Alamarin na Kafa na HDPE don Ajiye a Waje: Mabudin Na Yadda Za A Yi Trench Excavation, Welding, Testing, da Engineering

 

A cikin ƙaramin kofin da aka tsara a daga cikin shekara biyu da suka gabata, ƙaramin gas da aka gudan cikin rani suna da alama ga high-density polyethylene (HDPE). Daga lokacin da polyethylene pipes sune ka fito a amfani da su don gas transmission a shekara ta 1960s, HDPE gas pipes sun zama alama na yanzu don underground natural gas distribution. A yanzu, a North America, Europe, da ƙaramin Asia, wani mahaullin polyethylene mai kyau—PE100—yana cikin ƙaramin kofin da aka tsara da kofin da aka gudan. Wannan alama an samu shi a cikin ƙaramin rani, ba a cikin kofin da aka rubuta ba. Kofin da aka gudan yana bukatar yin amfani da shi tare da amanah da 50 shekara ko karanci a rani mai ruwa da kuma mai kusantar alkali, kuma polyethylene yana da kyau don wannan alama da kuma yana fi dukkan wani mahaullin kofin da aka rubuta. Steel da ductile iron sun kusanta a dukkan rani kuma suna bukatar coatings da kusantar alkali, cathodic protection, da amfani da inspection na farko don yin amfani da su. Amma, HDPE gas pipes ba su da wadannan kuskuren. Suna da amfani da kusantar alkali wanda ya kusanta kofin da aka rubuta, saboda haka, wadansu utilities da suka yi amfani da ISO 4437 da ASTM D2513 suna nuna PE pipes don alama na farko don karamin kofin da aka tsara da kofin da aka gudan.

 

Amincewar mutane da polyethylene ta wuce ƙarfin lalata ta. Ƙungiyoyinsa suna haɗuwa da haɗuwa, ba a haɗa su ta hanyar inji ba. Butt fusion welds bututu sassan cikin wani m, monolithic abu, yayin da electrrofusion cimma wannan sakamako a kan kayan aiki. Saboda haka, haɗin bututun gas na polyethylene mai ƙarfi (HDPE) da aka yi da kyau yana da ƙarfi kamar bangon bututun kansa kuma ba shi da gasket, zaren, ko hatimin inji da zai iya sassautawa, tsufa, ko kuma zubewa cikin lokaci. Shi ya sa masana injiniya suke da'awar cewa idan aka kafa hanyar sadarwa mai ɗauke da iskar gas mai ƙarancin ruwa, ba za a sami ɓarkewar iskar ba. Hakanan kayan aikin yana da abokantaka ga ma'aikata: bututun HDPE na iya lanƙwasawa don dacewa da layin rami da manyan layin layi ba tare da buƙatar ƙarin kayan aiki ba, kuma suna da isasshen sassauci don ɗaukar motsi na ƙasa wanda ya haifar da kwanciyar ƙasa, dusar ƙanƙara, da girgizar ƙasa A hade tare da fasahohin gini ba tare da rami ba kamar hakowa mai kwance, polyethylene ya zama mafi ƙarancin haɗari, mafi ƙarancin hanyar isar da gas ga al'ummomi. Waɗannan halaye huɗu suna bayyana mamayar sa: juriya lalata, haɗin haɗin haɗin da ba shi da ɓarna, sassauci, da juriya ga matsin ƙasa. A cikin surori masu zuwa, za mu bincika waɗannan halaye ɗaya bayan ɗaya daga hangen nesa na aikace-aikacen aiki: abin da suke nufi a cikin rami, yanayin ƙasa, da kuma a cikin shekaru 50 na sabis na gaba.

 

Me ya sa a amfani da kwayoyin HDPE (high-density polyethylene) a yanzu don samun gas na nazarin da ke cikin ƙasa? ?

A cikin wani lokaci na baya da saukarwa, masu amfani da gas suka bukata biyu waɗanda suka iya shirin zaman lafiya ta hanyar kofin gaba: tushen abu da karamin kofin. Kofin na PE (polyethylene) suka raba a cikin karamin su daga cikin "Karamin Yanzu Da Amince" (MRS), wanda ke nuna yadda ya iya kare tsarin kofin a 50 shekara a 20°C (sannan a cikin ISO 9080). PE80 yana da MRS na 8.0 MPa, amma PE100 yana da 10.0 MPa; don haka, a cikin karamin kofin daya, kofin na gas na PE100 SDR11 suna da alaƙa mai ƙarfi da kuma kariya mai ƙarfi ga kofin da ya zama ƙarfi a cikin kofin na gas da aka saba, wanda ke ƙarfi a cikin kofin na gas da aka saba—wanda ke ƙarfi a cikin kofin na gas da aka saba. Don haka, kofin na gas na PE100 SDR11 suna zama alaƙa na farko a cikin kofin na gas na wasu kofin da aka saba, amma PE80 yana ba da amfani a cikin kofin na gas na farko da aka saba. Tanan kofin da SDR (standard dimension ratio) suka iya koyon kofin na gas: Yurupi yana amfani da ISO 4437/EN 1555, amma Amurka ta Arewa yana amfani da ASTM D2513.

 

Don tsarin watsawa da rarraba gas na karkashin kasa, yanke shawara na biyu shine kaurin bango. SDR (Rashin Yanayin Yanayin Yanayin Yanayi) an bayyana shi ne rabo daga diamita na waje zuwa kaurin bango, kuma ana lissafin nauyinsa ta amfani da tsari: MOP = 2 × MRS / (C × (SDR − 1)), inda MOP shine iyakar aiki da kuma C shine jimlar amfani. Masana'antar gas yawanci tana amfani da C = 2, saboda haka matsin lamba na bututun gas PE100 SDR11 yana da kimanin 10 bar; yayin da bututun SDR17 ko SDR17.6 (mafi ƙanƙanta ganuwar, ƙananan farashi) sun dace da watsawa da rarraba ƙananan matsin lamba. Ƙari ga haka, dole ne a yi la'akari da abubuwa biyu da ake yin gyara a kai a kai a cikin talifofi na gaba ɗaya. Na farko shine ƙirar ƙira, wanda ke sarrafa ƙarfin ƙarfin a kusan rabin ƙarfin shekaru 50 (C = 2, kuma Dokar 49 CFR ta Amurka ta 192 ta ƙayyade iyakar 0.4) don hana jinkirin yaduwar fashewa a cikin shekarun da suka gabata na aiki. Na biyu, akwai rage zafin jiki, tun da duk ƙididdigar suna dogara ne akan 20 °C: lokacin da zafin jiki ya fi 20 °C, dole ne a ninka MOP ta hanyar rage yawan yanayin da aka bayyana a ISO 4437-5 (har zuwa 40 °C); idan darajar ragewa ta fi ƙasa da buƙatar aiki, dole ne a zaɓi Don manyan bututun matsakaici, takamaiman takamaiman yakamata ya zama bututun gas PE100 SDR11, kuma an tabbatar da SDR, ƙirar ƙira, da rage zafin jiki bisa ga takamaiman takamaiman bayanai.

 

Kontrolin kwalitas a lokaci na gas na HDPE ?

Yaya za a iya amfani da saftin lokaci na gas na HDPE? Kontrolin kwalitas yana kara gamsarwa akan hudu babban abubuwan da suka zama maimakon fuskantar: kuma kuma, kuma kuma, tsarin ƙarfi, da amsa na SDR (Standard Draw Reduction). Wadannan abubuwa zasu iya dacewa ta hanyar amfani da shirin da ke cikin kai.

Kuskuren da ayyukan kuma yadda ake saukarwa suka kashe duniya. Bayanin saukarwa mai zuwa: Yadda ake saukarwa ba tare da tsarin bayanin da aka gano ba zai iya zama wani abu da ke nuna cewa ya dace, amma ya kashe ne saboda yadda ake yin saukarwa ta hanyar rarraba; don haka, saukarwa zai shiga cikin tsarin bayanin da aka gano. Kuskarin kofin kofin: A lokacin da ake kuskarwa, kwayoyin da suka dace da kofin kofin na kwayoyin da suka dace zai iya kuskarwa ga kofin kofin; don haka, kwayoyin da suka dace da kofin kofin na kwayoyin da suka dace zai shiga cikin kofin kofin da kuskarwa. Kuskarin kofin kofin: Kofin kofin zai shiga cikin kofin kofin da kuskarwa; kofin kofin zai shiga cikin kofin kofin da kuskarwa. Kuskarin SDR: A lokacin da ake kuskarwa, SDR11 ko SDR17.6 zai shiga cikin kofin kofin da kuskarwa ta hanyar yadda ake kuskarwa. Ta hanyar kuskarwa na kofin kofin, kofin kofin zai shiga cikin kofin kofin da kuskarwa.

 

Kuskarin kofin kofin na HDPE: Kofin kofin na kuskarwa da kuskarwa ba tare da kofin kofin ?

Ya kamata a zaɓi ƙarƙashin ƙwayoyin gas na HDPE da ke cikin ƙarƙashin da ke cikin ƙarƙashin wani abu kamar yadda ya kashe. Karkara mai ƙarƙashin ƙwayoyin da ke cikin ƙarƙashin ya zama mafi kyau don ƙarƙashin ƙwayoyin da ke cikin ƙarƙashin; teknikin karkara mai ƙarƙashin na horizontal (HDD) zai iya tashi karkarar gida da karkarar kudin ba tare biyayen ƙarƙashin. Materiaalin HDPE suna da alaƙa ta hanyar karkara mai ƙarƙashin: kwayoyin da suka daga karkara na heat fusion suna da alaƙa ta hanyar karkara, wanda zai iya tashi karkarar karkarar da kuma zai iya samun karkara mai ƙarƙashin da ba suka daga karkara.

Tarehe	Aikace-aikace
Kuma ta hanyar gurbi na baya	Karkarar da ke cikin ƙarƙashin
Karkara mai ƙarƙashin na horizontal	Tashin karkarar gida, tashin karkarar kudin
Karkara mai ƙarƙashin	Sauran karkara

 

Kafin kofin ya zama shi ne a yankin da ke cikin kofin mai gaba, kuma a sanya kofin na HDPE a cikin hanyar da ke cikin kofin, don haka yanzu ake tsayawa ga yankin da ke cikin kofin. Kofin na gas na yanzu ana saukarwa ta hanyar tashin kofin, kuma teknikin HDD (High-Density Die-Drying) ana amfani da ita lokacin da aka tashi abubuwa da suka daga kofin, amma kafin kofin ya zama shi ne a yankin da ke cikin kofin. Duk wadannan uku hanyoyi suna da alaƙa da ƙarfin HDPE—kamar yadda kofin ya zama mafi kyau da kuma yana da kyakkyawan kofin da ke cikin kofin, kuma ƙarfin da ke cikin kofin ya zama mafi kyau da kuma yana da kyakkyawan kofin da ke cikin kofin—don haka kofin na gas na HDPE ya zama mafi kyau da kuma yana da kyakkyawan kofin da ke cikin kofin lokacin da ke amfani da tashin kofin ko tashin kofin ba.

 

Babban Tambayoyin Da Ake Tambaya A Kofin Na HDPE Ga Gas: Babban Tambayoyin Da Ake Tambaya Daga Masu Ingilishi Da Masu Buyi

Tambaya 1. Wane nisa kofin na HDPE ke amfani da ita a cikin kofin na gas na yankin da ke cikin kofin?

Kwayoyin gas na gaba daya da kwayoyin gas na abokan su ke amfani da kwayoyin polyethylene (PE80 ko PE100) (kamar yadda ake sani, suna daga wani launin kyau ko baki da kwayoyin kyau) kuma su haɗa da standar din ISO 4437/EN 1555 (standar din ASTM D2513 ana amfani da shi a Najeriyar Arewa). Kwayoyin PE100 suna da tsarin yin amfani mai zuwa (MRS) ta 10 MPa kuma suna canja a cikin kwayoyin gas na wasu kwayoyin gas na gaba daya na farko: don hakan, su na da tsarin yin amfani mai zuwa (pressure rating) ta yawa da kuma su na da kariya mai zuwa ga kwayoyin gas na gaba daya na yawa.

Tambaya Na Biyu: Wane SDR (Standard Draw Ratio) ya kamata a amfani da shi a kwayoyin gas na HDPE?

Wannan ya zama a matsayin tsarin yin amfani. Idan tsarin yin amfani na gas C = 2, tsarin yin amfani mai zuwa (pressure rating) na kwayoyin gas na PE100 SDR11 zai kasance ta 10 bar; SDR11 zai dace da kwayoyin gas na gaba daya na yawa da kuma a cikin kwayoyin gas na gaba daya na yawa ba tare da kwayoyin gas na gaba daya. Don kwayoyin gas na yawa, za a iya amfani da kwayoyin gas na SDR17.6 wanda aka fuskanta kwalla da kuma yana da karamin kudada; idan kwalla na kwayoyin gas ya fi 20°C, za a buƙata yin kara karamin tsarin yin amfani (pressure reduction) a cikin standar din ISO 4437-5.

Sawal 4. Za a iya sa’o kwayoyin gasin HDPE ta hanyar alamar daidai?

Ee. Tattalin arziki na sa’o kwayoyin gasin HDPE ta hanyar alamar daidai (HDD) ana amfani da su a yanzu don sa’o kwayoyin gasin HDPE ta hanyar alamar daidai akan kofa, kudun kasa, da kofa na tafarki: kwayoyin suna kawo daga cikin kwayoyin da suka kawo da sa’o ta hanyar thermofusion butt welding sannan suna kawo daga cikin kwayoyin da suka kawo. Kewayoyin suna da kariya wanda ke ba su damar kawo daga cikin kwayoyin da suka kawo; kuma kewayoyin suna da kariya wanda ke ba su damar kawo daga cikin kwayoyin da suka kawo—wanda kewayoyin na steel ba su iya yin ba.

Sawal 5. Shin yana farko bayan butt fusion da electrofusion?

Wadannan biyu hanyoyi zasu iya samun kishin da kishin na wani abu mai tsayi, wanda yana da tsayin kamar tsayin kwalla, ba a bukatar gasket ko threads. Butt fusion ya amfani da heating plate don yanka kwalla da kwalla kuma yin shiga su—wanda ke da alaƙa da kwalla mai tsayi da kwalla na farko, wanda ke cikin zaman lafiya kuma yana da kyau, amma yana bukatar butt fusion machine da masu amfani da su. Electrofusion ya amfani da electric heating wire wanda aka saba da fitting don yanka kwalla a wani wuri—wanda ke da alaƙa da kishin da kishin, rarraba, da aiki a wani wuri da ke ƙarami.