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渣漿泵機械密封的選用與適用于那種
    (1)強腐蝕性介質:選用外裝式機封或波紋管機封，如果采用內裝式時要對彈簧進行防腐保護措施。對摩擦副材料也應采用耐磨材料，如四氟陶瓷等。
    (2)易汽化介質:選用平衡型或雙端面機械密封。
    (3)含鹽及易結晶介質:選用雙端面機械密封;摩擦副采用硬對硬材料，彈簧采用大彈簧，用沖洗液進行“封堵”措施。
    (4) 含固體顆粒介質:選用雙端面機械密封，靠近介質側選擇靜止內流式結構。摩擦副采用硬對硬材料。沖洗液加旋液分離器或外供沖洗液沖洗。彈簧要采用大彈簧結構。
    (5) 高黏度介質:選用靜止型雙端面機械密封，摩擦副采用硬對硬材料組合。
    (6) 高溫介質:密封材料要進行穩定熱處理，且膨脹系數相近。用單端面機械密封，端面寬度盡量小，需充分冷卻沖洗。采用雙端面機械密封，需外供循環液。溫度超過250C，采用金屬波紋管式機械密封，但要注意金屬波紋管的承壓能力。輔助密封材料也應選擇相應溫度的材料。
    (7)低溫介質:介質溫度高于- 45C時可選用單端面機封。介質溫度高于-100C時，選用波紋管機封。介質溫度低于-100C時， 選用靜止式波紋管機封，波態烴建議選用雙端面機械密封。摩擦副材料選擇青銅填充聚四氟乙烯。輔助密封材料也應該選擇相應溫度的材料。

(8)高壓介質:當壓力p>0.7MPa。應選擇平衡型機封，當壓力較高時， 在保證允許的最小端面比壓條件下，應選擇較大平衡系數，但不大于0.5。當壓力p>15MPa時，宜采用串聯機封，逐步降低沒級密封壓力、摩擦副材料宜用碳化鎢對浸漬金屬石墨，或硬對硬材料，如硬質合金、陶瓷等。O形圈的肖氏硬度應大于80，并用隔離支承圈以防被擠出。

(9)高速:當速度n>25m/s時，采用靜止式機封，動環與軸直接配合利用軸套和葉輪夾緊來傳遞力矩，而不主張用鍵、銷來傳通，以減小不平衡力的影響。要用最小的密封端面摩擦系數，端面寬度盡量小，加強冷卻與潤滑。

(10)正反轉:應采用金屬波紋管機封、或小彈簧結構機械密封。渣漿泵廠家

Selection and application of mechanical seal for slurry pump

(1) strong corrosive medium: external mechanical seal or bellows mechanical seal shall be selected. If internal type is adopted, anti-corrosion protection measures shall be taken for spring. Wear resistant materials, such as Teflon ceramics, should also be used for friction pairs.

(2) vaporizable medium: balanced or double face mechanical seal is selected.

(3) salt containing and crystallizable medium: double face mechanical seal is selected; hard to hard material is used for friction pair, large spring is used for spring, and "plugging" measures are taken with flushing liquid.

(4) medium containing solid particles: double face mechanical seal is selected, and static internal flow structure is selected near the medium side. The friction pairs are made of hard to hard materials. The flushing liquid is added to the liquid separator or supplied to the outside for flushing. The spring shall be of large spring structure.

(5) high viscosity medium: static double face mechanical seal is selected, and hard to hard material combination is used for friction pair.

(6) high temperature medium: the sealing material shall be subject to stable heat treatment with similar expansion coefficient. Use single face mechanical seal, the width of the end face shall be as small as possible, and it shall be fully cooled and flushed. Adopt double face mechanical seal, need to supply circulating liquid. If the temperature exceeds 250C, metal bellows mechanical seal shall be adopted, but the pressure bearing capacity of metal bellows shall be paid attention to. The auxiliary sealing material shall also be selected at the corresponding temperature.

(7) low temperature medium: when the medium temperature is higher than - 45C, single end mechanical seal can be selected. When the medium temperature is higher than - 100C, the bellows mechanical seal is selected. When the medium temperature is lower than - 100C, static bellows mechanical seal is selected, and double face mechanical seal is recommended for wavy hydrocarbon. The material of friction pair is bronze filled polytetrafluoroethylene. The auxiliary sealing material should also be selected at the corresponding temperature.

(8) high pressure medium: when the pressure P > 0.7MPa. Balance type mechanical seal shall be selected. When the pressure is high, under the condition of ensuring the minimum allowable end face specific pressure, a larger balance coefficient shall be selected, but not more than 0.5. When the pressure P > 15MPa, the series mechanical seal should be used to gradually reduce the level of sealing pressure, the tungsten carbide impregnated metal graphite or hard to hard materials, such as cemented carbide, ceramics, etc. should be used as the friction materials. The O-ring shall have a shore hardness greater than 80 and be supported by an isolating ring to prevent extrusion.

(9) high speed: when the speed is n > 25m / s, the static mechanical seal is adopted. The dynamic ring and shaft are directly matched to use the shaft sleeve and impeller to clamp to transmit the torque, instead of the key and pin to transmit, so as to reduce the influence of the unbalanced force. It is necessary to use the minimum friction coefficient of the sealing end face and the width of the end face as small as possible to strengthen the cooling and lubrication.

(10) forward and reverse: metal bellows mechanical seal or small spring structure mechanical seal shall be adopted. Slurry pump manufacturer