jefa baƙin ƙarfe square m bawul

murabba'i mai murabba'i: An shigar da shi a ƙarshen bututun magudanar ruwa, yana da bawul ɗin dubawa don hana ruwa na waje komawa baya. Ƙofar dai ta ƙunshi wurin zama na bawul, farantin bawul, zoben hatimin ruwa da kuma hinge. An raba siffofi zuwa da'ira da murabba'ai

Bawul ɗin hanya ɗaya ce da aka girka a mashigar bututun magudanar ruwa. Lokacin da magudanar ruwan kogin ya zarce bututun fitar da magudanar ruwa, kuma karfin ya fi karfin da ke cikin bututun, sai a rufe bakin kogin kai tsaye don hana kwararar ruwan kogin zuwa cikin bututun magudanar ruwa.