本发明公开一种快速无级调节管材壁厚的挤出成型方法及装置。该装置芯棒及分流锥同心置于模头体及过渡模头体内腔,第一通气孔径向设置在支撑架外环；第二通气孔径向设置在过渡模头体中；第三通气孔轴向设置在分流锥的底部；第四通气孔轴向设置在芯棒中心；第二通气孔通过通气软管与空压机连接,高压压缩空气经上述通气通道顺序进入芯棒外表面和料坯内表面形成高压气垫,改变高压压缩空气的压力及流量来改变高压气垫的厚度,进而实现挤出管材壁厚的快速无级调节。本发明不需要更换芯棒而可无级快速调节挤出管材壁厚,可实现挤出管材壁厚快速、实时、无级调节,同时可有效提升挤出管材壁厚精度及内壁光洁度,增强管材环向力学性能。

The invention discloses an extrusion moulding method and an extrusion moulding device capable of quickly regulating the wall thickness of a pipe in a stepless manner. According to the device, a mandrel and a flow dividing cone are coaxially arranged in the inner cavities of a die head body and a transition die head body; a first ventilating hole is radially formed in the outer ring of a supporting frame; a second ventilating hole is radially formed in the transition die head body; a third ventilating hole is axially formed in the bottom of the flow dividing cone; a fourth ventilating hole is axially formed in the centre of the mandrel; the second ventilating hole is connected with an air compressor through a ventilating hole; high-pressure compressed air enters the outer surface of the mandrel and the inner surface of a material blank through above ventilating channels in sequence to form a high-pressure air cushion, and the thickness of the high-pressure air cushion is changed by changing the pressure and the flow of the high-pressure compressed air, so that quick stepless regulation of the wall thickness of an extruded pipe is realized. According to the extrusion moulding method and the extrusion moulding device capable of quickly regulating the wall thickness of the pipe in the stepless manner, the wall thickness of the extruded pipe can be regulated quickly in the stepless manner without replacing the mandrel; quick, real-time and stepless regulation of the wall thickness of the extruded pipe can be realized; meanwhile, the wall thickness precision and the finish degree of an inner wall of the extruded pipe can be improved effectively; circumferential mechanical properties of the pipe are enhanced.