الفهرس 
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Abstract
A new process for machining of rotat,ionCllly symmetrical workl;ieces can be achieved, if
the rotation of the work piece is combincd with the motion of a rotating milling cutter, i.e. turn-milling process. In the mcan time the cutter is fed longitudin.ally, as in I. Hrning, parallel to the work piece axis. The advantages of this new process include machining of high st.rcllgt.h matcrials, ma.chining of largc awl heavy work pieces, produdion of short. chips and lOllg tool life. Problems of unbalance arising when turning large and heavy workpieces, especially at high cutting speeds, are solved in turn-milling by rotating the workpiece only few revolutions per minutc an(l obtaining the main cutting spec(l from the rotation of the tool. Turn-milling is the :mitable machining process for complete machiniug i.e. performiug all the necessary machiuing operations, turning, drilling, milliug, grinding and t,hread tappiug, from l’Oughiug to finishiug ou a single machine and at it siugle sdtiug. Advantages of complete machining include reduction of lead time, incrcasiug accuracy by reduciug multi set-ups, iU<Teasing metal removal rate and redudioll of produdion costs.
The industrial applicatious of t,hc process include mitchiuillg of the following components, aircraft landing gear leg, calenda.r rolls for paper industry, turbines and valves for power plants and injectioll moulding screws for the plastic industry.
III this research, a theoretical study of the kinematics of the process has hecn carried out.. The results illdica.te that the Hurfacc quality could be improved if eithcr the speed ratio or the lltlluber of teeth increase. Moreover, the productivity may increase if t.he workpiece speed, the depth of cut, the tool diamder increase or the speed ratio, or the number of teeth decrease.
The effect, of the working cOllditions, e.g. feed, depth of cut, speed ratio and re1a.tive positioll between cutter and workpiece axes, on the surface quality has bee11 investigated in ddail.
A portable turn-milling a.tt.achmcnt, was designed a11<l inst.alled Oil the centre litt.1lC’H cross slide. Machining tests were performed for orthogona1 turn-milling, in both the COllcclltric and eccelltric positions, using high speed stec1 shell cnd milling cutters.
The experimental results confirmed the capability of the turu-millillg prOCCHS in machining of rotationally symmetrical workpieces. The following conclusions arc ohta.ilwcl.
(1) F’1~(~cl is Cl (ldenllining factor ill influencing the surface roughncRs, out of r0l1lldncss,