TY JOUR TI TECHNOLOGY OF MANUFACTURING AND ASSEMBLAGE OF TRANSPORT MACHINERY HELICAL PROPELLERS KW helical propeller KW multistart helical curved surfaces KW helical grooves KW fabrication method JO Bulletin of Bryansk state technical university AU Serga, G.V. AU Hvostik, E.A. PY 2019 IS 2019 PB Bryansk State Technical University