CN102151697A - Large-specification steel rod diameter fixing hole pattern and diameter fixing process - Google Patents

Abstract

The invention discloses a large-specification steel rod diameter fixing hole pattern and a diameter fixing process. The height H0 of the diameter fixing hole pattern is D, the radius R of a main circular arc is 0.5D, the centre angle a of the main circular arc is 100 DEG, and the radius R1 of a transitional circular arc is 0.15D, wherein D is the hot diameter of a finished steel rod. In the diameter fixing process comprises, an octagonal ingot of which the diameter H2 of an inscribed circle of the cross section is equal to D+160 to 200 millimeters is selected as a raw material, wherein D is the hot diameter of the finished steel rod and; and the diameter fixing hole pattern is used for rolling diameter fixing. The process comprises the following process steps: rolling an eight-edge-prism-shaped steel blank reciprocally for four times till the height H1 of the finished product, wherein the rolling reduction per time is less than or equal to 50 millimeters; and turning the blank rolled in by the first step at 90 DEG, feeding the blank to rollers, rolling reciprocally for 4 times, and obtaining a finished product, wherein the rolling reduction per time is less than or equal to 40 millimeters. The process has the advantages that: the total rolling times are reduced; the rolling time is short; forming can be accomplished with one time of heating; and the rolling is stable.

Description

Large-size round steel sizing pass and fixed diameter process

Technical field

The present invention relates to a kind of large-size round steel sizing pass and fixed diameter process, belong to the metallurgy industry technical field of steel rolling.

Background technology

The level of production of major diameter high-alloy seamless steel pipe is to weigh the important indicator of a national steel industry integral production level, the quality and the price of the raw material that production major diameter high-alloy seamless steel pipe is required----major diameter round steel are one of the key factors of the level of production of restriction major diameter high-alloy seamless steel pipe.At present, for various reasons, the domestic major diameter round steel that the high-quality cheapness still can not be provided.

The approach that the large diameter round steel of China obtains mainly is casting and forging, and the maximum specification of present domestic continuous casting billet is a Φ 800mm round steel, and the Foundry Production of the above round steel of Φ 800mm remains blank out.And the major diameter round steel that traditional handicraft is produced more than the Φ 800mm is to adopt forging method, generally needs to heat twice, the first fire time bar hold, chamfered edge, back-end crop at least; Second fire pulls out, falls circle, crop.And the round steel that passes through the forging acquisition is with high costs and dimensional accuracy is not high, need carry out machined, and stock utilization is low, usually is used to the occasion of having relatively high expectations.Stand in the height of optimizing whole steel industry product structure, improve enterprise's competitiveness in the international market, the round steel production that solves more than the Φ 800mm is imperative.

Summary of the invention

The object of the present invention is to provide a kind of large-size round steel sizing pass and fixed diameter process.This new technology only need heat once, just can produce the large-scale round steel with certain extension, extend to be meant that the rolling preceding initial cross-section of steel ingot amasss and the ratio of finished product sectional area, and be a quantizating index of steel billet deformation extent.

The single-orifice type that large-size round steel sizing pass of the present invention is high roll gap, pass circular arc cornerite is little, its shape as shown in Figure 1, wherein: pass overall height H 0=D; Main arc radius R=0.5D; The angle a=100 of main center of arc °; Transition arc radius R1=0.15D, wherein D is the hot diameter of finished product round steel.Its characteristics are: rolled piece turns over behind 90 ° of the steel when rolling, and the every face of the degree of overlapping of circular arc has about 10 °, can guarantee that transition is mild between circular arc.

Large-size round steel fixed diameter process of the present invention is: selecting the cross section inscribed circle diameter for use is that the anistree ingot of H2=D+160～200mm is as raw material, wherein D is the hot diameter of finished product round steel, utilize the described large-size round steel sizing of claim 1 pass to be rolled sizing, mainly comprise following processing step:

The first step, rolling eight prismatic steel billets, drafts are≤the 50mm/ passage that round rolling 4 passages back and forth are rolled down to finished product height H 1;

Second step, will overturn 90 ° through the blank of the rolling formation of the above-mentioned first step, it is rolling to send into roll then, and rolling drafts is≤the 40mm/ passage that round rolling 4 passages are rolled into finished product.

The invention has the advantages that:

1, owing to adopted the design of suitable pass, make that total rolling pass only is 8 roads, and rolling in same pass all the time, do not need to come the travelling backwards steel pass, so rolling time is short, required add showing tremendous enthusiasm time few, once heating is promptly plastic, and is rolling stable.

2, adopt light reduction to be rolled, can guarantee not have and spread, be i.e. steel billet horizontal deflection when rolling.

3, anistree ingot about, about face almost plane all, when nipping stability better, this is very favourable to rolling stability.

4, the pass grooving is shallow, and drafts is little, and this breaker roll utilizes and life cycle of roll improves very favourable.

Description of drawings

Fig. 1 is the structural representation of sizing pass among the present invention.

Fig. 2 is a fixed diameter process process schematic diagram among the present invention.

The specific embodiment

The invention will be further described below in conjunction with the drawings and specific embodiments, can be implemented so that those skilled in the art can better understand the present invention also, but illustrated embodiment is not as a limitation of the invention.

Embodiment one: present embodiment is described to be 20G for producing type of steels, and finished diameter is the Roller Design and the fixed diameter process of the super-large diameter round steel of Φ 1000mm (heat is of a size of Φ 1015mm).

Use roller diameter to be 1500mm in the present embodiment, rotating speed is 10～20rpm, and roll gap is 565～455mm.This pass schedule is referring to accompanying drawing 1, wherein: main arc radius R=515mm; Transition arc radius R1=150mm; Pass overall height H 0=1015mm; The angle a=100 of main center of arc °.

The described fixed diameter process of present embodiment is: the steel billet of selecting eight prism shapes of inscribed circle D=1200mm (heat is of a size of D=1215mm) for use is a raw material, and the sizing process mainly comprises referring to accompanying drawing 2:

The first step, rolling temperature is the steel billet about 1150 ℃, drafts is≤the 50mm/ passage, come and go rolling 4 passages, make blank reach the finished product height, i.e. H1=1015mm is referring to Fig. 2 a, dotted line represents to enter corresponding pass steel billet cross section before, the steel billet cross section when the hatching region representation is finished this step among the figure.Do not spread owing to have when rolling, so width size 1215mm does not change through the rolling back of 4 passages among Fig. 2 a.

Second step, to overturn 90 ° through the blank of the rolling formation of the above-mentioned first step with manipulator, it is rolling to send into roll then, rolling drafts is≤the 40mm/ passage, come and go rolling 4 passages, be rolling to finished size, shown in Fig. 2 b, dotted line represents to enter pass steel billet cross section before, the steel billet cross section when the hatching region representation is finished this step among the figure.

So stability better because the suitable drafts of employing can be avoided spreading in the sizing process, helps improving product circularity when nipping owing to the anistree pass blank pass of employing.

Adopt this new technology to carry out the product size precision height that Φ 1000mm round steel steel rolling sizing comes out, do not need post bake, reduced and add showing tremendous enthusiasmly time, do not need to carry out again machined, saved production cost.Increase substantially stock utilization, reduce production costs, have huge economic benefit and social value.

The above embodiment is the preferred embodiment that proves absolutely that the present invention lifts, and protection scope of the present invention is not limited thereto.Being equal to that those skilled in the art are done on basis of the present invention substitutes or conversion, all within protection scope of the present invention.Protection scope of the present invention is as the criterion with claims.

Claims (2)

1. a large-size round steel sizing pass is characterized in that: pass overall height H 0=D; Main arc radius R=0.5D; The angle a=100 of main center of arc °; Transition arc radius R1=0.15D, wherein D is the hot diameter of finished product round steel.

2. large-size round steel fixed diameter process, it is characterized in that: selecting the cross section inscribed circle diameter for use is that the anistree ingot of H2=D+160～200mm is as raw material, wherein D is the hot diameter of finished product round steel, utilize the described large-size round steel sizing of claim 1 pass to be rolled sizing, mainly comprise following processing step:

The first step, rolling eight prismatic steel billets, drafts are≤the 50mm/ passage that round rolling 4 passages back and forth are rolled down to finished product height H 1;

Second step, will overturn 90 ° through the blank of the rolling formation of the above-mentioned first step, it is rolling to send into roll then, and rolling drafts is≤the 40mm/ passage that round rolling 4 passages are rolled into finished product.

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