企业资质

福建速凌机械设备有限 公司

普通会员9
|
企业等级:普通会员
经营模式:
所在地区:福建 厦门
联系卖家:
手机号码:
公司官网:
企业地址:
企业概况

福建速凌机械设备有限公司位于厦门思明繁华的SM广场中心地带是全国工业传动流体自动化领域实力较强的经销商,有着丰富的气动液压技术服务、工业销售及国际采购的经验,主营产品涉及液压泵阀(电磁阀、柱塞泵拳头产品)、工控产品、驱动模块、伺服电机、可编程控制器PLC、数控传动、传感器系列、电源、气动元件、工业仪......

8941000302插头现货***

产品编号:234314697                    更新时间:2018-11-27
价格: ¥1.00

福建速凌机械设备有限 公司

  • 主营业务:液压元件
  • 公司官网:
  • 公司地址:

联系人名片:

联系时务必告知是在"产品网"看到的

产品详情
安沃驰***ENTICS精密调压阀
3610628300
3610628400
3610628500
3610628600
3610628700
3610628330
3610628630
安沃驰***ENTICS精密调压阀
3610647100
3610647400
3610647500
3610647600
溢流阀
安全阀
安沃驰***ENTICS安全阀,系列RV1
R412007521
R412007522
R412007523
R412007524
R412007525
R412007526
R412007527
R412007528
R412007529
R412007530
R412007531
R412007532
R412007533
R412007534
R412007535
R412007721
R412007536
R412007537
R412007538
R412007539
R412007540
R412007541
R412007542
R412007720
R412007690
R412007691
R412007692
R412007699
R412007696
R412007702
R412007698
R412007697
R412007693
R412007694
R412007700
R412007701
R412007695
R412007703
R412007543
R412007544
R412007684
R412007545
R412007546
R412007547
R412007548
R412007549
R412007550
R412007551
R412007552
安沃驰***ENTICS安全阀,系列RV2
R412007567
R412007722
R412007704
R412007558
R412007561
R412007563
十一、抓取和真空技术
非接触输送系统
系列NCT
安沃驰***ENTICS非接触输送系统,系列NCT-AL
R412010372
R412010373
R412010374
R412010375
R412010640
安沃驰***ENTICS非接触输送系统,系列NCT-PK
R412014866
R412014867
R412014868
R412014869
压力传感器
系列PE2
安沃驰***ENTICS压力传感器,系列PE2
R412010848
R412010849
R412010853
R412010856
R412010850
R412010851
R412010854
R412010855
R412010857
R412010858

***ENTICS截止阀0821003075

 

 

安装方法

一、旋启式止回阀:旋启式止回阀的阀瓣呈圆盘状,绕阀座通道的转轴作旋转运动,因阀内通道成流线型,流动阻力比升降式止回阀小,适用于低流速和流动不常变化的大口径场合,但不宜用于脉动流,其密封性能不及升降式。旋启式止回阀分单瓣式、双瓣式和多半式三种,这三种形式主要按阀门口径来分,目的是为了防止介质停止流动或倒流时,减弱水力冲击。

二、升降式止回阀:阀瓣沿着阀体垂直中心线滑动的止回阀,升降式止回阀只能安装在水平管道上,在高压小口径止回阀上阀瓣可采用圆球。升降式止回阀的阀体形状与截止阀一样(可与截止阀通用),因此它的流体阻力系数较大。其结构与截止阀相似,阀体和阀瓣与截止阀相同。阀瓣上部和阀盖下部加工有导向套简,阀瓣导向简可在阀盏导向简内自由升降,当介质顺流时,阀瓣靠介质推力开启,当介质停流时,阀瓣靠自垂降落在阀座上,起阻止介质逆流作用。直通式升降止回阀介质进出口通道方向与阀座通道方向垂直;立式升降式止回阀,其介质进出口通道方向与阀座通道方向相同,其流动阻力较直通式小。

三、碟式止回阀:阀瓣围绕阀座内的销轴旋转的止回阀。碟式止回阀结构简单,只能安装在水平管道上,密封性较差。

四、管道式止回阀:阀瓣沿着阀体中心线滑动的阀门。管道式止回阀是新出现的一种阀门,它的体积小,重量较轻,加工工艺性好,是止回阀发展方向之一。但流体阻力系数比旋启式止回阀略大。

五、压紧式止回阀:这种阀门是做为锅炉给水和蒸汽切断用阀,它具有升降式止回阀和截止阀或角阀的综合机能。

此外,还有些不适用于泵出口安装的止回阀,如底阀、弹簧式,Y型等。

***ENTICS截止阀0821003075

0821003075 SHUT-OFF VALVE G1/8
0821003076 SHUT-OFF VALVE G1/4
0821100003 PRESSURE SWITCH .
0821100018 PRESSURE SWITCH .
0821100020 PM1-M3-F001-V09-000-DINA
0821100066 PE3-PV-G018-V10-000-M008-( ANALOG 1-5V)
0821100067 PE3-PV-G018-V10-100-M008-( ANALOG 1-5V)
0821100069 PE3-P2-G018-V10-000-M008
0821100070 PE3-P2-G018-000-100-M008
0821100094 PE2-P1-G014-000-400-M012
0821100107 PE2-P2-G014-000-160-M012
0821100110 PE2-PA-F001-V10-010-M012
0821200003 THROTTLE CHECK VLV G1/2
0821200005 THROTTLE CHECK VLV NG4 (G1/4) D.4,0
0821200008 THROTTLE CHECK VLV NG4 (G1/8) D.2,0
0821200009 THROTTLE CHECK VLV G1/8 D.1,0
0821200010 ERU G1/8 NPTF 1
0821200011 THROTTLE CHECK VLV .
0821200013 THROTTLE CHECK VLV .
0821200014 E.R.U..G 3/8
0821200015 E.R.U..G 3/4
0821200016 E.R.U..G 1
0821200117 THROTTLE CHECK VLV .
0821200118 THROTTLE CHECK VLV .
0821200128 THROTTLE CHECK VLV .
0821200129 RACCORD-BANJO-ETRANGL-SORTIE-M5-6-CC02
0821200149 THROTTLE CHECK VLV .
0821200175 THROTTLE CHECK VLV .
0821200176 THROTTLE CHECK VLV .
0821200177 THROTTLE CHECK VLV .
0821200178 THROTTLE CHECK VLV .
0821200179 THROTTLE CHECK VLV .
0821200180 THROTTLE CHECK VLV .
0821200181 THROTTLE CHECK VLV .
0821200182 THROTTLE CHECK VLV .
0821200183 THROTTLE CHECK VLV .
0821200184 THROTTLE CHECK VLV .
0821200185 THROTTLE CHECK VLV .
0821200192 THROTTLE CHECK VLV DROSSELRUECKSCHLAGV
0821200194 THROTTLE CHECK VLV NG4 G1/8
0821200196 THROTTLE CHECK VLV .
0821200200 THROTTLE CHECK VLV .
0821200201 THROTTLE CHECK VLV RV M.INNENG. G1/8
0821200202 THROTTLE CHECK VLV .
0821200203 THROTTLE CHECK VLV DROSSELRUECKSCHLAGVE
0821200204 THROTTLE CHECK VLV NG4 (G1/8)
0821200205 THROTTLE CHECK VLV G1/4
0821200206 THROTTLE CHECK VLV NG8 (G3/8)
0821200207 THROTTLE CHECK VLV G1/2
0821200208 THROTTLE CHECK VLV .
0821200209 THROTTLE CHECK VLV .
0821200210 THROTTLE CHECK VLV .
0821200211 THROTTLE CHECK VLV G1/4
0821200212 THROTTLE CHECK VLV .
0821200213 THROTTLE CHECK VLV G1/4
0821200214 THROTTLE CHECK VLV DROSSELRUECKSCHLAGVE
0821200215 THROTTLE CHECK VLV G1/8
0821200216 THROTTLE CHECK VLV .
0821200217 THROTTLE CHECK VLV ROSSELVENTIL 3/8
0821200225 THROTTLE CHECK VLV .
0821200226 THROTTLE CHECK VLV .
0821200227 THROTTLE CHECK VLV .
0821200229 THROTTLE CHECK VLV .
0821200230 THROTTLE CHECK VLV .
0821200231 THROTTLE CHECK VLV .
0821200232 THROTTLE CHECK VLV .
0821200234 THROTTLE CHECK VLV .
0821200236 THROTTLE CHECK VLV ADMISSION-G1/8-D6
0821200237 THROTTLE CHECK VLV .
0821200238 THROTTLE CHECK VLV ADMISSION-G1/4-D6
0821200239 THROTTLE CHECK VLV .
0821200241 THROTTLE CHECK VLV .
0821200242 THROTTLE CHECK VLV ROSSELRUECKSCHLAGV.
0821200243 THROTTLE CHECK VLV .
0821200244 THROTTLE CHECK VLV ROSSELRUECKSCHLAGV.
0821200245 THROTTLE CHECK VLV .
0821200246 THROTTLE CHECK VLV ROSSELRUECKSCHLAGVE
0821200247 THROTTLE CHECK VLV ROSSELRUECKSCHLAGV.
0821200248 THROTTLE CHECK VLV ROSSELRUECKSCHLAGVE
0821200249 THROTTLE CHECK VLV .
0821200253 DROSSELRUECKSCHLAGVENTIL G014
0821201001 THROTTLE VALVE DROSSEL
0821201002 THROT. SCREW INS. .
0821201003 THROT. SCREW INS. DROSSEL
0821201004 THROTTLE VALVE NG4 (G1/8) LIM D?B 2
0821201006 THROTTLE VALVE LIMITEUR DE DEBIT 8
0821201007 THROTTLE VALVE .
0821201008 THROT. SCREW INS. .
0821201009 THROT. SCREW INS. .
0821201010 THROTTLE VALVE LIMITEUR DE DEBIT 1
0821201011 THROTTLE VALVE NG6 (G1/4)LIM DEBIT 4
0821201022 THROTTLE VALVE DROSSELPL.ZUR ABLUFT
0821201023 THROTTLE VALVE ROSSELPL.ZUR ABLUFTD
0821201024 THROTTLE VALVE DROSSELPL.ZUR ABLUFT
0821201025 THROTTLE VALVE .
0821201101 THROT. SCREW INS. DROSSELVENTIL M. SCH
0821201102 THROT. SCREW INS. NG4-G1/8
0821201103 THROT. SCREW INS. G014
0821201104 THROT. SCREW INS. G3/8
0821201105 THROT. SCREW INS. NG12 (G1/2)
0821201106 THROT. SCREW INS. .
0821201109 THROTTLE VALVE .
0821300007 NLC2-FRL-R012-GAU-100-PNB-MA-40,00
0821300008 MAINTENANCE UNIT F.R.L.T4............
0821300014 NL2-FRL-R014-GAU-100-PNB-MA-40,00
0821300030 NLC-FRL-G014-GAU-100-PNB-MA-40,00
0821300032 NLC-FRL-G038-GAU-100-PNB-MA-40,00
0821300033 NL2-FRL-G038-GAU-100-PNB-AO-40,00
0821300040 NLC-FRL-G012-GAU-100-PNB-MA-40,00
0821300042 NL4-FRL-G034-GAU-100-PNB-MA-40,00
0821300050 NLC-FRL-G014-GAU-100-PBS-MA-40,00
0821300052 NLC-FRL-G038-GAU-100-PBS-MA-40,00
0821300060 NL4-FRL-G012-GAU-100-PBS-MA-40,00
0821300062 NLC-FRL-G034-GAU-100-PBS-MA-40,00
0821300088 NL4-DIO-G012-N***
0821300089 NL4-DIO-G038-N***
0821300105 CONTROL BLOCK .
0821300106 CONTROL BLOCK .
0821300112 MAINTENANCE UNIT .
0821300117 MAINTENANCE UNIT NL2, G1/4, D=40
0821300118 MAINTENANCE UNIT .
0821300132 MAINTENANCE UNIT .
0821300141 SHUT-OFF VALVE .
0821300204 MAINTENANCE UNIT .
0821300206 MAINTENANCE UNIT .
0821300212 NL4-FRE-G012-GAU-3 5MU-PBS-HO
0821300220 NL2-FRE-G014-GAU-100-PBS-HO-05,00
0821300221 NL2-FRE-G014-GAU-100-SSS-HO-05,00
0821300222 NL2-FRE-G014-GAU-100-PBS-AO-05,00
0821300223 NL2-FRE-G014-GAU-100-SSS-AO-05,00
0821300224 NL2-FRE-G038-GAU-010-PBP-HO-05,00
0821300226 NL2-FRE-G038-GAU-010-PNB-AO-05,00
0821300228 NL2-FRE-G038-GAU-100-SSS-AO-05,00
0821300234 NL4-FRE-G012-GAU-100-PBS-HO-05,00
0821300235 NL4-FRE-G012-GAU-100-SSS-HO-05,00
0821300236 NL4-FRE-G012-GAU-100-PBS-AO-05,00-2
0821300237 NL4-FRE-G012-GAU-100-PBS-AO-05,00
0821300238 NL4-FRE-G012-GAU-100-SSS-AO-05,00
0821300239 NL4-FRE-G034-GAU-100-PBS-HO-05,00
0821300240 NL4-FRE-G034-GAU-100-SSS-HO-05,00
0821300241 NL4-FRE-G034-GAU-100-PNB-AO-05,00
0821300243 NL4-FRE-G034-GAU-100-SSS-AO-05,00
0821300245 NON-RETURN VALVE .
0821300247 NL2-FRE-N014
0821300250 CONTROL BLOCK VANNE REMISE PRESSIO
0821300252 DIR.-CONTROL VALVE 3/2 WEGV. G1/4 NL2
0821300253 NL2-FRE-G014-GAN-040-PNB-HO-05,00
0821300255 NL2-ACC-G014
0821300258 NL2-FRE-G014-GAU-100-PNB-HO-05,00-SONDER
0821300260 MAINTENANCE UNIT .
0821300264 BRANCH PIECE NL2-DIC-G014-NC2
0821300265 MAINTENANCE UNIT .
0821300266 CONTROL BLOCK ELEKT VORRANGSTEUERG
0821300267 CONTROL BLOCK 4
0821300268 CHARGING DEVICE .
0821300271 CONTROL BLOCK .
0821300275 NL2-FRE-G014-GAN-010-SSS-HO-05,00
0821300277 CONTROL BLOCK .
0821300281 NL4-FRE-G012-GAN 40MU-SSS-AO
0821300285 NL4-FRE-G012-GAU-100-PNB-AO-05,00-SONDER
0821300288 NL4-FRE-G012-GAU-100-PBS-HO-05,00-SONDER
0821300299 CONTROL BLOCK .
0821300300 NL2-FRE-G014-GAU-100-PNB-HO-05,00
0821300301 NL2-FRE-G014-GAU-100-PBS-HO-05,00
0821300302 NL2-FRE-G014-GAU-100-SSS-HO-05,00
0821300303 NL2-FRE-G014-GAU-100-PNB-AO-05,00
0821300304 NL2-FRE-G014-GAU-100-PBS-AO-05,00
0821300305 NL2-FRE-G014-GAU-100-SSS-AO-05,00
0821300306 NL2-FRE-G014-GAU-100-PNB-HO-05,00
0821300307 NL2-FRE-G014-GAU-030-PNB-HO-05,00
0821300308 NL2-FRE-G014-GAU-060-PNB-HO-05,00
0821300310 NL2-FRE-G014-GAU-100-PNB-HO-05,00-SONDER
0821300312 NL2-FRE-G014-GAU-100-PNB-AO-05,00
0821300316 NL2-FRE-G014-GAN-100-PNB-HO-05,00
0821300330 NL2-FRE-G038-GAU-100-PNB-HO-05,00
0821300331 NL2-FRE-G038-GAU-100-PBS-HO-05,00
0821300332 NL2-FRE-G038-GAU-100-SSS-HO-05,00
0821300333 NL2-FRE-G038-GAU-100-PNB-AO-05,00
0821300334 NL2-FRE-G038-GAU-100-PBS-AO-05,00
0821300335 NL2-FRE-G038-GAU-100-SSS-AO-05,00
0821300336 NL2-FRE-G038-GAU-100-PNB-HO-05,00
0821300338 NL2-FRE-G018-GAN-100-PNB-HO-40,00-SONDER
0821300341 NL2-FRE-G038-GAU-100-PNB-HO-05,00-MODI &
0821300342 NL2-FRE-G038-GAU-100-PNB-AO-05,00-MODI &
0821300343 NL2-FRE-G038-GAN-100-PNB-HO-05,00
0821300344 NL2-FRE-G038-GAU-100-PNB-AO-05,00-E11
0821300345 NL2-FRE-G014-GAU-100-PNB-AO-05,00
0821300347 NL2-FRE-G014-GAN-100-PNB-AO-05,00
0821300349 NL2-FRE-G014-GAU-060-PNB-AO-05,00
0821300350 NL4-FRE-G012-GAU-100-PNB-HO-05,00
0821300351 NL4-FRE-G012-GAU-100-PBS-HO-05,00
0821300352 NL4-FRE-G012-GAU-100-SSS-HO-05,00
0821300353 NL4-FRE-G012-GAU-100-PNB-AO-05,00
0821300354 NL4-FRE-G012-GAU-100-PBS-AO-05,00
0821300355 NL4-FRE-G012-GAU-100-SSS-AO-05,00
0821300356 NL4-FRE-G012-GAU-100-PNB-HO-05,00
0821300358 NL4-FRE-G012-GAU-060-PNB-AO-05,00
0821300361 NL4-FRE-G012-GAU-060-SSS-AO-05,00
0821300362 NL4-FRE-G012-GAU-030-PNB-HO-05,00
0821300364 NL4-FRE-G012-GAN-100-PNB-HO-05,00
0821300366 NL4-FRE-G012-GAU-060-SSS-AO-05,00-SONDER
0821300367 NL4-FRE-G012-GAN-100-PNB-AO-05,00
0821300368 NL4-FRE-G012-GAU-100-PNB-HO-05,00-SONDER
0821300369 NL4-FRE-G012-GAU-100-PNB-HO-05,00-SONDER
0821300372 NL4-FRE-G038-GAU-100-SSS-HO-05,00
0821300380 NL4-FRE-G034-GAU-100-PNB-HO-05,00
0821300381 NL4-FRE-G034-GAU-100-PBS-HO-05,00
0821300382 NL4-FRE-G034-GAU-100-SSS-HO-05,00
0821300383 NL4-FRE-G034-GAU-100-PNB-AO-05,00
0821300384 NL4-FRE-G034-GAU-100-PBS-AO-05,00
0821300385 NL4-FRE-G034-GAU-100-SSS-AO-05,00
0821300386 NL4-FRE-G034-GAU-100-PNB-HO-05,00
0821300392 NL4-FRE-G012-GAU-060-PNB-HO-05,00
0821300393 NL4-FRE-G012-GAU-060-PBS-AO-05,00-SONDER
0821300394 NL4-FRE-G012-GAU-160-SSS-HO-05,00
0821300396 NL4-FRE-G012-GAN-060-PBS-AO-05,00-E11
0821300400 NL2-ACD-G014-GAU-100-PNB-HO-05,00
0821300401 NL2-ACD-G014-GAU-100-PBS-HO-05,00
0821300402 NL2-ACD-G014-GAU-100-SSS-HO-05,00
0821300403 NL2-ACD-G014-GAU-100-PNB-AO-05,00
0821300404 NL2-ACD-G014-GAU-100-PBS-AO-05,00
0821300405 NL2-ACD-G014-GAU-100-SSS-AO-05,00
0821300410 PR1-FRE-G014-GAN-020-SSN-MA-10,00
0821300411 PR1-FRE-G014-GAN-050-SSN-MA-10,00
0821300427 MAINTENANCE UNIT .
0821300429 MAINTENANCE UNIT .
0821300430 NL2-ACD-G038-GAU-100-PNB-HO-05,00
0821300431 NL2-ACD-G038-GAU-100-PBS-HO-05,00
0821300432 NL2-ACD-G038-GAU-100-SSS-HO-05,00
0821300433 NL2-ACD-G038-GAU-100-PNB-AO-05,00
0821300434 NL2-ACD-G038-GAU-100-PBS-AO-05,00
0821300435 NL2-ACD-G038-GAU-100-SSS-AO-05,00
0821300441 MAINTENANCE UNIT .
0821300442 MAINTENANCE UNIT .
0821300446 MAINTENANCE UNIT .
0821300450 NL2-ACT-G014-GAU-100-PNB-HO-05,00
0821300451 NL2-ACT-G014-GAU-100-PBS-HO-05,00
0821300452 NL2-ACT-G014-GAU-100-SSS-HO-05,00
0821300453 NL2-ACT-G014-GAU-100-PNB-AO-05,00
0821300454 NL2-ACT-G014-GAU-100-PBS-AO-05,00
0821300455 NL2-ACT-G014-GAU-100-SSS-AO-05,00
0821300478 MAINTENANCE UNIT .
0821300480 NL2-ACT-G038-GAU-100-PNB-HO-05,00
0821300481 NL2-ACT-G038-GAU-100-PBS-HO-05,00
0821300482 NL2-ACT-G038-GAU-100-SSS-HO-05,00
0821300483 NL2-ACT-G038-GAU-100-PNB-AO-05,00
0821300484 NL2-ACT-G038-GAU-100-PBS-AO-05,00
0821300485 NL2-ACT-G038-GAU-100-SSS-AO-05,00
0821300500 NL4-ACD-G012-GAU-100-PNB-HO-05,00-ON
0821300501 NL4-ACD-G012-GAU-100-PBS-HO-05,00-ON
0821300502 NL4-ACD-G012-GAU-100-SSS-HO-05,00-ON
0821300503 NL4-ACD-G012-GAU-100-PNB-AO-05,00-ON
0821300504 NL4-ACD-G012-GAU-100-PBS-AO-05,00-ON
0821300505 NL4-ACD-G012-GAU-100-SSS-AO-05,00-ON
0821300512 MAINTENANCE UNIT .
0821300514 MAINTENANCE UNIT .
0821300515 MAINTENANCE UNIT .
0821300516 MAINTENANCE UNIT .
0821300518 MAINTENANCE UNIT .
0821300530 NL4-ACD-G034-GAU-100-PNB-HO-05,00-ON
0821300531 NL4-ACD-G034-GAU-100-PBS-HO-05,00-ON
0821300532 NL4-ACD-G034-GAU-100-SSS-HO-05,00-ON
0821300533 NL4-ACD-G034-GAU-100-PNB-AO-05,00-ON
0821300534 NL4-ACD-G034-GAU-100-PBS-AO-05,00-ON
0821300535 NL4-ACD-G034-GAU-100-SSS-AO-05,00-ON
0821300550 NL4-ACT-G012-GAU-100-PNB-HO-05,00-ON
0821300551 NL4-ACT-G012-GAU-100-PBS-HO-05,00-ON
0821300552 NL4-ACT-G012-GAU-100-SSS-HO-05,00-ON
0821300553 NL4-ACT-G012-GAU-100-PNB-AO-05,00-ON
0821300554 NL4-ACT-G012-GAU-100-PBS-AO-05,00-ON
0821300555 NL4-ACT-G012-GAU-100-SSS-AO-05,00-ON
0821300557 MAINTENANCE UNIT .
0821300579 MAINTENANCE UNIT .
0821300580 NL4-ACT-G034-GAU-100-PNB-HO-05,00-ON
0821300581 NL4-ACT-G034-GAU-100-PBS-HO-05,00-ON
0821300582 NL4-ACT-G034-GAU-100-SSS-HO-05,00-ON
0821300583 NL4-ACT-G034-GAU-100-PNB-AO-05,00-ON
0821300584 NL4-ACT-G034-GAU-100-PBS-AO-05,00-ON
0821300585 NL4-ACT-G034-GAU-100-SSS-AO-05,00-ON
0821300660 PRESSURE REGULATOR .
0821300661 PRESSURE REGULATOR .
0821300662 PRESSURE REGULATOR .
0821300663 NL1-RGS-G018-GAH-MAN-030-SS
0821300664 NL1-RGS-G018-GAH-MAN-060-SS
0821300665 NL1-RGS-G018-GAH-MAN-100-SS
0821300666 NL1-RGS-G014-GAH-MAN-030-SS
0821300667 NL1-RGS-G014-GAH-MAN-060-SS
0821300668 NL1-RGS-G014-GAH-MAN-100-SS
0821300673 NL1-SOV-G014-SOE-024-DS
0821300675 NL1-SOV-G014-SOE-CON-DS
0821300676 NL1-SOV-G014-SOE-CON-DS
0821300703 PRESSURE REGULATOR .

福建速凌机械设备有限 公司电话:传真:联系人:

地址:主营产品:液压元件

Copyright © 2026 版权所有: 产品网店铺主体:福建速凌机械设备有限 公司

免责声明:以上所展示的信息由企业自行提供,内容的真实性、准确性和合法性由发布企业负责。产品网对此不承担任何保证责任。