Blow molding yɛ mfiridwuma a wɔde di dwuma kɛse wɔ plastic nneɛma a wɔyɛ mu, titiriw na wɔde yɛ plastic afã horow a ɛyɛ tokuru te sɛ plastic nkotoku, nkuku, ne kar afã horow. Adeyɛ nhyehyɛe no fa anammɔn atitiriw anan ho titiriw: nneɛma a wɔde yɛ nneɛma a wɔde yɛ adwuma, extrusion anaa injection preforming, blow molding, ne post-processing.
Nea edi kan no, wɔ bere a wɔresiesie nneɛma a wɔde yɛ nneɛma no, ɛsɛ sɛ wogyina nneɛma a wɔde yɛ adwuma no ahwehwɛde so paw plastic resin a ɛfata. Nhwɛso ahorow a wɔtaa yɛ ne polyethylene (PE), polypropylene (PP), ne polyethylene terephthalate (PET). Wɔtaa de nneɛma a wɔde yɛ no ka drying system ho wɔ pellet kwan so de yi nsu fi mu na wɔhwɛ hu sɛ nwene no yɛ papa.
Nea edi hɔ ne preforming stage, a wɔakyekyɛ mu titiriw ayɛ no akwan abien: extrusion blow molding ne injection blow molding. Wɔ extrusion blow molding mu no, wɔma plastic pellets yɛ hyew na wɔyow wɔ extruder mu na afei wɔde fa kurukuruwa die mu de yɛ tubular parison (a wɔtaa frɛ no "preform"). Wɔ injection blow molding mu no, wɔde injection molding kwan no di kan yɛ parison no na wɔde hyɛ blow mold mu.
Blow molding ne ade titiriw a wɔyɛ. Bere a wɔma parison no yɛ hyew kodu ɔhyew a wɔpɛ akyi no, wɔde mframa a wɔahyɛ no den gu parison no mu, na ɛma ɛne nkuku no afasu no hyia na ɛtrɛw kɔ sɛnea ɛte. Afei nkuku no onwini nhyehyɛe no yɛ adwuma, na ɛma plastic no yɛ den ntɛmntɛm na ɛyɛ den. Afei nkuku no bue, na wɔtow ade a wɔawie no fi mu. Saa adeyɛ yi hwehwɛ sɛ wɔhwɛ ɔhyew, nhyɛso, ne bere a ɛma onwini so pɛpɛɛpɛ na ama ɔfasu no mu duru yɛ pɛ na ne kɛse agyina pintinn.
Awiei koraa no, post-processing ba, a nea ɛka ho ne trimming, flash removal, printing, ne labeling, de hwɛ sɛ ade no di afɛfɛde ne dwumadie ahwehwɛdeɛ nyinaa ho dwuma. Nneɛma bi a ɛhwehwɛ pii nso hwehwɛ sɛ wɔsɔ hwɛ, te sɛ ɔfasu no mu duru susuw ne nsɔano sɔhwɛ, na ama wɔahwɛ ahu sɛ ɛne gyinapɛn ahorow a ɛfa nneɛma pa ho hyia.
Blow molding nhyehyɛe no, esiane sɛnea ɛyɛ adwuma yiye, ɛyɛ mmerɛw, na ɛfata ma nneɛma akɛse-yɛ nti, di dwuma titiriw wɔ nnwuma te sɛ nneɛma a wɔde kyekyere nneɛma, aduruyɛ, ne kar ho. Wobetumi ama nneɛma a wɔyɛ no yiye ne sɛnea wɔyɛ no yiye no atu mpɔn kɛse denam nhyehyɛe no ho nhyehyɛe ne nkuku nhyehyɛe a wɔbɛma ayɛ papa so.
