Abstract: A combined cam shaft assembling method comprises the following steps: A, grinding the outer diameter of a steel pipe (2) to specified precision, and machining an inner hole of a cam sheet (1) and a signal disc to specified precision; B, pre-installing the cam sheet (1) and the signal disc onto the steel pipe (2) according to a specified sequence, distance and angle; C, utilizing a tension part (3) to penetrate through the steel pipe (2), ensuring the steel pipe (2) to be expanded, so as to fix the cam sheet (1) and the signal disc onto the steel pipe (2) and reach a specified torque. The method is carried out through a combined cam shaft assembling device. By adopting the tension part (3) to expand the steel pipe (2), the steel pipe (2) and the cam sheet (1) can be rapidly combined, the cam sheet (1) and the signal disc can be clamped onto the steel pipe (2) in a more reliable manner, and the strength of the entire cam shaft is relatively high.

Abstract: A combined cam shaft assembling method comprises the following steps: A, grinding the outer diameter of a steel pipe (2) to specified precision, and machining an inner hole of a cam sheet (1) and a signal disc to specified precision; B, pre-installing the cam sheet (1) and the signal disc onto the steel pipe (2) according to a specified sequence, distance and angle; C, utilizing a tension part (3) to penetrate through the steel pipe (2), ensuring the steel pipe (2) to be expanded, so as to fix the cam sheet (1) and the signal disc onto the steel pipe (2) and reach a specified torque. The method is carried out through a combined cam shaft assembling device. By adopting the tension part (3) to expand the steel pipe (2), the steel pipe (2) and the cam sheet (1) can be rapidly combined, the cam sheet (1) and the signal disc can be clamped onto the steel pipe (2) in a more reliable manner, and the strength of the entire cam shaft is relatively high.

Abstract: An exemplary camshaft for a high pressure common rail oil pump and a manufacturing method thereof is provided. The method achieves interference assembly between the mandrel and cam piece, and satisfies anti-rotating torque of the cam piece relative to the mandrel while ensuring the surface hardness of the cam piece. The camshaft includes a mandrel and a cam piece arranged on the mandrel. The anti-rotating torque of the cam piece relative to the mandrel is at least 500 NM after the cam piece and the mandrel are connected by interference fit by hot charge practice. Surface hardness of the cam piece 1 is at least HRC58. The method includes performing interference assembly of the cam piece and the mandrel while performing quenching heat treatment on the cam piece, then quickly cooling the cam piece equipped with the mandrel at the cooling stage during the quenching heat treatment.

Abstract: An exemplary camshaft for a high pressure common rail oil pump and a manufacturing method thereof is provided. The method achieves interference assembly between the mandrel and cam piece, and satisfies anti-rotating torque of the cam piece relative to the mandrel while ensuring the surface hardness of the cam piece. The camshaft includes a mandrel and a cam piece arranged on the mandrel. The anti-rotating torque of the cam piece relative to the mandrel is at least 500 NM after the cam piece and the mandrel are connected by interference fit by hot charge practice. Surface hardness of the cam piece 1 is at least HRC58. The method includes performing interference assembly of the cam piece and the mandrel while performing quenching heat treatment on the cam piece, then quickly cooling the cam piece equipped with the mandrel at the cooling stage during the quenching heat treatment.