Ifomula yesichumisi ikakhulu yenziwe ngesichumisi esingaphiliyo, isichumisi esiphilayo, iminerali njalo njalo.Isichumiso se-inorganic kwisichumiso esihlanganisiweyo, esifana ne-urea sigqwesa ukungunda kwesangqa, umngxuma wokufa weringi kunye nomngxuma wangaphakathi wekhowuni unxitywe kabukhali yiminerali, ngoko ke imathiriyeli yokungunda kwesangqa kufuneka ikhethwe yintsimbi engenasici X46Cr13.Isichumisi esidityanisiweyo sokufa kwentsimbi sikhulu ngokubanzi, siphakathi kwe-3.0-6.0mm, ngenxa ye-coefficient enkulu yokukhuhlana, umngxuma kunzima ukuwukhupha.