Under the 58th series of its online exhibition by Indira Gandhi Rashtriya Manav Sangrahalaya, on Thursday presented the 'Sunnapuganugu’— a traditional mechanical device for preparing binding mixture for construction work situated in the open air exhibition, Traditional Technology Park of Manav Sangrahalaya has been presented online with its basic information and photographs and videos.
About this exhibition, Praveen Kumar Mishra, Director, IGRMS said that – Sunnapuganugu is a traditional mechanical device for grinding limestone and preparing a lime binding mixture used for joining bricks and stone in construction works. It is a circular stone track pit built by khondalite stone pieces which is considered to be most suitable for this track pit having heavy weight resistance.
This circular track is 1 feet deep and 1 feet wide and 11 feet in diameter. The main crushing roller sunnapuraiis made of sand stone and weight around 350 to 400 kilograms. This roller has a square shaped hole at the centre for fixing of wooden axle Polukarra. The ingredients required to make this binding mixture are mainly lime powder, sand, sugarcane jaggery, bael fruit (Aegle marmelos), tree silt, Aloe Vera (Aloe barbadensis miller), Harra (Terminelia chebula) etc. The process of mixing the ingredients is completed in two stages. In the first stage, lime powder is prepared in Sunnapubatti furnace for heating limestone. In this furnace, limestone is heated with coal in the ratio of 1:3. Limestone is converted into powder by the energy of coal in the furnace.