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渣漿泵機械密封的材料分那幾種規格

(1) 摩擦副材料

①石墨浸漬:可以是純石墨或石墨浸漬樹脂或浸漬金屬。石墨有良好的自潤滑性和導熱性，摩擦系數低，耐腐蝕，并有好的加工性，但它的缺點是機械強度低，耐溫低。浸演后的石墨比純石墨強度提高很多，浸漬酚醛樹脂用于溫度低于170C，呋喃樹脂、環氧樹脂用于溫度低于200%。浸金屬石墨不但強度好，并可耐較高溫度，浸青銅、鋁、鉛、銻、巴氏合金等，溫度可達400C。

    ②聚四氟乙烯:有優異的耐腐蝕性，但具有機械強度較低、耐磨性不高、剛性差、彈性小、線膨脹系數隨溫度增大等缺點，所以常加填充玻璃纖維、二 硫化鉬、石墨及各種金屬加以改進。
    ③酚醛塑料:它有較好耐酸性、耐磨性、成本低，但它質脆，不耐堿腐蝕，使用溫度低于120C。
    ④氧化鋁陶瓷:它具有很高的硬度及耐磨性，耐腐蝕性也很強，價格低，但脆性大，機械加工困難。  
    ⑤硬質合金:硬度高，強度高，耐磨性，耐腐蝕，抗沖刷性好，可用于< 500C的場合，但其價格較高。采用堆焊、鑲環的方法，可降低成本，但容易產生缺陷，鑲環在高溫中易脫落、變形等。
    ⑥碳化鎢硬質合金:碳化鎢是由硬度極高的難熔金屬碳化物加粘結劑用粉末冶金方法壓制燒結而成。具有極高的硬度和強度，極好的耐磨性，抗顆粒沖刷性和耐腐性，線膨脹系數較低。但材料脆性大，機械加工困難。  
    ⑦青銅:常用的是磷青銅、錫青銅，其彈性模數大，導熱性好，加工性好，它對硬質材料有順磨性。但質軟，耐腐蝕性差。適用油類等中性介質，特別適用于海水，不適用于有固體顆粒的介質。
    ⑧高硅鑄鐵:具有較高的硬度，在強氧化性酸中有很高的耐腐蝕性，但不耐堿和氫氟酸，并且質脆，耐沖擊性能差，機械加工困難。

⑨碳化硅陶瓷、氮化硅陶瓷:屬于新型陶瓷，硬度高于氧化鋁陶瓷，耐磨性，耐熱性，耐蝕性，更優于氧化鋁陶瓷，摩擦系數低，可用于各種無機酸和有機溶劑。
(2)輔助密封圈材料

①天然橡膠:使用溫度- 50~ 120C。其彈性和低溫性能好，但不耐高溫，不耐油，易老化。一般用于溫度不高的水中。
    ②丁苯橡膠:使用溫度- 30~120C。耐磨，耐老化，價格低，彈性好。不耐礦物油，但耐動、植物油。一般用于水、 動植油及酒精類介質，不能用于礦物油。
    ③丁腈橡膠:使用溫度-30~ 120C。耐油，耐磨，耐老化，但不耐高溫，應用很廣泛?？捎糜谌剂嫌?、礦物油和水中。

④硅橡膠:使用溫度-70 ~250C。耐高溫，耐低溫，也耐油。但機械強度差，僅為丁腈橡膠的1/3，并且耐腐蝕性較差。適用于高溫、低溫介質中使用。不適用于苯、丙酮類介質。
    ⑤氟橡膠:使用溫度-20~ 250C。耐高溫，耐腐蝕，耐油，耐真空性。但耐低溫較差，膨脹系數大，價格高。適用于高溫、腐蝕的場合，不適用于酮類溶劑。
    ⑥填充聚四氟乙烯:使用溫度- 100 ~250C。有優異的化學穩定性，耐油，耐高溫，耐低溫，耐溶劑，抗老化等。但彈性差，膨脹系數大，溫度不高時易泄漏。適用于高溫，低溫，酸、堿溶劑等強腐蝕性介質。
    ⑦柔性石墨:使用溫度- 200 ~ 100C。其耐溫性，耐腐蝕性極其優良，是一種新型材料，能使用在所有介質中。

(3)彈簧材料

①磷青銅：防磁性，適用于海水和油類介質中，但不耐腐蝕。

    ②碳素彈簧鋼：價格低，適用于無腐蝕性介質中。

③不銹鋼:可用于腐蝕性介質中。  渣漿泵廠家

Material of mechanical seal

(1) friction pair material

① graphite impregnation: it can be pure graphite or graphite impregnated resin or impregnated metal. Graphite has good self-lubricating and thermal conductivity, low friction coefficient, corrosion resistance and good processability, but its disadvantages are low mechanical strength and low temperature resistance. The strength of graphite after impregnation is much higher than that of pure graphite. The temperature of impregnated phenolic resin is lower than 170C, and that of furan resin and epoxy resin is lower than 200%. Impregnated graphite not only has good strength, but also can withstand high temperature. It can be impregnated with bronze, aluminum, lead, antimony, Babbitt alloy, etc. the temperature can reach 400C.

② polytetrafluoroethylene: it has excellent corrosion resistance, but it has the disadvantages of low mechanical strength, low wear resistance, poor rigidity, small elasticity, linear expansion coefficient increasing with temperature, etc., so it is often filled with glass fiber, molybdenum disulfide, graphite and various metals for improvement.

③ phenolic plastic: it has good acid resistance, wear resistance and low cost, but it is brittle and alkali resistant, and the service temperature is lower than 120c.

④ alumina ceramics: it has high hardness and wear resistance, strong corrosion resistance and low price, but it is brittle and difficult to machine

⑤ cemented carbide: high hardness, high strength, wear resistance, corrosion resistance and erosion resistance. It can be used in occasions of < 500C, but its price is high. The method of overlay welding and inlay ring can reduce the cost, but it is easy to produce defects, and inlay ring is easy to fall off and deform in high temperature.

(6) tungsten carbide: tungsten carbide is made of refractory metal carbide with high hardness and binder by powder metallurgy. It has high hardness and strength, excellent wear resistance, particle erosion resistance and corrosion resistance, and low coefficient of linear expansion. But the material is brittle and difficult to machine

⑦ bronze: commonly used are phosphor bronze and tin bronze, which have large elastic modulus, good thermal conductivity and processability, and are smooth to hard materials. But it is soft and has poor corrosion resistance. It is suitable for neutral medium such as oil, especially for sea water, not for medium with solid particles.

⑧ high silicon cast iron: it has high hardness, high corrosion resistance in strong oxidizing acid, but it is not resistant to alkali and hydrofluoric acid, and it is brittle, poor impact resistance, and difficult to machine.

⑨ silicon carbide ceramics and silicon nitride ceramics: they are new ceramics, with higher hardness than alumina ceramics, wear resistance, heat resistance and corrosion resistance, better than alumina ceramics, low friction coefficient, and can be used for various inorganic acids and organic solvents.

(2) auxiliary seal ring material

① natural rubber: service temperature - 50 ~ 120c. It has good elasticity and low temperature performance, but it is not resistant to high temperature, oil and aging. Generally used in water with low temperature.

② styrene butadiene rubber: service temperature - 30 ~ 120c. Wear resistant, aging resistant, low price, good elasticity. Not resistant to mineral oil, but resistant to animal and vegetable oil. It is generally used in water, animal and vegetable oil and alcohol media, but not in mineral oil.

③ NBR: service temperature - 30 ~ 120c. Oil resistant, wear-resistant, aging resistant, but not high temperature resistant, widely used. It can be used in fuel oil, mineral oil and water.

④ silicone rubber: service temperature - 70 ~ 250C. Resistant to high temperature, low temperature and oil. But the mechanical strength is poor, only 1 / 3 of NBR, and the corrosion resistance is poor. Suitable for use in high and low temperature medium. Not suitable for benzene and acetone media.

⑤ fluororubber: service temperature - 20 ~ 250C. High temperature, corrosion, oil and vacuum resistance. But it has poor low temperature resistance, large expansion coefficient and high price. It is suitable for high temperature and corrosion, not for ketone solvent.

⑥ filled with polytetrafluoroethylene: service temperature - 100 ~ 250C. It has excellent chemical stability, oil resistance, high temperature resistance, low temperature resistance, solvent resistance, anti-aging and so on. But it is easy to leak when the temperature is not high. Suitable for high temperature, low temperature, acid, alkali solvent and other corrosive media.

⑦ flexible graphite: service temperature - 200 ~ 100C. It has excellent temperature and corrosion resistance. It is a new material and can be used in all media.

(3) spring material

① phosphor bronze: anti magnetic, suitable for sea water and oil medium, but not resistant to corrosion.

② carbon spring steel: low price, suitable for non corrosive medium.

③ stainless steel: it can be used in corrosive medium Slurry pump manufacturer