Q1: Dab tsi txhais tau tias Hastelloy B-2 capillary raj, thiab nws tsim li cas?
A: A cev capillaryyog txhais raws li ib tug me me - txoj kab uas hla, precision raj nrog ib tug sab nraud txoj kab uas hla feem ntau xws li los ntawm0.5mm txog 6.0mm (0.020-0.236 nti)thiab phab ntsa thickness ntawm0.05mm txog 1.0mm (0.002-0.039 nti). Lub sij hawm "capillary" originates los ntawm lub raj lub peev xwm los kos cov kua los ntawm capillary nkaus, tab sis nyob rau hauv industrial siv, nws feem ntau yog hais txog nws me me, meej qhov ntev. Hastelloy B-2 capillary raj yog tsim los rau nruj heev kam rau ua, feem ntau nrog OD tolerances ntawm ± 0.02 hli (± 0.0008 nyob rau hauv) thiab phab ntsa thickness tolerances ntawm ± 10%.
Manufacturing Hastelloy B-2 capillary raj yog ib qho tshwj xeeb, ntau- cov txheej txheem txheej txheem uas nyuaj tshwj xeeb vim yog cov hlau tsis muaj zog heev rau cov nag lossis daus theem thiab kev ua haujlwm ceev ceev:
Initial hollow billet ntau lawm- Cov txheej txheem pib nrog qhov loj dua - txoj kab uas hla seamless B-2 yeeb nkab (feem ntau 20–50 mm OD) ua los ntawm extrusion los yog rotary tho ntawm lub nqus tsev vacuum -induction-melted (VIM) billet. Cov yeeb nkab no yog tov annealed (1060-1100 ° C / 1940-2010 ° F) thiab dej quenched.
Txias daim duab- Lub raj yog rov txias dua los ntawm cov kab ntawm tungsten carbide lossis pob zeb diamond tuag, nrog lub mandrel sab hauv los tswj lub puab txoj kab uas hla. Txhua qhov dhau los txo qhov OD thiab phab ntsa tuab los ntawm 15-25%. Vim tias B-2 ua haujlwm hnyav heev,intermediate tov annealing yuav tsum tau tom qab txhua txhua 25-30% txo nyob rau hauv cross-sectional cheeb tsam- ntau zaus dua li B-3 lossis C-276. Lub annealing yuav tsum tau ua nyob rau hauv ib tug txo los yog inert cua (hydrogen los yog argon) los tiv thaiv nto oxidation.
Pilgering (rau me diameters)- Rau cov raj capillary hauv qab 2 hli OD, feem ntau siv lub tshuab txias pilgering (rotary forging) feem ntau. Cov txheej txheem no siv ob qhov grooved tuag uas rauj lub raj hla ib lub mandrel tapered, ua kom tau txais kev txo loj (70-85%) hauv ib zaug. Pilgering ua rau lub ntsej muag smoother thiab cov phab ntsa tuab dua li kev kos duab ib leeg, tab sis cov deformation siab yuav tsum tau ceev faj kom tsis txhob overheating.
Thaum kawg annealing thiab straightening- Tom qab ncav cuag qhov ntev kawg, lub raj capillary yog cov tshuaj annealed kom rov ua kom tag nrho corrosion thiab ductility.Kev ywg dej sai sai yog qhov yuav tsum tau ua- qeeb txias los ntawm 600-900 ° C (1110-1650 ° F) ntau yuav ua rau nag lossis daus ntawm Ni₄Mo thiab Ni₃Mo theem, ua rau lub raj tsis muaj txiaj ntsig. Tom qab ntawd lub raj yog straightened (siv rotary los yog roller straighteners) thiab txiav mus rau qhov ntev ntev (feem ntau 1-6 meters, tab sis coils mus txog 50 meters yog ua tau rau me me diameters).
Nto xov- Rau cov ntawv thov tseem ceeb (piv txwv li, kev ntsuas ntsuas), lub raj yuav raug electropolished lossis mechanically polished kom ua tiav qhov roughness ntawm sab hauv (Ra) ntawm 0.2-0.4 μm (8-16 μin). Qhov no txo qis cov dej tuav- nce thiab tiv thaiv cov khoom seem.
Daim ntawv tseem ceeb:Vim B-2 lub thermal instability, ntau manufacturers tau tso tseg tsis tsim B-2 capillary hlab, muab B-3 hloov. B-3 muab zoo tib yam corrosion kuj nyob rau hauv txo acids nrog ntau zoo fabricability thiab thermal stability. Rau cov qauv tsim tshiab, B-3 capillary raj yog pom zoo tshaj B-2.
Q2: Dab tsi yog qhov kev lag luam tseem ceeb ntawm Hastelloy B-2 capillary raj?
A:Hastelloy B-2 lub raj capillary yog siv rau hauv cov ntawv tshwj xeeb uas xav tau kev thauj mus los zoo, txhim khu kev qha lossis muaj cov tshuaj tiv thaiv kom tsis txhob muaj kua qaub ntau heev -tshwj xeeb tshaj yog hydrochloric acid-ntawm cov nplai me, qhov twg cov cuab yeej tsim thiab ntsia ua ntej kev qhia txog B-3. Cov ntawv thov tseem ceeb suav nrog:
Analytical instrumentation rau HCl xyuas- Hauv cov nroj tsuag tshuaj laus, cov kws tshuaj ntsuam xyuas online tsis tu ncua ntsuas hydrochloric acid concentration hauv cov txheej txheem ntws. B-2 lub raj capillary ua haujlwm raws li cov qauv kab (0.5–2.0 mm ID) txuas cov txheej txheem yeeb nkab rau lub ntsuas ntsuas. Cov kab me me ua kom cov qauv thauj sai nrog qhov ntim tsawg kawg nkaus. Txawm li cas los xij, cov tshuab no yuav tsum tau ua tib zoo tswj kom tsis txhob muaj cov kab mob oxidizing.
Siab -siab ua kua chromatography (HPLC) systems- Qee cov kab ke HPLC qub uas txheeb xyuas cov qauv acidic (xws li, cov tshuaj intermediates hauv dilute HCl) siv B-2 capillary tubing rau cov qauv txhaj tshuaj thiab kab sib txuas. Cov hlau tiv thaiv lub sijhawm txawb (uas yuav muaj phosphoric lossis hydrochloric acid buffers) ntawm qhov siab txog 400 bar (5800 psi).
Cov tshuaj txhaj tshuaj nyob rau hauv cov roj thiab cov qhov dej- Cov laus txhim kho cov roj rov qab (EOR) cov tshuab siv B-2 capillary hlab (3-6 hli OD × 1-2 mm ID) ua cov kab hauv qab rau cov concentrated hydrochloric acid (15-28% HCl) ntawm qhov siab ntawm 50-100 bar (700-1500 psi). Cov no feem ntau raug hloov nrog B-3 lossis C-276 tubing thaum lawv ua tsis tiav.
Laboratory thiab pilot cog reactors- Cov chaw soj ntsuam tshawb fawb uas muaj keeb kwm siv B-2 rau hydrochloric acid cov tshuaj tiv thaiv kev tshawb fawb tseem yuav tseem muaj B-2 capillary hlab hauv lawv cov kab noj, cov qauv ntsuas, thiab ntsuas cov kais dej. Txawm li cas los xij, feem ntau tau tsiv mus rau B-3 rau kev sim tshiab.
Thermocouple sheathing- Zoo- ntsuas cov thermocouples tso rau hauv B-2 capillary raj rau kev tiv thaiv kub hydrochloric acid vapor. Txoj kab uas hla me me muab cov lus teb thermal sai thaum tiv thaiv cov xaim thermocouple.
Kev txwv tseem ceeb:B-2 capillary tubes yogtsis haumrau txhua daim ntawv thov uas oxidizing hom (ferric ions, yaj oxygen, nitric acid) tuaj yeem tshwm sim. Txawm tias cov kab mob tuaj yeem ua rau corrosion sai. Vim li no, B-2 yog qhov tsawg zuj zus hauv cov cuab yeej tshiab, thiab cov neeg siv tau txhawb kom tsim nyog rau lawv cov txheej txheem rau B-3 lossis C-276 capillary hlab.
Q3: Dab tsi yog qhov tseem ceeb ntawm kev tsim thiab kev txiav txim siab rau Hastelloy B-2 capillary raj?
A:Kev ua haujlwm nrog Hastelloy B-2 capillary raj yog qhov nyuaj dua li B-3 lossis stainless hlau vim tias cov hlau tsis muaj zog heev rau cov cua sov, ua haujlwm hnyav, thiab kev sib kis. Cov kev xav hauv qab no yog qhov tseem ceeb:
1. Txiav:Cov hlab ntsha capillary yuav tsum tau txiav kom huv si yam tsis tau deforming lub lumen.Abrasive txiav- tawm lub log(nyias, 0.5-1.0 mm tuab) yog nyiam.Hluav taws xob tawm machining (EDM)muab qhov huv tshaj plaws, burr - txiav dawb.Tsis txhob siv lub saw saw- cov cua sov tsim tawm tuaj yeem tshaj 600 ° C (1110 ° F) hauv zos, ua rau cov nag lossis daus ntawm qhov kawg txiav. Tom qab txiav, deburr nrog cov pob zeb zoo abrasive los yog cov cuab yeej capillary deburring. Txhua qhov burr uas tawm mus rau hauv lub qhov dej tuaj yeem tso dej los yog tawg.
2. Khoov:B-2 capillary raj feem ntau yog khoov kom haum rau hauv cov ntsuas ntsuas.Mandrel khoov (using a flexible internal mandrel) is essential for tubes with an OD:wall ratio >10: 1 tiv thaiv kinking. Qhov tsawg kawg nkaus khoov vojvoog rau B-2 yog5 × OD(piv rau 3 × OD rau B-3) vim tias B-2 yog qhov yooj yim rau kev tawg.Thaum tshav kub kub- pab khoov yog txwv nruj heev- Cov cua sov hauv zos yuav ua rau cov theem intermetallic. Tsuas yog khoov txias yog tso cai. Tom qab khoov, lub raj yuav tsum tau muab tshuaj annealed (1060-1100 ° C) thiab dej quenched los txo cov kev ntxhov siab.
3. Vuam thiab koom nrog:Vuam B-2 capillary raj yognyuaj heev thiab feem ntau tsis pom zoo. Cov huab cua me me ua rau kev tswj cua sov yuav luag tsis tuaj yeem, thiab qhov kev pheej hmoo ntawm cov nag lossis daus hauv cov cua sov- muaj kev cuam tshuam loj heev. Hloov chaw, sivhigh-siab cone-thiab-ferrule fittings(xws li Swagelok, Parker) ua los ntawm B-2, B-3, los yog C-276. Cov fittings no siv lub ferrule uas tuav lub raj OD yam tsis muaj vuam. Yog tias qhov vuam tsis tuaj yeem zam tau (xws li, rau kev sib dhos), siv orbital GTAW nrog cov tsis muaj: tam sim no 5-10 amps, voltage 8-10 V, mem tes zaus 50-100 Hz, thiabYuav tsum tau argon rov qab ntxuav. Lub vuam yuav tsum tau soj ntsuam los ntawm radiography los yog dye penetrant, thiab HAZ hardness yuav tsum tau kuaj (yuav tsum yog ≤100 HRB).
4. Nto huv thiab paug:B-2 capillary tubes yog cov rhiab heev rau cov kab mob hlau. Hlau hais los ntawm kev tuav, txiav, lossis cuab yeej yuav ua rau galvanic pitting hauv HCl kev pabcuam.Yuav tsum muaj cov txheej txheem nruj:
Siv cov hnab looj tes huv, lint-dawb nitrile (tsis txhob muaj tes liab qab).
Khaws cov tub rau hauv cov hnab yas kaw nrog cov desiccant.
Tag nrho cov cuab yeej (cutters, mandrels, ferrules) yuav tsum yog carbide los yog stainless hlau - tsis carbon steel.
Ua ntej kev teeb tsa, yaug lub raj nrog acetone, tom qab ntawd ntxuav hauv 10% HNO₃ + 2% HF ntawm 50 ° C rau 10 feeb, yaug nrog dej deionized, thiab qhuav nrog nitrogen.
5. Kev tshuaj xyuas:Vim qhov me me thiab B-2 qhov rhiab heev, kev tshuaj xyuas nruj yog qhov tseem ceeb:
Eddy tam sim no xeem (ET)rau ASTM E426 - 100% ntawm lub raj ntev kom pom qhov chaw thiab ze rau - qhov chaw tsis zoo.
Hydrostatic los yog pneumatic siab kuaj- Txhua lub raj ntev sim mus rau 1.5 × ua haujlwm siab (tsawg kawg 50 bar). Rau cov ID me me (<0.5 mm), pneumatic testing with helium is preferred.
Kev kuaj Hardness(micro-Vickers ntawm lub raj hla-section) - Yuav tsum yog ≤220 HV (≤100 HRB). Cov nqi siab dua qhia tias nag lossis daus intermetallic.
Kev kuaj Ferroxyl- Tshawb xyuas cov hlau tsis huv (xiav staining=tsis lees paub).
6. Cia thiab txee lub neej: B-2 capillary tubes should be stored in a clean, dry, inert atmosphere (argon-purged cabinet) if not used immediately. Over time, even atmospheric moisture and chlorides can cause surface pitting. For long-term storage ( >6 lub hlis), nqus tsev - foob nrog desiccant.
Muab cov kev cai nruj heev no, cov neeg siv feem ntau tau hloov B-2 capillary hlab nrog B-3, uas muaj kev tiv thaiv corrosion zoo tib yam nrog cov ntaub ntawv zoo dua thiab thermal stability.
Q4: Dab tsi yog qhov kev ntsuas siab thiab cov yam ntxwv ntws ntawm Hastelloy B-2 capillary raj?
A:Txawm hais tias nws qhov me me, Hastelloy B-2 capillary raj tuaj yeem ua rau muaj kev kub ntxhov siab heev vim yog kev sib xyaw ntawm cov alloy lub zog siab thiab qhov zoo ntawm cov duab ntawm cov kab me me. Txawm li cas los xij, muaj cov theem ntawm intermetallic (yog tias ua tsis tiav) tuaj yeem txo qis kev ntsuas siab.
Kev ntsuas ntsuas ntsuas:Lub siab tawg rau qhov nyias nyias - cov phab ntsa phab ntsa yog muab los ntawm lub hoop stress formula:
P=2 × S × t / (OD – t)
qhov twg:
P=tawg siab (MPa lossis psi)
S=qhov kawg tensile lub zog (≥750 MPa / 109 ksi rau kom zoo annealed B-2)
t=phab ntsa thickness (mm los yog hauv)
OD=sab nraud txoj kab uas hla (mm los yog hauv)
Piv txwv suav rau B-2 capillary raj qhov ntev:
| OD (mm) | Phab ntsa (mm) | ID (mm) | Kub siab (bar) | Ua haujlwm siab (bar) * |
|---|---|---|---|---|
| 1.6 | 0.3 | 1.0 | 277 bar (4020 psi) | 92 bar (1340 psi) |
| 1.6 | 0.4 | 0.8 | 400 bar (5800 psi) | 133 bar (1930 psi) |
| 3.2 | 0.5 | 2.2 | 241 bar (3500 psi) | 80 bar (1160 psi) |
| 3.2 | 0.7 | 1.8 | 358 bar (5190 psi) | 119 bar (1730 psi) |
| 6.0 | 1.0 | 4.0 | 280 bar (4060 psi) | 93 bar (1350 psi) |
* Kev ua haujlwm siab xav tias muaj kev nyab xeeb ntawm 3 tiv thaiv tawg.
Kev ceeb toom tseem ceeb:Cov kev suav no suav hais tias yog kev daws teeb meem zoo-annealed B-2 yam tsis muaj theem intermetallic. Yog hais tias lub raj tau raug rau 600-900 ° C (xws li, thaum lub sij hawm vuam tsis zoo los yog kub heev los ntawm kev txiav), lub tensile lub zog yuav poob mus rau 400-500 MPa, txo burst siab los ntawm 30-40%. Tsis tas li ntawd, cov hlab ntsha tuaj yeem ua tsis tiav los ntawm cov pob txha tawg ntawm qhov siab zoo hauv qab qhov ntsuas qhov tawg.
Flow yam ntxwv:Ntws los ntawm lub raj capillary ua raws li Hagen -Poiseuille kab zauv rau laminar ntws:
Q=(π × ΔP × r⁴) / (8 × μ × L)
Flow tus nqi yog proportional rau lubplaub lub zog ntawm lub voj voog sab hauv- 10% kev hloov pauv hauv ID ua rau 46% kev hloov pauv hauv tus nqi ntws. Yog li ntawd, kev tswj xyuas tus ID yog qhov tseem ceeb. B-2 capillary raj feem ntau yog tsim los rau ID kam rau ua ntawm ± 0.02 hli rau qhov ntau thiab tsawg hauv qab 2 hli ID.
Piv txwv tus nqi ntws (dej ntawm 20 ° C, μ=0.001 Pa·s):
| ID (mm) | Ntev (m) | ΔP (bar) | Tus nqi ntws (mL / min) |
|---|---|---|---|
| 0.5 | 1.0 | 100 | 0.92 |
| 0.8 | 1.0 | 100 | 6.0 |
| 1.0 | 2.0 | 100 | 9.8 |
| 1.5 | 2.0 | 50 | 31.0 |
Kev txiav txim siab tshwj xeeb rau B-2:
Cua sov – At high pressure drops (>200 bar), viscous dissipation tuaj yeem ua kom sov cov kua dej. Rau cov concentrated HCl, qhov kub siab tshaj 80 ° C tuaj yeem ua kom corrosion.
Txuas – The small ID makes B-2 capillary tubes susceptible to plugging by particles >10% ntawm ID. Inlet lim (2-10 μm kiag li) yog qhov yuav tsum tau ua.
Kev tiv thaiv corrosion- Txawm tias tus nqi qis ntawm B-2 hauv HCl ntshiab (0.05–0.1 mm / xyoo) yuav maj mam nce ID thiab txo cov phab ntsa tuab. Rau cov ntawv thov mus sij hawm ntev (10+ xyoo), pib nrog cov phab ntsa tuab kom suav nrog kev xeb.
Vim lub thermal rhiab heev ntawm B-2, txhua qhov kev ntsuas siab yuav tsum tau derated los ntawm 20-30% yog tias lub raj tsis paub txog keeb kwm thermal. Rau kev tsim tshiab, B-3 capillary raj tau pom zoo.
Q5: Dab tsi cov qauv thiab cov kev xeem yuav tsum siv rau Hastelloy B-2 capillary raj?
A:Hastelloy B-2 capillary tube yog cov khoom tshwj xeeb, thiab cov qauv siv feem ntau tau hloov kho los ntawm cov yeeb nkab dav dav thiab cov yeeb nkab tshwj xeeb. Txawm li cas los xij, nws yog ib qho tseem ceeb uas yuav tsum nco ntsoov tias B-2 tab tom raug txiav tawm, thiab ntau cov qauv tau raug kho kom haum rau B-3. Cov qauv tseem ceeb siv tau yog:
Khoom thiab Dimensional Standards:
ASTM B 622 Cov khoom lag luam- Txheem Specification rau Seamless Nickel thiab Nickel-Cobalt Alloy Yeeb Nkab thiab Tube (nrog rau txhua qhov seamless tube loj, suav nrog qhov ntev capillary)
ASTM B626- Txheem Specification rau Seamless Nickel thiab Nickel-Cobalt Alloy Tube (redrawn, nruj dua kam rau ua; feem ntau hais rau cov raj capillary)
ASME SB-622 / SB-626- ASME code versions rau kev siv siab
ASTM B829 Cov khoom lag luam- Txheem Specification rau General Requirements rau Nickel thiab Nickel Alloy Seamless Yeeb Nkab thiab Tube (cov kev xav tau ntxiv)
Dimensional Tolerances (zoo rau siab -zoo B-2 capillary raj):
| Parameter | Ua siab ntev |
|---|---|
| Sab nraud txoj kab uas hla (OD) | ± 0.02 hli rau OD ≤3 hli; ± 0.05 hli rau OD 3-6 hli |
| Phab ntsa thickness (t) | ± 10% ntawm nominal |
| Sab hauv txoj kab uas hla (ID) | xam los ntawm OD thiab t; Kev hloov pauv raug ± 0.02 hli |
| Length (txiav pieces) | ± 1mm rau qhov ntev<500 mm; ±2 mm for longer |
| Kev ncaj | 0.5 hli rau 300 hli ntev |
| Nto roughness (ID, polished) | Ra ≤0.4 μm (16 μin) |
| Nto roughness (OD) | Ra ≤0.8 μm (32 μin) |
Yuav tsum tau kuaj rau B-2 Capillary Tube:
Kev tshuaj ntsuam xyuas tshuaj (ASTM E1473)- Txheeb xyuas Ni ≥68%, Mo 26–30%, Fe ≤2.0%, Cr ≤1.0%, C ≤0.02%, Si ≤0.10%. Tsawg carbon thiab silicon yog qhov tseem ceeb rau thermal stability.
Kev ntsuas tensile- Vim tias cov hlab capillary me me dhau rau cov qauv tensile qauv, kev sim ua rau ntawm tus neeg sawv cev loj dua - txoj kab uas hla ntawm tib lub tshav kub thiab kev tsim khoom. Yam tsawg kawg nkaus: tawm los ≥350 MPa, tensile ≥750 MPa, elongation ≥40%.
Kev sim hardness- Microhardness (Vickers, HV) ntawm lub raj hla -section. Txais tau ntau yam: 180-220 HV (≤100 HRB). Cov txiaj ntsig siab dua qhia tias nag lossis daus los yog ua haujlwm txias heev.
Intergranular corrosion test (ASTM G28 Txoj Kev A)- Ferric sulfate-sulfuric acid kuaj rau 120 teev. Corrosion tus nqi ≤12 hli / xyoo, tsis muaj intergranular nres. Qhov kev sim no yogtseem ceebrau B-2 vim tias theem intermetallic yuav ua rau muaj kev tawm tsam sai raws li cov ciam teb.
Simulated post-weld heat treatment (SPWHT) test- Ib qho piv txwv los ntawm tib lub tshav kub yog raug rau 700 ° C rau 1 teev (cua txias) thiab tom qab ntawd kuaj ib ASTM G28 Txoj Kev A. Qhov no txheeb xyuas qhov thermal stability. Ntau lub raj B-2 ua tsis tau qhov kev sim no, yog vim li cas B-3 nyiam dua.
Eddy tam sim no kuaj (ECT) rau ASTM E426- 100% ntawm lub raj nto (OD thiab ID) scanned. Txais: tsis muaj teeb liab tshaj 50% ntawm tus qauv siv rau 0.1 hli sib sib zog nqus notch.
Hydrostatic los yog pneumatic siab kuaj- Txhua lub raj tau sim rau 1.5 × ua haujlwm siab (tsawg kawg 50 bar). Rau cov ID me me (<0.5 mm), pneumatic testing with helium and a mass spectrometer is used (leak rate <1 × 10⁻⁹ mbar·L/s).
Visual thiab dimensional soj ntsuam- Nyob rau hauv 10-20 × magnification, tshuaj xyuas qhov tsis xws luag (nicks, khawb, dents, corrosion). Tus ID raug tshuaj xyuas los ntawm rov qab - teeb pom kev zoo lossis borescope.
Kev xaiv tab sis pom zoo kuaj rau cov ntawv thov tseem ceeb:
Kev kuaj Ferroxyl- Tshawb xyuas cov hlau tsis huv (xiav staining=tsis lees paub).
Kev ntsuam xyuas metallographic- Ntawm 500 × magnification, txheeb xyuas tsis muaj theem intermetallic (Ni₄Mo, Ni₃Mo) ntawm cov ciam teb.
Khoov xeem- Qauv raj khoov ib ncig ntawm lub mandrel ntawm 5 × OD uas tsis muaj qhov tawg.
Kev txheeb xyuas cov khoom zoo (PMI)- XRF phom kuaj ntawm txhua lub raj ntev kom paub tseeb tias muaj pes tsawg leeg (txawm tias XRF tsis tuaj yeem ntsuas carbon lossis silicon kom raug).
Ntawv pov thawj:Cov chaw tsim khoom yuav tsum muab daim ntawv pov thawj cov ntaub ntawv pov thawj (MTR) suav nrog:
Kub naj npawb thiab ntau ntau
Tshuaj ntsuam xyuas tau
Tensile thiab hardness tshwm sim
ASTM G28 corrosion test result (xws li SPWHT yog xav tau)
Eddy tam sim no thiab kev ntsuas siab
Nqe lus hais txog kev ua raws li ASTM B622 lossis B626
Daim ntawv tseem ceeb ntawm kev muaj:Ntau lub mills tau txiav tawm B-2 capillary tube ntau lawm vim qhov kev thov qis thiab qhov nyuaj ntawm kev tswj xyuas thermal stability thaum tsim khoom. Yog tias B-2 capillary tube yuav tsum tau hloov cov cuab yeej cuab tam qub, cia siab tias yuav siv sij hawm ntev ntev (6-12 lub hlis) thiab qhov kev txiav txim siab tsawg kawg nkaus.Rau txhua qhov kev tsim tshiab, Hastelloy B-3 capillary raj tau pom zoo- nws ua tau raws li cov qauv zoo tib yam, muaj kev tiv thaiv corrosion zoo tib yam hauv kev txo cov kua qaub, thiab muaj ntau yam thermal stability thiab fabricability. Cov neeg siv yuav tsum ua kom zoo dua lawv cov txheej txheem rau B-3 thiab hloov B-2 hlab nrog B-3 thaum lub sijhawm tu.
