Wɔ nneɛma a wɔyɛ mu no, mfiridwumayɛfo a wɔhwɛ nsɔano so no taa yɛ adwumayɛfo kuw bi a wɔhwehwɛ nneɛma pii sen biara.
Sɛ afiri no reyɛ adwuma sɛnea ɛsɛ a, obiara nnwen wo ho; nanso sɛ mfiri no nya nsu a ɛtwetwe (nsu, ngo, anaa gas) wɔ baabi a adetɔfo no wɔ no pɛ a, akyinnye biara nni ho sɛ onipa a odi kan a wobu akontaa no ne mfiridwumayɛfo a ɔhwɛ nsɔano so no.
Ɔdansi ho nimdefo no di kan hwehwɛ amena no nsusuwii mu, na osi so dua sɛ wɔatwe no pɛpɛɛpɛ sɛnea tolerance specifications kyerɛ. Afei IQC dwumadibea no hwɛ adwumayɛbea no amanneɛbɔ no mu, na wɔhwɛ sɛ nneɛma a adwumakuw akɛse de ma no du gyinapɛn ahorow a wɔhwehwɛ nyinaa ho. Awiei koraa no, asɛyɛde a ɛne sɛ wɔbɛhwehwɛ huammɔdi mu no da nsɔano mfiridwumayɛfo no so pɛpɛɛpɛ.
Woayi O-ring a asɛe no afi hɔ; na n’anim yɛ nea enni dɛm, na mpaapaemu anaa nnuru a asɛe ho sɛnkyerɛnne biara nni mu. Nsakrae biako pɛ a wɔyɛe ne sɛ na wɔayɛ no petee na wɔantumi ansan ansan ankɔ sɛnea na ɛte kan no.
Saa bere yi, sɛ wɔde wɔn adwene si tensile strength ne Shore hardness values a wɔakyerɛw wɔ adetɔnfo no nneɛma ho nkyerɛkyerɛmu mu nkutoo so a, ebia wontumi nhu nea ɛde huammɔdi ba ankasa.
Wɔ ahemman a sealed polymer nneɛma no, bere tenten -sealing adwumayɛ mpɛn pii no, ɛnyɛ nneɛma no den anaa tensile ahoɔden na ɛkyerɛ, na mmom ɛnam parameter a wɔtaa bu no adewa so: compression set (CS).
Momma yɛnhwehwɛ saa parameter yi mu kɔ akyiri mfi akwan abiɛsa so.
0 1
Nsɔano – dɛn ankasa na wɔresɔ ano?
Ansa na yɛbɛka compressive permanent deformation ho asɛm no, ɛho hia sɛ yɛsiesie mfiridwuma ho adwene a ɛnteɛ a wɔtaa nya: sealing nnyina "blocking" so na mmom "supporting" so.
mfoni
Sɛ wode silicone O-ring hyɛ dade groove no mu na wokyekye flange no mu den a, silicone no mia (mpɛn pii no ɛyɛ 15%–30%).
Silicone yɛ ade a ɛyɛ den yiye. Sɛ wɔmia a, wɔde ahoɔden kyinkyim ne molecule nkɔnsɔnkɔnsɔn no, na ɛma tumi a emu yɛ den a ɛsan ba (contact stress) a ɛhwehwɛ sɛ ɛsan kɔ ne mfitiase tebea no mu.
Saa tumi a ɛsan ba yi tia dade ɔfasu no denneennen; wɔ nsusuwii mu no, bere tenten a ɛboro nsu a ɛwɔ mu no nhyɛso so no, aduru no rentu koraa.
Enti, ade titiriw a ɛwɔ nsɔano mu ne tumi a ɛyɛ den a silicone molecule nkɔnsɔnkɔnsɔn de ma bere nyinaa wɔ nhyɛso ase, na ɛma wotumi bata dade ani denneennen.
0 2
Dɛn na ɛma nsɔano no di huammɔ?
Esiane sɛ nsɔano gyina tumi a ɛsan de ba no so nti, sɛ tumi yi yera a, dɛn na ɛba?
Dɛn ne compressive permanent deformation?
Yɛde silicone gel no yɛɛ petee 25%, tow no wɔ fononoo mu wɔ digrii 120 mu nnɔnhwerew 70, afei yeyii no na yɛmaa no yɛɛ nwini na ɛsan kɔɔ ne mfitiase tebea mu.
Sɛ ebetumi asan de ne mfitiaseɛ kɛseɛ no aba koraa a, CS=0% (elastomer a ɛyɛ pɛ a enni hɔ ankasa).
Sɛ ɛyɛ petee koraa na ɛnsan ahoɔden koraa a, CS=100% (a ɛkyerɛ sɛ abɛyɛ plastic a ɛyɛ den).
Dɛn nti na molecule nkɔnsɔnkɔnsɔn ntumi "nsan nkɔ wɔn mfitiase tebea mu"? Asɛm no da microscopic level no so:
Nipadua mu gyinabea – Adwennwen mu Ahomegye ne Nkɔnsɔnkɔnsɔn mu Nkyekyɛmu a Wɔsan Yɛ no
Silicone nam molecule nkɔnsɔnkɔnsɔn atenten a ɛka bom so na ɛba. Sɛ wɔde no hyɛ ɔhyew a ɛkɔ soro mu bere tenten a, .
Ɛtew ne mu nhyɛso so denam nkakrankakra a ɛtwetwe ne nhyehyɛe foforo so.
Ɛte sɛ nea woremia asaawa bɔɔl a ɛyɛ fĩ wɔ adaka bi ase afe biako-bedu bere a wubeyi afi mu no, na ayɛ nsakrae dedaw ma ɛne ne nsusuwii a ɛyɛ tratraa no ahyia na ɛkame ayɛ sɛ entumi nsan nnya ne mfitiase fĩ.
Saa honam fam "compromise" yi ma ahoɔden a ɛsan ba no so tew nkakrankakra.
Chemical level – Cross-linking bonds a ɛpaapae na wɔsan hyehyɛ no
Eyi ne ade a ɛho hia sen biara. Silicone a ɛyɛ den no gyina cross-linking nkitahodi a ɛda molecule nkɔnsɔnkɔnsɔn ntam (te sɛ sulfur-sulphur nkitahodi) so.
Wɔ ɔhyew a ɛkɔ soro ne nhyɛso a ɛkyɛ ase no, mfitiase cross-linking bonds no bubu, na ɛde elastic traction force a ɛyera ba.
Nea ɛho hia kɛse no, free radicals a ɛnam mpaapaemu so ba no bɛsan -yɛ cross-linked bonds foforo wɔ compressed tebea horow a ade no-atoto molecule nkɔnsɔnkɔnsɔn no mu yiye wɔ "flat state." Bere a wɔayi tumi a efi akyi no afi hɔ mpo no, nnuru foforo a ɛka bom yi mma ade no ntumi nsan nkɔ sɛnea na ɛte kan no.
Honam fam slip + nnuru a wɔsan ka bom=nhyɛso a ɛtra hɔ daa deformation.
CS bo a ɛkorɔn no ma silicone gel a ɛyɛ tratraa ne contact stress a ɛyɛ mmerɛw. Awiei koraa no, sɛ tumi a ɛsan ba no nnɔɔso sɛ wɔde toto nsu no nhyɛso ho a, nsu a ɛtwetwe no ba.
0 3
Ɔkwan bɛn so na ɛsɛ sɛ wodi eyi ho dwuma fi mfiridwuma mu?
Seesei a yɛate akwan a wɔfa so yɛ adwuma no ase no, yɛbɛyɛ dɛn akwati asiane yi bere a yɛreyɛ nsɔano ho nhyehyɛe na yɛrepaw nneɛma no?
1. Sɛ worekyerɛ CS data ase a, bere nyinaa ma sɔhwɛ tebea horow no mu nna hɔ.
Honam fam agyapade pon a nea ɔde ma no de ma no taa ka sɛ "permanent deformation under compression: 25%."Nanso, ɔhyew bɛn mu, wɔ nhyɛso dodow bɛn ase, na bere tenten ahe na wɔde susuw saa nneɛma yi?
Sɛ wɔsusu CS boɔ no wɔ 25% wɔ 100℃, ɛbɛtumi akɔ soro akodu bɛboro 50% wɔ adwumayɛ tebea ankasa a ɛyɛ digrii 150 mu ɛnam ɔhyew ne oxidative onyin a ɛkɔ ntɛmntɛm nti.
Ahwehwɛdeɛ titire ne sɛ, sɛ wɔresusu CS boɔ ho a, ɛnsɛ sɛ sɔhwɛ no mu hyeɛ no sua nsen afiri no adwumayɛ mu hyeɛ a ɛkyɛn so, na anyɛ yie koraa no ɛsɛ sɛ sɔhwɛ berɛ no yɛ nnɔnhwereɛ aduɔson anaa nnɔnhwereɛ 168. Data a ɛte saa nkutoo na ebetumi ayɛ nkyerɛkyerɛmu a ɛfata a wɔde paw nneɛma.
2. Fa w’adwene si cross-linking system no so sen sɛ wobɛma hardness akɔ soro anifurae so
Sɛ CS boɔ no ntumi nhyia ahwehwɛdeɛ no a, mmɔ mmɔden sɛ wobɛtua ka denam silicone gel hardness-hardness a wobɛma akɔ soro no so ntumi nsan daa deformation. Mmom no, ɛsɛ sɛ wɔde wɔn ho hyɛ mu no kyerɛ ade no nnuru cross-linking nhyehyɛe no.
Sɛ yɛfa NBR anaa EPDM sɛ nhwɛsoɔ a: atetesɛm sulfur vulcanization nhyehyɛeɛ yɛ sulfur-sulphur nkitahodi a ɛwɔ nkitahodi ahoɔden a ɛba fam, a ɛtaa bubu na ɛsakra wɔ ɔhyew a ɛkorɔn mu, na ɛde CS gyinapɛn a enye ba.
Ɛdenam peroxide vulcanization nhyehyɛe a wɔfa so no, wɔhyehyɛ carbon-carbon biako nkitahodi, a ɛda nkitahodi ahoɔden a ɛkorɔn adi na ɛko tia mpaapaemu ne recombination wɔ ɔhyew a ɛkorɔn-ɔhyew nhyɛso ase, na ɛnam so tew daa nhyɛso deformation so kɛse.
Aguadi-off no yɛ peroxide{1}}vulcanized nneɛma a ɛko tia nusu a ɛso tew. Eyi gyina hɔ ma kari pɛ a ɛtaa ba wɔ "non-tearability" a wobenya ne "rebound properties" a wɔbɛkɔ so akura mu ntam.
3. Akatua ma nneɛma CS attenuation denam nhyehyɛe nhyehyɛe so
Sɛ wɔayɛ ade no CS boɔ no yie akodu ne honam fam anohyetoɔ (sɛ nhwɛsoɔ no, 30%) a, yɛbɛyɛ dɛn ahwɛ ahu sɛ wɔbɛkɔ so ayɛ nsɔano adwuma wɔ berɛ tenten-mu dwumadie mu?
Esiane sɛ yenim sɛ ɛbɛhwere resilience bi nti, ɛsɛ sɛ yɛde saa adehwere yi ka compression allowance no ho bere a yɛreyɛ groove dimensions no.
Nanso, wontumi mma compression ratio no nkɔ soro daa. Sɛ nhyɛsoɔ dodoɔ no kɔ soro dodo (ɛboro 40%) a, nhyɛsoɔ a ɛwɔ polymer no mu no kɔ soro kɛseɛ, na ɛde mfiri mu mpaapaemu ba molecule nkɔnsɔnkɔnsɔn no mu ntɛm na ɛno nti CS sɛe ntɛmntɛm.
Ɔkwan a etu mpɔn sen biara ne sɛ adansi ho mfiridwumayɛfo ne nneɛma ho mfiridwumayɛfo bɛbom anya groove tolerance a egyina stress relaxation curve-nea ɛnsɛe silicone mudi mu kura anaasɛ entumi nkura sealing pressure ratio a ɛdɔɔso mu wɔ mfe du akyi.
Nsɔano a wɔbɛbɔ no kyerɛ titiriw sɛ wobɛyɛ adamfo ne bere tamfo.
Nokware nsɔano mfiridwumayɛfo mfa n’adwene nsi nsɔano a nsu ntumi nkɔ mu bere a wɔawie nhyiam no nkutoo so.
Wɔn haw no gyina sɛ ebia, mfe abiɛsa, anum, anaa du mpo akyi-wɔ ɔhyew a ɛkɔ soro ne nhyɛso a emu yɛ den a wɔde wɔn ho ahyɛ mu mpɛn pii-molekyul nkɔnsɔnkɔnsɔn no bɛda so ara abata dade no ani denneennen.
Sɛ wowɔ nsɔano a ɛkɔ so twetwe mpɛn pii nanso wuntumi nhu nea ɛde ba, anaasɛ wuhu sɛ nea ɔde nneɛma ma no agyapade pon ahorow no yɛ basaa-nhaw wo ho sɛ wobɛka yɛn adetɔn mfiridwumayɛfo no ho nkɔmmɔ de wo mfonini ahorow ne nhwɛsode ahorow a adi nkogu no adi nkitaho.