Otu ihe eji eme wheel worm nke ejiri n'ụgbọ mmiri . Ihe 34CrNiMo6 maka aro irighiri, ọgwụgwọ okpomọkụ: carburization 58-62HRC. Ihe mgbochi worm CuSn12Pb1 Tin Bronze. Ngwa wiilị worm, nke a makwaara dị ka ihe eji eme worm, bụ ụdị ngwa eji eme ihe na ụgbọ mmiri. Ihe mejupụtara ya bụ worm cylindrical (nke a makwaara dị ka ịghasa) na wiil irighiri, nke bụ ngwa cylindrical nke nwere ezé bepụrụ n'ụdị helical. Akpụkpọ anụ worm na-ejikọta na ikpuru, na-emepụta nnyefe dị nro na nke dị jụụ nke ike site na ntinye ntinye gaa na ntinye mmepụta.