The invention discloses a forming device for a seamless outer protective tube for a high-density
polyethylene prefabricated directly-buried
elbow and a forming technology thereof. The forming device is composed of an
elbow pushing
machine, a controller, a plurality of heating sheets, a cooling air tube, a
polytetrafluoroethylene plate tube, a rail, an electric bending
machine and an
elbow clamp, and preheating sheets, a tube top heating sheet, inner arc heating sheets and outer arc heating sheets are connected to a preheating region, a tube top heating region, an inner arc heating region and an outer arc heating region of a tube body respectively; the cooling air tube is arranged on the outer side of the
polytetrafluoroethylene plate tube, and a plurality of air holes are formed in the inner side of the annular
pipe body of the cooling air
pipe; and the electric bending
machine is composed of a rail car, a gear motor, a small gear disc, a large gear disc, a rotating shaft and a clamping sleeve, and the elbow clamp is arranged on the clamping sleeve. One-time stewing and traction forming can be carried out on a
straight tube of the outer protective tube, eno weld joint exists on thesurface of an elbow product, the overall structural strength is high, the service life is long, and the device is suitable for being used for
machining the elbows of the outer protective tube elbowswith various tube diameters.