Kodi mitundu ya retarders ndi iti?

Retarders ndi zinthu zowonjezera zomwe zimachepetsa kuyika kapena kuumitsa kwa simenti. Amagwiritsidwa ntchito popanga konkriti komwe kuchedwetsa kumakhala kofunikira, monga nyengo yotentha, kapena kusakanikirana kotalikirapo kapena nthawi yoyika ikufunika. Pali mitundu ingapo ya retarders yomwe ilipo, iliyonse ili ndi zida zake komanso zopindulitsa. Nayi mitundu ina ya retarders:

1. Organic Acids: Ma organic acids monga citric, tartaric, ndi gluconic acid amagwiritsidwa ntchito ngati zolepheretsa zinthu zopangidwa ndi simenti. Amagwira ntchito pochita ndi laimu waulere mu simenti, zomwe zimachepetsa njira ya hydration. Ma organic acid retarders nthawi zambiri sakhala poizoni komanso amatha kuwonongeka, kuwapangitsa kukhala okonda zachilengedwe.
2. Shuga: Shuga monga shuga, sucrose, ndi fructose atha kugwiritsidwanso ntchito ngati zolepheretsa kuzinthu zopangidwa ndi simenti. Amagwira ntchito pomanga pamwamba pa tinthu tating'ono ta simenti, zomwe zimachepetsa njira ya hydration. Ma retarders a shuga nthawi zambiri amagwiritsidwa ntchito limodzi ndi obwezeretsanso ena kuti apereke nthawi yoyendetsedwa bwino.
3. Mchere wa Inorganic: Mchere wa inorganic monga borax, zinc sulfate, ndi sodium silicate amagwiritsidwa ntchito ngati zobwezeretsanso zinthu zopangidwa ndi simenti. Amagwira ntchito popanga filimu yopyapyala pamwamba pa tinthu tating'ono ta simenti, zomwe zimachepetsa hydration. Zoletsa zamchere zamchere nthawi zambiri zimagwiritsidwa ntchito limodzi ndi organic acid kapena shuga retarders kuti apereke nthawi yokhazikika komanso yodziwikiratu.
4. Lignosulfonates: Lignosulfonates ndi ma polima achilengedwe omwe amachokera ku zamkati zamatabwa. Nthawi zambiri amagwiritsidwa ntchito ngati zochepetsera muzinthu zopangira simenti, chifukwa amagwira ntchito pomanga pamwamba pa tinthu tating'ono ta simenti ndikuchepetsa njira ya hydration. Ma retarders a Lignosulfonate nthawi zambiri amakhala othandiza kwambiri mu simenti ya aluminiyamu kuposa simenti wamba ku Portland.
5. Ma Hydroxycarboxylic Acids: Ma hydroxycarboxylic acid monga gluconic ndi citric acid amagwiritsidwa ntchito ngati zolepheretsa zinthu zopangidwa ndi simenti. Amagwira ntchito poyesa ma ayoni a calcium aulere mu simenti, zomwe zimachepetsa kuthamanga kwa madzi. Ma retarders a Hydroxycarboxylic acid nthawi zambiri amagwiritsidwa ntchito limodzi ndi obwezeretsanso ena kuti apereke nthawi yokhazikika komanso yodziwikiratu.
6. Polycarboxylate Ether (PCE) Superplasticizers: PCE superplasticizers amagwiritsidwa ntchito ngati zochepetsera mu ntchito za konkire komwe kuchedwa kwa nthawi kumakhala kofunikira. Amagwira ntchito pomwaza tinthu tating'onoting'ono ta simenti ndikuchepetsa kuthamanga kwamadzi, zomwe zimachepetsa kuthamanga kwa madzi. PCE retarders nthawi zambiri amagwiritsidwa ntchito pamodzi ndi superplasticizers kuti apereke nthawi yokhazikika komanso yodziwikiratu.

Pomaliza, zobwezeretsanso ndizofunikira kwambiri pazida zopangira simenti, chifukwa zimapereka nthawi yokhazikika yoyendetsedwa bwino ndipo zimathandizira kukonza magwiridwe antchito azinthuzo. Mtundu wa retarder womwe umagwiritsidwa ntchito umatengera nthawi yomwe imagwiritsidwa ntchito komanso nthawi yomwe mukufuna kukhazikitsa, komanso zinthu za simenti ndi zina zomwe zimagwiritsidwa ntchito. Posankha mtundu woyenera wa retarder, makontrakitala ndi mainjiniya amatha kuwonetsetsa kuti zida zawo za simenti ndi zamphamvu, zolimba, komanso zikuyenda bwino pakapita nthawi.