JPH0734958B2 - Ring material manufacturing method by ring mill - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a large-diameter ring material used for an aircraft or the like by a ring rolling mill (hereinafter referred to as a ring mill).

"Prior Art" FIG. 1 and FIG. 2 are a plan view and a longitudinal sectional view showing the structure of a general ring mill, in which reference numeral 1 denotes a rotationally driven main roll and 2 denotes a main roll 1. A mandrel that presses the ring material R that is heated red and presses it while pressing, 3 is a centering roll that keeps the ring material R in a perfect circle, 4 is the ring material R
It is an axial roll that adjusts the width by sandwiching from above and below.

When manufacturing ring materials with this equipment, especially for those made of superalloys, glass-based lubricant powder is usually applied to the entire surface of the ring material, and the melted lubricant is used to roll each roll.
It is designed to prevent abrasion of 1, 3, 4 and mandrel 2.

[Problems to be Solved by the Invention] However, in the rolling method described above, the rotation of the ring material R may suddenly stop in rare cases, which makes it impossible to continue the rolling and also causes the ring material R to come into contact with the mandrel. It had a serious drawback that the part was dented and an irreversible deformation occurred.

The present inventors presumed that this problem might be caused by the method of applying the lubricant, attempted detailed experiments, and obtained the following findings.

That is, in the above method, when the mandrel 2 slips on the lubricant film formed on the inner surface of the ring material R,
Since the contact area of the mandrel 2 with the ring material R is small, the mandrel 2 acts as a wiper, and scrapes the lubricant to the front side of the mandrel with the rotation of the ring material R, and forms a mountain M of the lubricant. When this happens, mandrel 2 is no longer on this mountain M
When the lubricant pile reaches a certain size, the pile M is sandwiched between the mandrel 2 and the ring material R, The viscosity suddenly stops the rotation of the ring material R.

"Means for Solving Problems" The present invention has been made to solve the above problems,
When rolling the ring material, a lubricant is applied to the surface of the ring material excluding the contact surface with the mandrel.

Again, an example of the present invention will be described with reference to FIGS. 1 and 2.

After the ring material R that has been heated red is set in the ring mill, the ring mill is operated as usual, and at the same time, the surface of the ring material R excluding the inner peripheral surface with which the mandrel 2 abuts is coated with a lubricant such as a glass-based powder by an injector (not shown) or the like. Spray and apply. The coating amount per unit area at that time may be the same as the conventional amount. Then, after that, the ring mill may be operated as usual to perform rolling.

According to such a ring material manufacturing method, since the lubricant is not applied to the inner surface of the ring material R with which the mandrel 2 abuts, the mandrel 2 does not slip and stop rotating, and the lubricant is not scraped off. The rotation stop of the ring material R as seen in the conventional method does not occur. Therefore,
It is possible to avoid serious troubles such as unrolling and improve work reliability.

The ring mill used in the present invention is not limited to the one shown in the figure, and can be applied to a ring mill for manufacturing a ring material having a different cross-section, which includes a main roll and a mandrel having different cross-sections.

[Advantages of the Invention] As described above, in the ring material manufacturing method using the ring mill of the present invention, the lubricant is applied to the surface of the ring material excluding the inner surface with which the mandrel abuts, and rolling is performed. Lubricants are not scraped up by a trapped mandrel, and unrollable situations such as rotation stop of the ring material can be avoided and work reliability can be improved.

[Brief description of drawings]

FIG. 1 and FIG. 2 are a plan view and a vertical sectional view showing the structure of a general ring mill. 1 ... Main roll, 2 ... Mandrel, 3 ... Centering roll, 4 ... Axial roll, R ... Ring material.

Claims (1)

[Claims] 1. A method for producing a ring material by a ring mill, wherein a peripheral portion of a ring material is sandwiched between a main roll that is rotationally driven and a rotatable mandrel, and the ring material is rolled while being rotated in the circumferential direction. A method for manufacturing a ring material by a ring mill, which comprises applying a lubricant to the surface of the ring material excluding the contact surface with the mandrel during rolling.