊接處因焊接形成的電位差造成的電化學腐蝕，且銅管較薄，這就容易在焊接處滲漏。

以上是聖蒂羅瀾散熱器专家为大家总结的不同材质暖气片的优缺點，希望对大家有所帮助。

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Norah brought him over the typed letter. "We walked by the side of our teams or behind the wagons, we slept on the ground at night, we did our own cooking, we washed our knives by sticking them into the ground rapidly a few times, and we washed our plates with sand and wisps of grass. When we stopped, we arranged our wagons in a circle, and thus formed a 'corral,' or yard, where we drove our oxen to yoke them up. And the corral was often very useful as a fort, or camp, for defending ourselves against the Indians. Do you see that little hollow down there?" he asked, pointing to a depression in the ground a short distance to the right of the train. "Well, in that hollow our wagon-train was kept three days and nights by the Indians. Three days and nights they stayed around, and made several attacks. Two of our men were killed and three were wounded by their arrows, and others had narrow escapes. One arrow hit me on the throat, but I was saved by the knot of my neckerchief, and the point only tore the skin a little. Since that time I have always had a fondness for large neckties. I don't know how many of the Indians we killed, as they carried off their dead and wounded, to save them from being scalped. Next to getting the scalps of their enemies, the most important thing with the Indians is to save their own. We had several fights during our journey, but that one was the worst. Once a little party of us were surrounded in a small 'wallow,' and had a tough time to defend ourselves successfully. Luckily for us, the Indians had no fire-arms then, and their bows and arrows were no match for our rifles. Nowadays they are well armed, but there are[Pg 41] not so many of them, and they are not inclined to trouble the railway trains. They used to do a great deal of mischief in the old times, and many a poor fellow has been killed by them." 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