液壓連接-五種管接頭系統(tǒng)

1、液壓連接-五種管接頭系統(tǒng)目前有五種管接頭系統(tǒng)通常用於液壓連接，這五種管接頭系統(tǒng)按地理位置或按國(guó)家劃分為：北美標(biāo)準(zhǔn)NPTF說明：這是一種乾密封螺紋；是用於輸送燃油的國(guó)內(nèi)錐管螺紋，既可用於外螺紋端接頭，也可用於內(nèi)螺紋端接頭。NPTF 外螺紋可與NPTF、NPSF或NPSM內(nèi)螺紋配合。NPTF管接頭與BSPT管接頭類似但不可互相換，大多數(shù)尺寸螺紋的螺距不同併且牙型角是60°，而BSPT螺紋的牙型角是55°。 JIC37°錐角內(nèi)螺紋接頭說明：37°錐角（JIC）汽車工程師協(xié)會(huì)（SAE）規(guī)定37°錐角或錐座可用於高壓液壓管路。這類管接頭通常稱為JIC管接

2、頭。 JIC外螺紋是直紋只能和JIC內(nèi)螺紋配合，JIC外螺紋是直螺紋，並具有37°錐座面，JIC內(nèi)螺紋也是直螺紋，並具有37°錐座面。其密封在37°錐座面處形成，某些尺寸的螺紋與SAE45°錐角螺紋相同，應(yīng)仔細(xì)測(cè)量錐角以進(jìn)行區(qū)分。 SAE 45°錐角外螺紋接頭說明：SAE（45°錐角）這是用於具有45°錐角或錐座的管接頭的術(shù)語(yǔ)。軟銅管通常採(cǎi)用這種接頭，因?yàn)樵摬牧弦嘴都庸こ?5°角。這種管接頭適用於低壓應(yīng)用場(chǎng)合-例如用於燃油管路和制冷管路。SAE 45°錐角外螺紋只能和SAE 45°錐角內(nèi)螺紋配合

3、。SAE外螺紋是直螺紋並具有45°錐座面。而SAE內(nèi)螺紋也是直螺紋，並具有45°錐座面。其密封在45°錐座面處形成。某些尺寸的螺紋與SEA 37°錐角螺紋相同。應(yīng)仔細(xì)測(cè)量錐角以進(jìn)行區(qū)行。O形圈端面密封外螺紋接頭說明： O形圈端密封外螺紋只能和O形圈端面密封內(nèi)螺紋配合，外螺紋是直螺紋帶O形圈；內(nèi)螺紋是直螺紋帶密封端面，外螺紋在O形圈處密封，而內(nèi)螺紋在密封端面處密封。 O形圏法蘭SAE J518 說明：SAE J518SAE 61型和62型四螺栓分離式法蘭通常在世界範(fàn)圍內(nèi)廣泛應(yīng)用於連接泵與馬達(dá)。此處有三種例外情況； 1. 倍乘系數(shù)-10，不是SAE標(biāo)準(zhǔn)尺寸，

4、但在北美以外地區(qū)卻應(yīng)用很普遍 2. 卡特彼勒式法蘭，具有一個(gè)較厚的法蘭頭（表中尺寸C），其外徑與SAE 62型法蘭外徑一樣大。 3. Poclain法蘭，其與SAE法蘭根本不同。 公稱法蘭尺寸61型（FL）62型（FL）卡特彼勒式（FLC）法蘭外徑ABC法蘭外徑ABC法蘭外徑ABC1/21.188 0.688 1.500 0.265 1.250 0.718 1.594 0.305 5/81.3380.265 3/41.500 0.875 1.875 0.265 1.625 0.937 2.000 0.345 1.625 0.938 2.000 0.560 11.750 1.031 2.0620

5、.315 1.875 1.093 2.250 0.375 1.875 1.094 2.250 0.560 1 1/4 2.0001.188 2.3120.315 2.125 1.250 2.625 0.405 2.215 1.250 2.625 0.560 1 1/2 2.3751.406 2.7500.315 2.500 1.473 3.125 0.495 2.500 1.438 3.125 0.560 2 2.8121.688 3.062 0.375 3.125 1.750 3.812 0.495 3.125 1.750 3.812 0.560 2 1/2 3.3122.000 3.500

6、 0.375 3 4.0002.438 4.188 0.375 3 1/2 4.500 2.750 4.750 0.422 4 5.000 3.062 5.125 0.422 5 6.000 3.625 6.000 0.422 O形圈平面密封固定型外螺紋接頭說明：當(dāng)外螺紋接頭上O形圈與內(nèi)螺紋接頭上的平面接觸時(shí)形成密封，在液壓系統(tǒng)可以使用彈性體密封來(lái)控制洩漏，並且在防洩漏功能極為重要的情況下，可採(cǎi)用這一類管接頭。 壓套式管接頭說明：壓套式固定型外螺紋接頭只能與壓套式內(nèi)螺紋螺母及壓套配合。外螺紋接頭是直螺紋帶24°錐座。內(nèi)螺紋頭是直螺紋並帶有作為密封面的壓套。其密封在壓套與外螺紋接頭的2

7、4°錐座之間、壓套與內(nèi)螺紋接頭的內(nèi)管之間形成。英國(guó)標(biāo)準(zhǔn)SAE倒錐面接頭認(rèn)為所有國(guó)外螺紋均為公制的，這是一個(gè)誤解。通常不是這樣，有兩種常用的螺紋形式-公制螺紋和惠氏標(biāo)準(zhǔn)螺紋（BSP）。英國(guó)標(biāo)準(zhǔn)直管（BSP）螺紋，也叫惠氏標(biāo)準(zhǔn)螺紋。它既可以是直螺紋（BSPP），也可以是錐螺紋（BSPT），均帶有倒錐面。其法蘭與SAE61型或62型法蘭類似（-10*除外）。端口連接通常通過BSPP螺紋。其密封採(cǎi)用軟金屬密封環(huán)。BSPP（直）外螺紋可以與BSPP（直）內(nèi)螺紋或內(nèi)螺紋端口配合。BSPP外螺紋是直螺紋並帶30°錐座。BSPP內(nèi)螺紋也是直螺紋並帶30°錐座。內(nèi)螺紋端口是直螺紋並

8、帶密封端面。端口處的密封通過外螺紋接頭上的O形圏或軟金屬墊圏形成。BSPP（直螺紋）接頭與NPSM接頭類似但不可互換。其大多數(shù)尺寸螺紋的螺距不同，螺紋牙型角是55°，而NPSM螺紋牙型角是60°（-10是非SAE規(guī)格的法蘭）英國(guó)標(biāo)準(zhǔn)直管螺紋(BSP) 說明：英國(guó)標(biāo)準(zhǔn)直管（BSP）螺紋，也叫惠氏標(biāo)準(zhǔn)螺紋。它既可以是直螺紋（BSPP），也可以是錐螺紋（BSPT），均帶有倒錐面。其法蘭與SAE61型或62型法蘭類似（-10*除外）。端口連接通常通過BSPP螺紋。其密封採(cǎi)用軟金屬密封環(huán)。BSPP（直）外螺紋可以與BSPP（直）內(nèi)螺紋或內(nèi)螺紋端口配合。BSPP外螺紋是直螺紋並帶30&

9、#176;錐座。BSPP內(nèi)螺紋也是直螺紋並帶30°錐座。內(nèi)螺紋端口是直螺紋並帶密封端面。端口處的密封通過外螺紋接頭上的O形圏或軟金屬墊圏形成。BSPP（直螺紋）接頭與NPSM接頭類似但不可互換。其大多數(shù)尺寸螺紋的螺距不同，螺紋牙型角是55°，而NPSM螺紋牙型角是60°（-10是非SAE規(guī)格的法蘭）英國(guó)標(biāo)準(zhǔn)錐管螺紋(BSPT)說明：BSPT（錐）外螺紋可以與BSPT（錐）內(nèi)螺紋或BSPP（直）內(nèi)螺紋配合。BSPT外螺紋是錐螺紋。當(dāng)其與BSPT（錐）內(nèi)螺紋或BSPP（直）內(nèi)螺紋端口配合時(shí)，在螺紋處形成密封。BSPT接頭與NPTF接頭近似但不可互換。其大多數(shù)螺紋的螺距

10、不同，螺紋牙型角為55°，而NPSM螺紋牙型角是60°法國(guó)標(biāo)準(zhǔn)法國(guó)GAZ是常用的管接頭。這種接頭是公制螺紋並帶24°錐座。與德國(guó)DIN管接頭類似，但其螺紋在些尺寸上有所不同。雖然二者都是公制螺紋，但是法國(guó)所有規(guī)格的管接頭均採(cǎi)用細(xì)牙螺紋，而德國(guó)DIN管接頭尺寸較大，採(cǎi)用粗牙螺紋。大多數(shù)端口連接均為法蘭連接。法國(guó)標(biāo)準(zhǔn)法蘭與SAE和hellip標(biāo)準(zhǔn)法蘭不同；其法蘭端面有一個(gè)突起的凸臺(tái)。這種法蘭叫作Poclain型法蘭。 1 GAZ24°2 GAZ Poclain24°法蘭德國(guó)標(biāo)準(zhǔn)德國(guó)DIN（德國(guó)工業(yè)標(biāo)準(zhǔn)）是常用的管接頭。所謂的公制管接頭通常是指DIN

11、管接頭。其法蘭為標(biāo)準(zhǔn)的61型或62型法蘭（-10除外）。 DIN 24°錐球頭螺紋說明：DIN24°錐球頭可以與圖示的三種內(nèi)螺紋相配合。外螺紋接頭為球頭公制直螺紋具有24°錐座和一個(gè)球頭沉孔，該孔與所用的管接頭的內(nèi)管外徑相配，與外螺紋相配的內(nèi)螺紋包括帶O形圈，公制管接頭的24°錐球頭內(nèi)螺紋，或通用24°或60°錐球頭內(nèi)螺紋等。 DIN 60°錐球頭螺紋說明：DIN60°錐球頭外螺紋接頭只能與通用24°或60°錐球頭內(nèi)螺紋接頭配合。外螺紋為公制直螺紋並帶60°錐座。內(nèi)螺紋為公制直螺紋並帶

12、通用24°和60°錐座。當(dāng)使用錐座角量規(guī)測(cè)量錐角時(shí)，應(yīng)使用30°錐角量規(guī)。（使用錐座角量規(guī)沿接頭中心線進(jìn)行測(cè)量。） DIN 3852，A型和B型管接頭（直螺紋）說明：DIN3852 A型和B型外螺紋管接頭可以與下圖所示的DIN內(nèi)螺紋管接頭配合。A型和B型外螺紋及內(nèi)螺紋管接頭均為直螺紋。圖1是指公制直螺紋，而圖2是指惠氏標(biāo)準(zhǔn)直螺紋。當(dāng)密封圏（A型）或密封面（B型）與內(nèi)螺紋端口的密封面配合時(shí)形成密封。DIN3852 A型和B型管接頭有兩種類型；輕型（L）系列和重型（S）系列。DIN 3852 C型公制和惠氏標(biāo)準(zhǔn)錐螺紋接頭說明：DIN 3852 C型管接頭既可以是公制螺

13、紋也可以是惠氏英制螺紋。外螺紋只能與圖示的內(nèi)螺紋配合。內(nèi)、外管接頭均為錐螺紋。表1是指公制錐螺紋而表2是指惠氏標(biāo)準(zhǔn)錐螺紋。密封在螺紋處形成。DIN 3852 C型管接頭有三種系列：超輕型系列(LL)，輕型系列(L)和重型系列(S)。公制壓套式管接頭總成說明公制壓套式管頭總成由連接在外接頭上的三個(gè)部件組成。這三個(gè)部件分別是：管芯壓套和公制螺母。螺母裝配在管芯上然後再裝配壓套(見圖) 。DIN輕型系列總成使用DIN輕型系列公制螺母而DIN重型系列總成使用DIN重型系列公制螺母。壓套和管芯根據(jù)所需的內(nèi)管外徑選擇。日本標(biāo)準(zhǔn)在日本有兩種比較常用的管接頭1.所有的小松設(shè)備均採(cǎi)用帶有30°錐座和公

14、制細(xì)牙螺紋的管接頭。所有的法蘭均為61型或62型法蘭（-10*除外）。2.其他大部分日本設(shè)備採(cǎi)用帶有30°錐座和英制標(biāo)準(zhǔn)直管螺紋的管接頭，通常稱為JIS（日本工業(yè)標(biāo)準(zhǔn)）管接頭。這些管接頭與英制管接頭不可互換，因其錐面方向相反。所有的法蘭均為61型或62型法蘭（-10*除外）。日本30°錐角直螺紋說明：日本30°錐角外螺紋接頭只能與日本30°錐角內(nèi)螺紋配合。內(nèi)、外螺紋均為直螺紋並帶30°錐座。其密封在30°錐座處形成。日本30°錐角接頭上的螺紋符合JIS B 0202標(biāo)準(zhǔn)，其與BSPP螺紋相同。英國(guó)和日本接頭均帶有30

15、6;錐座，但二者不可互換，因英國(guó)接頭錐座與日本接頭錐座方向相反。 日本30°錐管螺紋說明：日本錐管螺紋接頭與BSPT（錐螺紋）接頭完全相同，並完全可以互換。因日本接頭沒有30°錐角，故不能與BSPP內(nèi)螺紋相配合。這種螺紋符合JIS B 0203標(biāo)準(zhǔn)，與BSPT螺紋相同。日本錐管螺紋接頭的密封在螺紋處形成。小松型30°錐角直螺紋說明：小松型30°錐角直螺紋接頭與日本30°錐角直螺紋接頭除了在螺紋方面有所差別外，其它方面完全相同。小松型接頭採(cǎi)用公制細(xì)牙螺紋，該螺紋符合JIS B 0207標(biāo)準(zhǔn)。小松型接頭在其30°錐角處密封。小松型法蘭接頭

16、說明：小松型法蘭接頭與SAE 61型法蘭接頭近似，並完全可以互換。各種規(guī)格法蘭的O形圏尺寸不相同。當(dāng)使用SAE型法蘭更換小松型法蘭時(shí)，一定要使用SAE型O形圏。Product ManualCurrently there are five kinds of fitting systems, which are often used for hydraulic connection. They are described as follows by area or countrygeography or nation:North American StandardNPTFDescription：A

17、 kind of dry sealed thread that is suited fit for taper pipes to deliver fuels, it can be used in both male and female thread end fittings. NPTF male threads can work with NPTF , NPSF or NPSM female threads. Though similar, NPTF and BSPT pipe fittings are not interchangeable as the former are differ

18、ent in pitch and thread angle (60°) from the latter (55°).JIC37° taper female thread fittingsDescription：JIC 37° taper: The Society of Automotive Engineers (SAE) stipulates that 37° taper or tapered collets can be used in high-pressure hydraulic pipelines. Such pipe fittings

19、 are often called JIC pipe fittings. JIC male threads can only fit with JIC female threads. They are straight and have a 37° tapered face. JIC female threads are also straight and have a 37° tapered face. The sealing forms at the 37° tapered face. Threads of some measurements are iden

20、tical withSAE 45° tapered threads, so the taper should be measured carefully in order to distinguish between them. SAE 45° taper male thread fittings Description：SAE (45° taper): This is a term for pipe fittings of 45° taper or tapered collets. Soft brass pipes often use such fit

21、tingsas the material can be machined easily into a 45° angle. Such fittings are perfect for low pressure applications, like fuel pipelines and cooling pipelines.SAE 45° taper male threads can only fit with SAE 45° taper female threads. SAE male threads are straight and have a 45°

22、 tapered face.SAE female threads are also straight and have a 45° tapered face. The sealing forms at the 45° tapered face. Threads of some measurements are identical with SAE 37° tapered threads, so the taper should be measured carefully in orderto distinguish between them. O ring end

23、 sealing male thread fittingsExplanation: O shape circle of hold seal up exterior thread can only sum O shape a circle of faced sealing female screw cooperation,Exterior thread is straight thread bring O shape a circle; Female screw is straight thread bring seal up end face, Exterior thread at O sha

24、pe a circle place seal up, But female screw at seals up end face place seal up. O shape quan flange- SAE J518Say Ming Dynasty: SAE J518SAE 61 type sum 62 type four bolt march-past flange usually at worldwide in extensive should be used for connect pump and motor. This place has three kinds of except

25、ions situations; 1. Time rides coefficient- 10, Not SAE gauge, But area but applies to very generally beside North America 2. Carter that tie style flange, Possesses a compare thick flange ( Watches middle size" C " ) , It external diameter with SAE 62 type flange external diameter same bi

26、g. 3. Poclain flange, It with SAE flange root different. Male weighFlange Size61 Type（FL）62 Type（FL）Carter that tie style（FLC）FlangeExternaldiameterABCFlangeExternaldiameterABCFlangeExternaldiameterABC1/21.188 0.688 1.500 0.265 1.250 0.718 1.594 0.305 5/81.3380.265 3/41.500 0.875 1.875 0.265 1.625 0

27、.937 2.000 0.345 1.625 0.938 2.000 0.560 11.750 1.031 2.0620.315 1.875 1.093 2.250 0.375 1.875 1.094 2.250 0.560 1 1/4 2.0001.188 2.3120.315 2.125 1.250 2.625 0.405 2.215 1.250 2.625 0.560 1 1/2 2.3751.406 2.7500.315 2.500 1.473 3.125 0.495 2.500 1.438 3.125 0.560 2 2.8121.688 3.062 0.375 3.125 1.75

28、0 3.812 0.495 3.125 1.750 3.812 0.560 2 1/2 3.3122.000 3.500 0.375 3 4.0002.438 4.188 0.375 3 1/2 4.500 2.750 4.750 0.422 4 5.000 3.062 5.125 0.422 5 6.000 3.625 6.000 0.422 O shape a circle of plane seal up fix type exterior thread jointExplanation: Ases O shape a circle with female screw joint on

29、plane contact time form seal up on exterior thread joint, Can use elastomer seal up come control leakage at hydraulic power control system, And at prevents leak function quite under important situation, Can adopt this a kind of tube joint.Presses sum of style administer jointSay Ming Dynasty: Presse

30、s sum of style fix type exterior thread joint can only with press sum of style female screw nut and press a sum of cooperation. Exterior thread joint is straight thread bring 24° wimble. Female screw head is straight thread and ha as seal up microbus press sum of. It seals up at press sum of wi

31、th exterior thread joint 24° wimble between, Presses sum of with female screw joint in administer between form.British Standard SAE falls conical surface jointThinks all overseas thread average for metric system, This is a misapprehension. Usual not this, There is two kinds of in common use thr

32、ead forms- Meter screw sum benefit surname standard thread ( BSP) . British Standard straights administer ( BSP) Thread, Too calls benefit surname standard thread. It already can be straight thread ( BSPP) , Too can be taper thread ( BSPT) , Average has fall conical surface. It flange with SAE61 typ

33、e or 62 type flange analogous ( - 10* Exclusion) . Port connects usually by BSPP thread. It seals up adopt soft metal gland ring. BSPP ( Straight) Exterior thread can with BSPP ( Straight) Female screw or female screw Port cooperation. BSPP exterior thread is straight thread and bring 30° wimbl

34、e. BSPP female screw too is straight thread and bring 30° wimble. Female screw Port is straight thread and bring seal up end face. Port place will seal up by O shape quan or soft metal fil lup quan form on exterior thread joint. BSPP ( Straights thread) Joints with NPSM joint analogous but can

35、not exchange. It most size threads screw pitch different, Thread dental pattern jiao is 55°, But NPSM thread dental pattern jiao is 60° ( - 10 right and wrongs SAE specification's flange) British Standard straights administer thread ( BSP) Say Ming Dynasty: British Standard straights a

36、dminister ( BSP) Thread, Too calls benefit surname standard thread. It already can be straight thread( BSPP) , Too can be taper thread ( BSPT) , Average has fall conical surface. It flange with SAE61 type or 62 type flange analogous ( - 10* Exclusion) . Port connects usually by BSPP thread. It seals

37、 up adopt soft metal gland ring. BSPP ( Straight) Exterior thread can with BSPP ( Straight) Female screw or female screw Port cooperation. BSPP exterior thread is straight thread and bring 30° wimble. BSPP female screw too is straight thread and bring 30° wimble. Female screw Port is strai

38、ght thread and bring seal up end face. Port place will seal up by O shape quan or soft metal fil lup quan form on exterior thread joint. BSPP ( Straights thread) Joints with NPSM joint analogous but can not exchange. It most size threads screw pitch different, Thread dental pattern jiao is 55°,

39、 But NPSM thread dental pattern jiao is 60° ( - 10 right and wrongs SAE specification's flange) British Standard wimbles administer thread ( BSPT)Say Ming Dynasty: BSPT ( Wimble) Exterior thread can with BSPT ( Wimble) Female screw or BSPP ( Straight) Female screw cooperation. BSPT exterior

40、 thread is taper thread. Ases it with BSPT ( Wimble) Female screw or BSPP ( Straight) Female screw Port cooperation time, Form seal up at thread place. BSPT joint with NPTF joints approximation but can not exchange. It most threads screw pitch different, Thread dental pattern jiao is 55°, But N

41、PSM thread dental pattern jiao is 60°France standardFrance GAZ is in common use tube joint. This a kind of joint is meter screw and bring 24° wimble. With Germany DIN administersjoint analogy, But it thread at some size on different from. Though the two all is meter screw, But France all s

42、pecification administerjoint average adopt fine pitch thread, But Germany DIN administers joint dimension compare big, Adopts coarse thread. Most Port connections average for flange connection. France standard flange with SAE sum hellip standard flange different; It flange end face have a prominent

43、convex platform. This a kind of flange be called Poclain type flange. 1 GAZ24°2 GAZ Poclain24° flangeGermany standardGermany DIN ( Germany industrial standard) Is in common use tube joint. So-called metric system administer joint usually is point DIN administer joint. It flange is normativ

44、e 61 type or 62 type flange ( - 10 exclusions) . DIN 24° wimbles ball a threadSay Ming Dynasty: DIN24° wimbles ball head can with three kinds of pictorial female screws look cooperation. Exterior thread joint for ball a metric system straight thread possess 24° wimble sum a ball head

45、sink hole, Should hole and required administer joint in administer external diameter look match, With exterior thread looks match female screw include bring O shape a circle, Metric system administers joint 24° wimble ball a female screw, Or uses general 24° or 60° wimble ball a femal

46、e screw. DIN 60° wimbles ball a threadSay Ming Dynasty: DIN60° wimbles ball a exterior thread joint can only with use general 24° or 60° wimble ball female screw joint cooperation. Exterior thread for metric system straight thread and bring 60° wimble. Female screw for metri

47、c system straight thread and bring use general 24° sum 60° wimble. Ases use wimble a corner gauge survey wimble corner time, Should use 30° wimble a jiao gauge. ( Uses wimblea corner gauge along joint camber line proceed survey. )DIN 3852, A type sum B type tube joint ( Straights thre

48、ad)Say Ming Dynasty: DIN3852 A type sum B type exterior thread administer joint can with next picture show DIN female screw administer joint cooperation. A type sum B type exterior thread and female screw administer joint average for straight thread. Pictures one is point metric system straight thre

49、ad, But picture 2 is point benefit surname standard straight thread. Will as seal up quan ( A type) Or dense cover ( B type) With female screw Port's dense cover cooperation time form seal up. DIN3852 A type sum B type administer joint have two kinds of types; Light-duty ( L) Series sum heavy (

50、S) Series. DIN 3852 C type metric system sum benefit surname standard taper thread jointSay Ming Dynasty: DIN 3852 C type administer joint already can be meter screw will too can be benefit surname English make thread. Exterior thread cans only with pictorial female screw cooperation. In, Outside ad

51、ministers joint average for taper thread. Will watch one be point metric system taper thread but watch 2 be point benefit surname standard taper thread. Seals up form at thread place. DIN 3852 C type administers joint have three kinds of serieses: Exceeds light-duty series ( LL) , Light-duty series

52、( L) Sum heavy series ( S) . Metric system presses sum of style administer joint always becomesSay Ming Dynasty: Metric system presses sum of style administer a always becomes by connect out joint on three parts composing. This three parts difference is: Will administer core press sum of sum metric

53、system nut. Nut assemble at administer core on will again assemble press sum of ( Sees picture) . DIN light-duty will be series always becomes use DIN light-duty series metric system nut but DIN heavy series always becomes use DIN heavy series metric system nut. Press sum of sum administer core acco

54、rding to need in administer external diameter choice. Japan standardThere is two kind of compare in common use tube joint at Japan ( 1) All small loose equipment average adopt ha 30° wimble sum metric system fine pitch thread administer joint. All flange average for 61 type or 62 type flange (

55、- 10* Exclusion) . ( 2) Other most Japans equipment adopt ha 30° wimble sum English make standard straight administer thread administer joint, Usually call as JIS( Japan Industrial Standard) Administers joint. These administers joint with English make administer joint can not exchange, Because it conical surface direction con