A transmission housing is a device used to install the housing structure of the transmission mechanism and its accessories The Sand-cast gearbox housing refers to the gearbox housing manufactured by the sand casting process. Sand casting is a commonly used casting process by mixing sand and binder into a mold and then compacting the sand in the mold to form the desired casting shape. In the manufacture of gearbox housings, the sand casting process can quickly and economically produce complex shaped castings, while also ensuring the accuracy and surface quality of the housings. The sandcast gearbox housing usually has high strength and wear resistance, can withstand the working load of the gearbox, and provides good sealing performance to ensure that the lubricating oil inside the gearbox does not leak.