??適用范圍:化工泵、清水泵、污水泵、廢水泵、油泵
??適用行業(yè):煉鋼、造紙、化工、電力、水泥行業(yè)等
??適用主機(jī):上海凱泉泵業(yè)
??結(jié)構(gòu)特點(diǎn):
??1.單端面,橡膠波紋管補(bǔ)償,抗堵塞能力強(qiáng)。使用時(shí),不分彈簧旋向。
??2.輔助密封圈為丁腈橡膠、氟橡膠、乙丙橡膠、硅橡膠。
??3.符合ISO3069、DIN24960和GB6556標(biāo)準(zhǔn),通用性強(qiáng)。
??適用介質(zhì):
??油、水、酸、堿、鹽等清水及含有顆粒廢水、污水、污油中。
??工作參數(shù):
??固定物含量:≤10%
??溫 度:≤180℃
??壓 力:≤1.5MPa
??軸 徑:≤100mm
??材質(zhì)參數(shù):
??主體材質(zhì):304、316L或2205、2507、1.4529
??密封環(huán)材質(zhì):石墨、碳化硅、碳化鎢
??主要應(yīng)用:
??此型機(jī)械密封主要用于各類水泵、化工泵、污水泵、廢水泵、污油泵。
??常見型號(hào):
??KQW40/90-0.37/2 KQW40/100-0.55/2
??KQW40/110-0.75/2 KQW40/125-1.1/2
??KQW40/140-1.1/2 KQW40/150-1.5/2
??KQW40/160-2.2/2 KQW40/170-2.2/2
??KQW40/185-3/2 KQW40/200-4/2
??KQW40/220-4/2 KQW40/235-5.5/2
??KQW40/250-7.5/2 KQW50/90-0.75/2
??KQW50/100-1.1/2 KQW50/160-3/2
??KQW50/110-1.1/2 KQW50/125-1.5/2
??KQW50/140-1.5/2 KQW50/150-2.2/2
??KQW50/170-3/2 KQW50/185-4/2
??KQW50/200-5.5/2 KQW50/220-7.5/2
??KQW50/235-7.5/2 KQW65/125-3/2
??KQW50/250-11/2 KQW65/90-1.1/2
??KQW65/100-1.5/2 KQW65/110-2.2/2
??KQW65/140-3/2 KQW65/150-4/2
??KQW65/160-4/2 KQW65/170-5.5/2
??KQW65/185-7.5/2 KQW65/270-15/2
??KQW65/200-7.5/2 KQW65/220-11/2
??KQW65/235-11/2 KQW65/250-15/2
??KQW65/285-18.5/2 KQW65/300-22/2
??KQW65/315-30/2 KQW80/90-2.2/2
??KQW80/100-3/2 KQW80/160-7.5/2
??KQW80/110-4/2 KQW80/125-5.5/2
??KQW80/140-5.5/2 KQW80/150-7.5/2
??KQW80/170-7.5/2 KQW80/185-11/2
??KQW80/200-15/2 KQW80/220-15/2
??KQW80/235-18.5/2 KQW80/315-37/2
??KQW80/250-22/2 KQW80/270-22/2
??KQW80/285-30/2 KQW80/300-30/2
??KQW100/90-4/2 KQW100/100-5.5/2
??KQW100/110-7.5/2 KQW100/125-11/2
??KQW100/140-11/2 KQW100/200-22/2
??KQW100/150-11/2 KQW100/160-15/2
??KQW100/170-15/2 KQW100/185-18.5/2
??KQW100/220-30/2 KQW100/250-37/2
??KQW100/235-30/2 KQW100/270-37/2
??KQW100/285-45/2 KQW125/110-11/2
??KQW100/300-55/2 KQW100/315-75/2
??KQW125/90-7.5/2 KQW125/100-11/2
??KQW125/125-15/2 KQW125/140-15/2
??KQW125/150-18.5/2 KQW125/160-22/2
??KQW125/170-22/2 KQW125/250-55/2
??KQW125/185-30/2 KQW125/200-37/2
??KQW125/220-37/2 KQW125/235-45/2
??KQW125/270-55/2 KQW125/285-75/2
??KQW125/300-75/2 KQW125/315-90/2
??KQW125/320-15/4 KQW150/200-15/4
??KQW125/345-18.5/4 KQW125/370-22/4
??KQW125/400-30/4 KQW150/185-11/4
??KQW150/220-11/4 KQW150/235-15/4
??KQW150/250-18.5/4 KQW150/285-18.5/4
??KQW150/300-22/4 KQW150/400-45/4
??KQW150/315-30/4 KQW150/320-22/4
??KQW150/345-30/4 KQW150/370-37/4
??KQW150/410-55/4 KQW150/435-75/4
??KQW150/460-75/4 KQW200/185-15/4(Z)
??KQW200/200-18.5/4(Z) KQW200/300-37/4(Z)
??KQW200/220-15/4(Z) KQW200/235-18.5/4(Z)
??KQW200/250-30/4(Z) KQW200/285-30/4(Z)
??KQW200/315-45/4(Z) KQW200/320-37/4(Z)
??KQW200/345-45/4(Z) KQW200/370-55/4(Z)
??KQW200/400-75/4(Z) KQW250/250-45/4
??KQW200/410-75/4(Z) KQW200/435-90/4(Z)
??KQW200/460-110/4(Z) KQW250/235-37/4
??KQW250/300-55/4 KQW250/315-75/4
??KQW250/345-75/4 KQW250/370-90/4
??KQW250/400-110/4 KQW300/485-90/6
??KQW300/375-45/6 KQW300/410-55/6
??KQW300/425-55/6 KQW300/450-75/6
??KQW300-200A-45/4 KQW300-200-55/4
??KQW300-315B-55/4 KQW300-315A-75/4
??KQW300-315-90/4 KQW350-315B-110/4
??KQW300-400C-75/4 KQW300-400B-90/4
??KQW300-400A-110/4 KQW300-400-132/4
??KQW350-315A-132/4 KQW350-315B-90/4(Z)
??KQL40/90-0.37/2 KQL40/100-0.55/2
??KQL40/110-0.75/2 KQL40/125-1.1/2
??KQL40/140-1.1/2 KQL40/150-1.5/2
??KQL40/160-2.2/2 KQL40/170-2.2/2
??KQL40/185-3/2 KQL40/200-4/2
??KQL40/220-4/2 KQL40/235-5.5/2
??KQL40/250-7.5/2 KQL50/90-0.75/2
??KQL50/100-1.1/2 KQL50/160-3/2
??KQL50/110-1.1/2 KQL50/125-1.5/2
??KQL50/140-1.5/2 KQL50/150-2.2/2
??KQL50/170-3/2 KQL50/185-4/2
??KQL50/200-5.5/2 KQL50/220-7.5/2
??KQL50/235-7.5/2 KQL65/125-3/2
??KQL50/250-11/2 KQL65/90-1.1/2
??KQL65/100-1.5/2 KQL65/110-2.2/2
??KQL65/140-3/2 KQL65/150-4/2
??KQL65/160-4/2 KQL65/170-5.5/2
??KQL65/185-7.5/2 KQL65/270-15/2
??KQL65/200-7.5/2 KQL65/220-11/2
??KQL65/235-11/2 KQL65/250-15/2
??KQL65/285-18.5/2 KQL65/300-22/2
??KQL65/315-30/2 KQL80/90-2.2/2
??KQL80/100-3/2 KQL80/160-7.5/2
??KQL80/110-4/2 KQL80/125-5.5/2
??KQL80/140-5.5/2 KQL80/150-7.5/2
??KQL80/170-7.5/2 KQL80/185-11/2
??KQL80/200-15/2 KQL80/220-15/2
??KQL80/235-18.5/2 KQL80/315-37/2
??KQL80/250-22/2 KQL80/270-22/2
??KQL80/285-30/2 KQL80/300-30/2
??KQL100/90-4/2 KQL100/100-5.5/2
??KQL100/110-7.5/2 KQL100/125-11/2
??KQL100/140-11/2 KQL100/200-22/2
??KQL100/150-11/2 KQL100/160-15/2
??KQL100/170-15/2 KQL100/185-18.5/2
??KQL100/220-30/2 KQL100/250-37/2
??KQL100/235-30/2 KQL100/270-37/2
??KQL100/285-45/2 KQL125/110-11/2
??KQL100/300-55/2 KQL100/315-75/2
??KQL125/90-7.5/2 KQL125/100-11/2
??KQL125/125-15/2 KQL125/140-15/2
??KQL125/150-18.5/2 KQL125/160-22/2
??KQL125/170-22/2 KQL125/250-55/2
??KQL125/185-30/2 KQL125/200-37/2
??KQL125/220-37/2 KQL125/235-45/2
??KQL125/270-55/2 KQL125/285-75/2
??KQL125/300-75/2 KQL125/315-90/2
??KQL125/320-15/4 KQL150/200-15/4
??KQL125/345-18.5/4 KQL125/370-22/4
??KQL125/400-30/4 KQL150/185-11/4
??KQL150/220-11/4 KQL150/235-15/4
??KQL150/250-18.5/4 KQL150/285-18.5/4
??KQL150/300-22/4 KQL150/400-45/4
??KQL150/315-30/4 KQL150/320-22/4
??KQL150/345-30/4 KQL150/370-37/4
??KQL150/410-55/4 KQL150/435-75/4
??KQL150/460-75/4 KQL200/185-15/4(Z)
??KQL200/200-18.5/4(Z) KQL200/300-37/4(Z)
??KQL200/220-15/4(Z) KQL200/235-18.5/4(Z)
??KQL200/250-30/4(Z) KQL200/285-30/4(Z)
??KQL200/315-45/4(Z) KQL200/320-37/4(Z)
??KQL200/345-45/4(Z) KQL200/370-55/4(Z)
??KQL200/400-75/4(Z) KQL250/250-45/4
??KQL200/410-75/4(Z) KQL200/435-90/4(Z)
??KQL200/460-110/4(Z) KQL250/235-37/4
??KQL250/300-55/4 KQL250/315-75/4
??KQL250/345-75/4 KQL250/370-90/4
??KQL250/400-110/4 KQL300/485-90/6
??KQL300/375-45/6 KQL300/410-55/6
??KQL300/425-55/6 KQL300/450-75/6
??KQL300-200A-45/4 KQL300-200-55/4
??KQL300-315B-55/4 KQL300-315A-75/4
??KQL300-315-90/4 KQL350-315B-110/4
??KQL300-400C-75/4 KQL300-400B-90/4
??KQL300-400A-110/4 KQL300-400-132/4
??KQL350-315A-132/4 KQL350-315B-90/4(Z)
??注:由于泵用途較多,故密封材質(zhì)(摩擦副)也有不同,為保證密封的使用可靠性
??廠家推薦如下:
??1.清水(不含顆粒物工況)--動(dòng)環(huán)摩擦副選用(合金),靜環(huán)摩擦副選用(石墨)
??2.強(qiáng)腐蝕(含有顆粒物工況)--動(dòng)環(huán)摩擦副選用(碳化硅),靜環(huán)摩擦副選用(碳化硅)
??3.含有顆粒且振動(dòng)較大工況--動(dòng)環(huán)摩擦副選用(合金),靜環(huán)摩擦副選用(合金)
??4.也可以根據(jù)客戶要求定做。如沒有要求則默認(rèn)為(清水)
??安裝使用要求:
??1、設(shè)備轉(zhuǎn)軸的徑向跳動(dòng)應(yīng)不大于0.04毫米,軸向竄動(dòng)量不允許大于0.1毫米;
??2、設(shè)備的密封腔部位在安裝時(shí)應(yīng)保持清潔,密封零件應(yīng)進(jìn)行清洗,密封端面完好無損,防止雜質(zhì)和灰塵帶入密封部位;
??3、在安裝過程中嚴(yán)禁碰擊、敲打,以免使機(jī)械密封磨擦?xí)茡p而密封失效;
??4、安裝時(shí)在與密封相接觸的表面應(yīng)涂一層清潔的機(jī)械油,以便能順利安裝;
??5、安裝靜環(huán)壓蓋時(shí),擰緊螺絲必須受力均勻,保證靜環(huán)端面與軸心線的垂直要求;
??6、安裝后用手推動(dòng)動(dòng)環(huán),能使動(dòng)環(huán)在軸上靈活移動(dòng),并有一定彈性;
??7、安裝后用手盤動(dòng)轉(zhuǎn)軸,轉(zhuǎn)軸應(yīng)無輕重感覺;
??8、設(shè)備在運(yùn)轉(zhuǎn)前必須充滿介質(zhì),以防止干磨擦而使密封失效;
??適用范圍:化工泵、清水泵、污水泵、廢水泵、油泵
??適用行業(yè):煉鋼、造紙、化工、電力、水泥行業(yè)等
??適用主機(jī):上海凱泉泵業(yè)
??結(jié)構(gòu)特點(diǎn):
??1.單端面,橡膠波紋管補(bǔ)償,抗堵塞能力強(qiáng)。使用時(shí),不分彈簧旋向。
??2.輔助密封圈為丁腈橡膠、氟橡膠、乙丙橡膠、硅橡膠。
??3.符合ISO3069、DIN24960和GB6556標(biāo)準(zhǔn),通用性強(qiáng)。
??適用介質(zhì):
??油、水、酸、堿、鹽等清水及含有顆粒廢水、污水、污油中。
??工作參數(shù):
??固定物含量:≤10%
??溫 度:≤180℃
??壓 力:≤1.5MPa
??軸 徑:≤100mm
??材質(zhì)參數(shù):
??主體材質(zhì):304、316L或2205、2507、1.4529
??密封環(huán)材質(zhì):石墨、碳化硅、碳化鎢
??主要應(yīng)用:
??此型機(jī)械密封主要用于各類水泵、化工泵、污水泵、廢水泵、污油泵。
??常見型號(hào):
??KQW40/90-0.37/2 KQW40/100-0.55/2
??KQW40/110-0.75/2 KQW40/125-1.1/2
??KQW40/140-1.1/2 KQW40/150-1.5/2
??KQW40/160-2.2/2 KQW40/170-2.2/2
??KQW40/185-3/2 KQW40/200-4/2
??KQW40/220-4/2 KQW40/235-5.5/2
??KQW40/250-7.5/2 KQW50/90-0.75/2
??KQW50/100-1.1/2 KQW50/160-3/2
??KQW50/110-1.1/2 KQW50/125-1.5/2
??KQW50/140-1.5/2 KQW50/150-2.2/2
??KQW50/170-3/2 KQW50/185-4/2
??KQW50/200-5.5/2 KQW50/220-7.5/2
??KQW50/235-7.5/2 KQW65/125-3/2
??KQW50/250-11/2 KQW65/90-1.1/2
??KQW65/100-1.5/2 KQW65/110-2.2/2
??KQW65/140-3/2 KQW65/150-4/2
??KQW65/160-4/2 KQW65/170-5.5/2
??KQW65/185-7.5/2 KQW65/270-15/2
??KQW65/200-7.5/2 KQW65/220-11/2
??KQW65/235-11/2 KQW65/250-15/2
??KQW65/285-18.5/2 KQW65/300-22/2
??KQW65/315-30/2 KQW80/90-2.2/2
??KQW80/100-3/2 KQW80/160-7.5/2
??KQW80/110-4/2 KQW80/125-5.5/2
??KQW80/140-5.5/2 KQW80/150-7.5/2
??KQW80/170-7.5/2 KQW80/185-11/2
??KQW80/200-15/2 KQW80/220-15/2
??KQW80/235-18.5/2 KQW80/315-37/2
??KQW80/250-22/2 KQW80/270-22/2
??KQW80/285-30/2 KQW80/300-30/2
??KQW100/90-4/2 KQW100/100-5.5/2
??KQW100/110-7.5/2 KQW100/125-11/2
??KQW100/140-11/2 KQW100/200-22/2
??KQW100/150-11/2 KQW100/160-15/2
??KQW100/170-15/2 KQW100/185-18.5/2
??KQW100/220-30/2 KQW100/250-37/2
??KQW100/235-30/2 KQW100/270-37/2
??KQW100/285-45/2 KQW125/110-11/2
??KQW100/300-55/2 KQW100/315-75/2
??KQW125/90-7.5/2 KQW125/100-11/2
??KQW125/125-15/2 KQW125/140-15/2
??KQW125/150-18.5/2 KQW125/160-22/2
??KQW125/170-22/2 KQW125/250-55/2
??KQW125/185-30/2 KQW125/200-37/2
??KQW125/220-37/2 KQW125/235-45/2
??KQW125/270-55/2 KQW125/285-75/2
??KQW125/300-75/2 KQW125/315-90/2
??KQW125/320-15/4 KQW150/200-15/4
??KQW125/345-18.5/4 KQW125/370-22/4
??KQW125/400-30/4 KQW150/185-11/4
??KQW150/220-11/4 KQW150/235-15/4
??KQW150/250-18.5/4 KQW150/285-18.5/4
??KQW150/300-22/4 KQW150/400-45/4
??KQW150/315-30/4 KQW150/320-22/4
??KQW150/345-30/4 KQW150/370-37/4
??KQW150/410-55/4 KQW150/435-75/4
??KQW150/460-75/4 KQW200/185-15/4(Z)
??KQW200/200-18.5/4(Z) KQW200/300-37/4(Z)
??KQW200/220-15/4(Z) KQW200/235-18.5/4(Z)
??KQW200/250-30/4(Z) KQW200/285-30/4(Z)
??KQW200/315-45/4(Z) KQW200/320-37/4(Z)
??KQW200/345-45/4(Z) KQW200/370-55/4(Z)
??KQW200/400-75/4(Z) KQW250/250-45/4
??KQW200/410-75/4(Z) KQW200/435-90/4(Z)
??KQW200/460-110/4(Z) KQW250/235-37/4
??KQW250/300-55/4 KQW250/315-75/4
??KQW250/345-75/4 KQW250/370-90/4
??KQW250/400-110/4 KQW300/485-90/6
??KQW300/375-45/6 KQW300/410-55/6
??KQW300/425-55/6 KQW300/450-75/6
??KQW300-200A-45/4 KQW300-200-55/4
??KQW300-315B-55/4 KQW300-315A-75/4
??KQW300-315-90/4 KQW350-315B-110/4
??KQW300-400C-75/4 KQW300-400B-90/4
??KQW300-400A-110/4 KQW300-400-132/4
??KQW350-315A-132/4 KQW350-315B-90/4(Z)
??KQL40/90-0.37/2 KQL40/100-0.55/2
??KQL40/110-0.75/2 KQL40/125-1.1/2
??KQL40/140-1.1/2 KQL40/150-1.5/2
??KQL40/160-2.2/2 KQL40/170-2.2/2
??KQL40/185-3/2 KQL40/200-4/2
??KQL40/220-4/2 KQL40/235-5.5/2
??KQL40/250-7.5/2 KQL50/90-0.75/2
??KQL50/100-1.1/2 KQL50/160-3/2
??KQL50/110-1.1/2 KQL50/125-1.5/2
??KQL50/140-1.5/2 KQL50/150-2.2/2
??KQL50/170-3/2 KQL50/185-4/2
??KQL50/200-5.5/2 KQL50/220-7.5/2
??KQL50/235-7.5/2 KQL65/125-3/2
??KQL50/250-11/2 KQL65/90-1.1/2
??KQL65/100-1.5/2 KQL65/110-2.2/2
??KQL65/140-3/2 KQL65/150-4/2
??KQL65/160-4/2 KQL65/170-5.5/2
??KQL65/185-7.5/2 KQL65/270-15/2
??KQL65/200-7.5/2 KQL65/220-11/2
??KQL65/235-11/2 KQL65/250-15/2
??KQL65/285-18.5/2 KQL65/300-22/2
??KQL65/315-30/2 KQL80/90-2.2/2
??KQL80/100-3/2 KQL80/160-7.5/2
??KQL80/110-4/2 KQL80/125-5.5/2
??KQL80/140-5.5/2 KQL80/150-7.5/2
??KQL80/170-7.5/2 KQL80/185-11/2
??KQL80/200-15/2 KQL80/220-15/2
??KQL80/235-18.5/2 KQL80/315-37/2
??KQL80/250-22/2 KQL80/270-22/2
??KQL80/285-30/2 KQL80/300-30/2
??KQL100/90-4/2 KQL100/100-5.5/2
??KQL100/110-7.5/2 KQL100/125-11/2
??KQL100/140-11/2 KQL100/200-22/2
??KQL100/150-11/2 KQL100/160-15/2
??KQL100/170-15/2 KQL100/185-18.5/2
??KQL100/220-30/2 KQL100/250-37/2
??KQL100/235-30/2 KQL100/270-37/2
??KQL100/285-45/2 KQL125/110-11/2
??KQL100/300-55/2 KQL100/315-75/2
??KQL125/90-7.5/2 KQL125/100-11/2
??KQL125/125-15/2 KQL125/140-15/2
??KQL125/150-18.5/2 KQL125/160-22/2
??KQL125/170-22/2 KQL125/250-55/2
??KQL125/185-30/2 KQL125/200-37/2
??KQL125/220-37/2 KQL125/235-45/2
??KQL125/270-55/2 KQL125/285-75/2
??KQL125/300-75/2 KQL125/315-90/2
??KQL125/320-15/4 KQL150/200-15/4
??KQL125/345-18.5/4 KQL125/370-22/4
??KQL125/400-30/4 KQL150/185-11/4
??KQL150/220-11/4 KQL150/235-15/4
??KQL150/250-18.5/4 KQL150/285-18.5/4
??KQL150/300-22/4 KQL150/400-45/4
??KQL150/315-30/4 KQL150/320-22/4
??KQL150/345-30/4 KQL150/370-37/4
??KQL150/410-55/4 KQL150/435-75/4
??KQL150/460-75/4 KQL200/185-15/4(Z)
??KQL200/200-18.5/4(Z) KQL200/300-37/4(Z)
??KQL200/220-15/4(Z) KQL200/235-18.5/4(Z)
??KQL200/250-30/4(Z) KQL200/285-30/4(Z)
??KQL200/315-45/4(Z) KQL200/320-37/4(Z)
??KQL200/345-45/4(Z) KQL200/370-55/4(Z)
??KQL200/400-75/4(Z) KQL250/250-45/4
??KQL200/410-75/4(Z) KQL200/435-90/4(Z)
??KQL200/460-110/4(Z) KQL250/235-37/4
??KQL250/300-55/4 KQL250/315-75/4
??KQL250/345-75/4 KQL250/370-90/4
??KQL250/400-110/4 KQL300/485-90/6
??KQL300/375-45/6 KQL300/410-55/6
??KQL300/425-55/6 KQL300/450-75/6
??KQL300-200A-45/4 KQL300-200-55/4
??KQL300-315B-55/4 KQL300-315A-75/4
??KQL300-315-90/4 KQL350-315B-110/4
??KQL300-400C-75/4 KQL300-400B-90/4
??KQL300-400A-110/4 KQL300-400-132/4
??KQL350-315A-132/4 KQL350-315B-90/4(Z)
??注:由于泵用途較多,故密封材質(zhì)(摩擦副)也有不同,為保證密封的使用可靠性
??廠家推薦如下:
??1.清水(不含顆粒物工況)--動(dòng)環(huán)摩擦副選用(合金),靜環(huán)摩擦副選用(石墨)
??2.強(qiáng)腐蝕(含有顆粒物工況)--動(dòng)環(huán)摩擦副選用(碳化硅),靜環(huán)摩擦副選用(碳化硅)
??3.含有顆粒且振動(dòng)較大工況--動(dòng)環(huán)摩擦副選用(合金),靜環(huán)摩擦副選用(合金)
??4.也可以根據(jù)客戶要求定做。如沒有要求則默認(rèn)為(清水)
??安裝使用要求:
??1、設(shè)備轉(zhuǎn)軸的徑向跳動(dòng)應(yīng)不大于0.04毫米,軸向竄動(dòng)量不允許大于0.1毫米;
??2、設(shè)備的密封腔部位在安裝時(shí)應(yīng)保持清潔,密封零件應(yīng)進(jìn)行清洗,密封端面完好無損,防止雜質(zhì)和灰塵帶入密封部位;
??3、在安裝過程中嚴(yán)禁碰擊、敲打,以免使機(jī)械密封磨擦?xí)茡p而密封失效;
??4、安裝時(shí)在與密封相接觸的表面應(yīng)涂一層清潔的機(jī)械油,以便能順利安裝;
??5、安裝靜環(huán)壓蓋時(shí),擰緊螺絲必須受力均勻,保證靜環(huán)端面與軸心線的垂直要求;
??6、安裝后用手推動(dòng)動(dòng)環(huán),能使動(dòng)環(huán)在軸上靈活移動(dòng),并有一定彈性;
??7、安裝后用手盤動(dòng)轉(zhuǎn)軸,轉(zhuǎn)軸應(yīng)無輕重感覺;
??8、設(shè)備在運(yùn)轉(zhuǎn)前必須充滿介質(zhì),以防止干磨擦而使密封失效;