Thermal bulging process for rectangular stainless steel rolled ring workpieces

Abstract

The invention discloses a thermal bulging process for rectangular stainless steel rolled ring workpieces, which includes steps of primary bulging; primary rotation; secondary rotation; secondary bulging and tertiary bulging. In the primary bulging, a rectangular stainless steel rolled ring workpiece which is treated by thermal rolling is sleeved on the periphery of a preheated bulging block in a bulging machine, and the bulging block squeezes the ring workpiece axially along the inner circumference of the rolled ring workpiece after the bulging machine is started so that the primary bulging is completed, wherein the bulging temperature ranges from 890 DEG C to 950 DEG C, the bulging time ranges from 15s to 25s, the pressure holding time ranges from 7s to 8s, and the deflection ranges from 0.9% to 1.2%. The primary rotation is completed by rotating the rolled ring workpiece along the center axis by 45 degrees. The secondary bulging is completed by processes of the primary bulging, wherein the bulging temperature ranges from 850 DEG C to 910 DEG C, the bulging time ranges from 15s to 25s, the pressure holding time ranges from 9s to 10s, and the deflection ranges from 0.7% to 1 %. The second rotation is completed by rotating the ring workpiece again along the direction the same with that of the primary rotation. The tertiary bulging is completed by the processes of the primary bulging again, wherein the bulging temperature ranges from 800 DEG C to 870 DEG C, the bulging time ranges from 25s to 35s, the pressure holding time ranges from 13s to 15s, and the deflection ranges from 0.5% to 0.8%. The dimensional precision of the rolled ring workpiece can be 1%. to 2%. of the corresponding precision after the rolled ring workpiece is bulged, and the rolled ring workpiece is mainly used for the fields of space navigation and the like.

Description

technical field [0001] The invention relates to a bulging method for a ring, in particular to a thermal bulging method for a stainless steel rectangular ring rolling piece. Background technique [0002] Stainless steel rectangular ring-rolled pieces (referring to the ring-rolled piece with a rectangular longitudinal section) are rolled by the ring rolling mill. Due to the limitation of the rolling process and equipment, the dimensional accuracy is generally not high; only when the shape of the ring-rolled piece is relatively Under the condition of ideal and excellent equipment performance, the dimensional accuracy can reach 3‰~5‰ (three thousandths to five thousandths) of the corresponding size, and the ring rolled parts after rolling are due to the large stress, and the follow-up If the processing process is not well controlled, defects such as warping, deformation and even cracking may easily occur. [0003] The Chinese invention patent specification CN 101367104A publish...

AI Technical Summary

Problems solved by technology

This method does not disclose in detail how to improve the dimensional accuracy of the ring through bulging, but it is generally concluded that the purpose of improving the forming accuracy of the retaining ring can be achieved, that is, this method cannot solve the problem of low dimensional accuracy of the ring rolling in the prior art The problem

Images