RU97116696A - METHOD FOR RINGING THE RING Billets - Google Patents

Claims (2)

1. The method of rolling ring billets of rectangular cross section from various metal materials on ring rolling mills in a closed gauge (without broadening) in a cold or hot state, including deformation with continuously or discretely increasing compression to obtain the desired specific value of the inner (or outer) diameter, characterized in that the current value of the inner diameter (D _i ) at any stage of the rolling process, up to the final one, is determined by the amount of compression from the ratio

where t is the thickness of the cross section of the original billet, mm;
D is the diameter of the initial workpiece, mm;
Δt _i is the value of the total compression (tt _i ) at this stage of rolling, mm;
t _i is the thickness of the section at this stage of rolling, mm 2. The method according to claim 1, characterized in that the continuous determination of the current value of the inner diameter of the billets of rectangular cross section with recesses (troughs) from the inside and / or from the outside is performed according to the amount of compression from the ratio

where K ₁ and K ₂ are the coefficients of the cross-sectional shape of a given annular blank, determining the degree of its deviation from a rectangular cross-section (type I) without recesses,
the specific values of the coefficients K ₁ and K ₂ depend on the type of cross-section of the annular blanks, namely, on whether there are recesses in the section, and if so, where are they located: inside (type II), outside (type III), or inside and outside (type IV), for ring blanks of the first type (smooth inside and out) K $\genfrac{}{}{0ex}{}{\text{I}}{\text{1}}$ = K $\genfrac{}{}{0ex}{}{\text{I}}{\text{2}}$ = I for ring blanks of the second type (with recesses from the inside)
K $\genfrac{}{}{0ex}{}{\text{II}}{\text{1}}$ = 1-αβ
K $\genfrac{}{}{0ex}{}{\text{II}}{\text{2}}$ = 1-αβ ²
where α and β are the coefficients of the width and thickness of the cross-sections of the second type, representing respectively the proportion of the cross-section in width (h '/ h _i ) and the proportion of the cross-section in thickness (t' / t _i ), comma-recessed,
for ring blanks of the third type (with recesses on the outside)
K $\genfrac{}{}{0ex}{}{\text{III}}{\text{1}}$ = 1-γφ
K $\genfrac{}{}{0ex}{}{\text{III}}{\text{2}}$ = 1-2γφ + γφ ² ,
where γ and φ are the coefficients of the width and thickness of the sections of the third type, which are respectively the fraction of the cross section in width (h '/ h _i ) and the fraction of the cross section in thickness (t' / t _i ), comma-recessed,
for ring blanks of the fourth type (with recesses inside and out)
K $\genfrac{}{}{0ex}{}{\text{IV}}{\text{1}}$ = 1-αβ-γφ
K $\genfrac{}{}{0ex}{}{\text{IV}}{\text{2}}$ = 1-αβ ² -2γφ + γφ ² ,
the values of the coefficients α and γ are always calculated according to the dimensions indicated in the drawing of the given annular blank. In the case (for example, in the initial stage of rolling), when the amount of compression is numerically less than the size of the recess in the cross section (according to the drawing), the values of the coefficients β and φ are determined on the basis that the recess is numerically equal to the size of the compression. In the case when the total compression numerically exceeds the size of the recess in the section (for example, in the final stage of rolling), the calculation of the coefficients β and φ, as well as the coefficients α and γ, is performed according to the dimensions indicated on the drawing. Thus (see Fig. 1, 2, 3, 4):
α = h ′: h _i ; β = t ′: t _i or Δt _i : t _i (for Δt _i <t ′);
γ = h ″: h _i ; φ = t ″: t _i or Δt _i : t _i (for Δt _i <t ″);
where h 'and t' is the height (width) and depth of the recesses from the inside of the section, mm;
h '' and t '' - height (width) and depth of the recesses outside the section, mm;
h _i and t _i - height (width) and thickness of the section at this stage of rolling (the height is constant, and the thickness is continuously decreasing), mm.