Ko te pakitara puranga secant he momo puranga kua karapotia ki te poka turanga. Ka tapahia, ka āraia te puranga raima whakapakari me te puranga raima noa, ā, ka whakaritea ngā puranga kia hanga he pakitara puranga e hono ana tetahi ki tetahi. Ka taea te whakawhiti i te kaha kutikuti i waenga i te puranga me te puranga ki tētahi taumata, ā, i te mea e pupuri ana i te oneone, ka taea e ia te aukati i te wai, ā, he pai mō te whakamahi i ngā wāhi he tiketike te taumata wai whenua me te wāhi whaiti.
Te hoahoa o te pakitara puranga hiraka
I roto i te ariā, nā te mea ka hono tahi te puranga raima papatahi e tata ana me te puranga raima whakapakari hei hanga i te pakitara, ka whai pānga tahi te puranga raima papatahi me te puranga raima whakapakari ina pēhia te pakitara puranga, ina whakapēhia hoki. Mō te puranga raima whakapakari, ka whakanuia e te noho o te puranga raima papatahi tōna pakari piko, ka taea te whakaaro mā te tikanga pakari ōrite i roto i te tatau ina kitea.
Heoi, e whakaatu ana te rangahau i tētahi kaupapa mahi ko te reiti takoha ki te pakari o te puranga raima papatahi he tata ki te 15% noa iho me te putanga mai o ngā kapiti i te raro o te keri. Nō reira, ina nui te nekehanga piko, kāore e taea te whakaaro ki te pakari o te puranga raima papatahi; ina iti te nekehanga piko, ka taea te whakaaro tika ki te takoha pakari o te puranga raima papatahi ina tatauhia te whakarerekētanga o te rarangi puranga, ā, ka taea te whakarea i te pakari o te puranga raima whakapakari ki te tauwehenga whakapai ake i te pakari o te 1.1~1.2.
Te hanganga o te pakitara pou whakarara
Ka whakarewaina te puranga papatahi ki te raima tino pakari i mua i te whakarewanga. Ko te wāhanga e hono ana i te raima o ngā puranga raima papatahi e tata ana ka tapahia e te kaha tapahi o te wiri anga i mua i te whakatakotoranga tuatahi o ngā puranga raima papatahi, kātahi ka ringihia ngā puranga mīti hei whakatutuki i te aukati o ngā puranga tata.
Ko te tukanga hanga o te pakitara pou kotahi-wāhanga e whai ake nei:
(a) Te wiri tiaki kei te tūranga: Ina kaha te pakitara arataki, whakamahia te kerēni hei neke i te wiri ki tōna tūranga, ā, me whakanoho te pokapū o te kaipupuri paipa matua ki waenganui o te kōhao pakitara arataki.
(b) Te hanganga o te kōhao puranga kotahi: Mā te pēhi i te wāhanga tuatahi o te rango tiaki (te hohonutanga o te 1.5m ~ 2.5m), ka tangohia e te peere pewa te oneone mai i te rango tiaki, ka hopu i te oneone me te pēhi tonu ki raro kia pēhia rawatia te wāhanga tuatahi ki roto (ko te tikanga ka waiho he 1m ~ 2m ki runga i te whenua hei whakahaere i te hononga o te rango) kia kitea ai te poutū. I muri i te whakamātautau, ka honoa te rango tiaki tuarua, ā, ka pērā tonu te huringa kia tae ra ano te pēhanga ki te teitei o raro o te puranga hoahoa.
(c) Te hiki i te whare herehere maitai: Mō te pou B, me whakatakoto te whare herehere whakapakari i muri i te tirotiro i te kōhao. I tēnei wā, me tika te teitei o te whare herehere whakapakari.
(d) te werohanga raima: Mena he wai kei roto i te kōhao, me whakamahi i te tikanga werohanga raima i raro i te wai; ki te kore he wai i roto i te kōhao, whakamahia te tikanga whakapūnga kōhao maroke, me te aro ki te wiri.
(e) Te kukume i te pahu ki roto i te puranga: i a koe e ringihia ana te raima, unuhia te rango tiaki, ā, kia tūpato kia ≥2.5m te raro o te pahu tiaki i raro i te mata raima.
Ko te tukanga hanga rarangi puranga penei:
Mō tētahi rarangi puranga ārai, ko te tukanga hanga ko A1→A2→B1→A3→B2→A4→B3, ā, pērā tonu.
Ngā tohu matua mō te raima:
Hei whakatau i te wā whakaroa o te raima o te puranga A, me tatau te wā whakaroa o te raima o te puranga A e ai ki te tātai e whai ake nei i muri i te whakatau i te wā t e hiahiatia ana mō te hanganga puranga kotahi o ngā puranga A me B:
T=3t+K
Tātai: K — wā rahui, ko te tikanga he 1.5t.
I te tukanga o te hanganga kōhao o te puranga B, nā te mea kāore anō kia tino totoka te raima o te puranga A, ā, kei te rere tonu i te āhua A, ka tere pea ki roto i te kōhao o te puranga B mai i te hononga o te puranga A me te puranga B, ka hanga he "puku paipa". Ko ngā mahi whakakore ko:
(a) Whakahaeretia te hinganga o te raima o te puranga A <14cm.
(b) Me whakauru te anga kia 1.5m te iti rawa i raro i te raro o te kōhao.
(c) Mātakihia mēnā ka totohu te mata o runga raima o te pou A i te wā tonu. Mēnā ka kitea he totohu, me mutu tonu te keri i te pou B, ā, i te pēhitanga o te rango tiaki ki raro i te nui e taea ana, whakakīia te oneone, te wai rānei ki roto i te pou B (tauritehia te pēhanga raima o te pou A) kia mutu rā anō te "puku paipa".
Ētahi atu mehua:
Ina tūtaki ki ngā arai o raro whenua, nā te mea he anga rino te pakitara puranga hiako, ka taea e te kaiwhakahaere te hiki ake i te kōhao hei tango i ngā arai ina whakatauhia he haumaru te taiao.
Ka taea te tango ake i te whare maitai kua whakatakotoria ina hutia ake te anga puranga ki runga. Ka taea te whiriwhiri i ngā mahi ārai hei whakaiti i te rahi o te konganuku raima o te pou B, ka taea rānei te whakapiri i tētahi pereti maitai angiangi he iti ake i a ia anō ki raro o te whare maitai hei whakanui ake i tōna kaha ārai-mānu.
I te wā e hangaia ana te pakitara puranga secant, kaua e whakaarohia noa te whakahaere puhoi o te puranga raima papatahi, me aro ki te whakaritenga o te wā hanga o te puranga raima papatahi me te puranga raima whakapakari e tata ana, engari me whakahaere hoki te nekehanga poutū o te puranga, kia kore ai e taea te hanga i te puranga raima whakapakari nā te nui rawa o te tipu o te kaha o te puranga raima. Nā te mea he nui te peka poutū o te puranga raima papatahi kua oti, ka hua ake te āhua o te pānga hononga ngoikore ki te puranga raima whakapakari, tae noa ki te turuturu o te poka turanga, kāore e taea te aukati i te wai me te pakaru. Nō reira, me whakarite he whakaritenga tika mō te hanganga o te pakitara puranga secant, me te tuhi i ngā tuhinga hanga hei whakahaere i te hanganga maeneene. Hei whakahaere i te tika o te hanganga poka o te puranga ārai kia tutuki ai ngā whakaritenga o te hoahoa me ngā whakaritenga e pā ana, me whakamahi te tukanga katoa o te whakahaere tika o te hanganga poka. Ka taea te whakairi i ngā pou rārangi e rua ki runga i te mīhini hanga puranga hei whakahaere i te poutū o te pakitara o waho o te rango tiaki tonga-raki me te rawhiti-uru, ā, ka taea te whakamahi i ngā clinometer e rua hei tirotiro i te poutū o te poka. Me whakatika me te whakatikatika i te wā e kitea ai he hapa.
Pērā i te hanganga o te pakitara tonu o raro whenua, mō te hanganga o te pakitara puranga whakakīkī katoa, me hanga hoki he pakitara ārahi i mua i te keri i te puranga, kia tutuki ai te mana whakahaere o te tūranga papatahi o te puranga ārai kua keria, ā, hei tūāpapa mō ngā mīhini hanga hei ārai i te hinganga o te kōhao, kia tika ai te anga o te pakitara puranga whakakīkī, kia maeneene ai te mahi a te keri whakakīkī katoa. Ka kitea ngā whakaritenga hanganga o te pakitara ārahi i roto i ngā whakaritenga e tika ana mō te pakitara diaphragm raro whenua.
Wā tuku: Whiringa-ā-rangi 17-2023