CN104923755B - Eliminate the anti-circular measure of flat spheroidal graphite cast-iron section bar bulge defect - Google Patents

Abstract

The invention discloses a kind of anti-circular measure eliminating flat spheroidal graphite cast-iron section bar bulge defect, specifically implement according to following steps: step 1: the parameter of the flat spheroidal graphite cast-iron section bar of different size is carried out linear fit；Step 2: according to the parameter processing graphite set of the flat spheroidal graphite cast-iron section bar of different size in step 1；Step 3: process dummy bar head according to the graphite cannula in step 2；Step 4: the dummy bar head that the graphite cannula obtained according to step 2 in cast iron horizontal continuous caster and step 3 obtain completes the production of section bar.The present invention eliminates the anti-circular measure of flat spheroidal graphite cast-iron section bar bulge defect and efficiently solves the bulge defect of flat spheroidal graphite cast-iron section bar on the premise of not reducing production efficiency.

Description

Eliminate the anti-circular measure of flat spheroidal graphite cast-iron section bar bulge defect

Technical field

The invention belongs to cast iron horizontal continuous caster technical field, be specifically related to a kind of flat spheroidal graphite cast-iron section bar bulge that eliminates and lack The anti-circular measure fallen into.

Background technology

Cast iron horizontal continuous caster is to use special production line, by horizontal continuous-casting method, produces the one of cast iron profile material A whole set of technology.The cast iron profile material history producing and applying only more than two decades at home.During this, rapid with demand in production capacity While expansion, production technology is also constantly improving.Nowadays, domestic have family of professional production enterprise more than ten, defines annual output number The ability of ten thousand tons of cast iron profile materials, can produce the cast iron profile material of all kinds (such as Ductile iron bar, gray iron section bar, alloy cast swage Material etc.), the section bar produced can be that multiple prismatic shape is (such as circular, square, rectangle, hexagon, semicircle, Flos Mume Shape etc.), the length of section bar is changeable according to the demand of user.The cast iron profile material produced by horizontal continuous casting process has one Arrange the feature the most excellent than common foundry goods, such as: there is no the casting flaws such as shrinkage cavity and porosity, sand holes, pore；Crystal grain is tiny, group Knit densification；There are more preferable mechanics, mechanical performance etc..Cast iron profile material has become the engineering material that machine industry is important, and Its application is still continuing expansion.

In cast iron profile material, having the flat type material of a class square-section, it approximates with its shape except being suitable for being processed into Outside part, in terms of making hydraulic part, there is highly important application.But, production finds, such section bar is prone to produce " drum Tripe defect ", it may be assumed that the flat horizontal surface generation tympanites of section bar and protruding so that the more satisfactory state of shape and size of section bar creates bright Significant difference is different, this phenomenon, especially prominent in spheroidal graphite cast-iron section bar.

Summary of the invention

It is an object of the invention to provide a kind of anti-circular measure eliminating flat spheroidal graphite cast-iron section bar bulge defect, solve existing There is the bulge deformation problem that technology is difficult to avoid that when producing rectangle spheroidal graphite cast-iron.

The technical solution adopted in the present invention is, eliminates the anti-circular measure of flat spheroidal graphite cast-iron section bar bulge defect, specifically Implement according to following steps:

Step 1: the parameter of the flat spheroidal graphite cast-iron section bar of different size is carried out linear fit；

Step 2: according to the parameter processing graphite set of the flat spheroidal graphite cast-iron section bar of different size in step 1；

Step 3: process dummy bar head according to the graphite cannula in step 2；

Step 4: the dummy bar head finishing type that the graphite cannula obtained according to step 2 in cast iron horizontal continuous caster and step 3 obtain The production of material.

The feature of the present invention also resides in:

In step 1, the parameter to the flat spheroidal graphite cast-iron section bar of different size carries out linear regression fit, regression forecasting side Cheng Wei:

C=-0.046a-5.62d+0.052ad+7.002,

Wherein, d=a/b is the ratio of width to height of section bar,

A is the nominal width of flat spheroidal graphite cast-iron section bar,

B is the nominal height of flat spheroidal graphite cast-iron section bar,

C=s-b is the bulge amount of flat spheroidal graphite cast-iron section bar,

S is the bulge height average of the flat spheroidal graphite cast-iron section bar of every kind of specification,

Bulge height is the peak that sticks out of the flat spheroidal graphite cast-iron section bar distance to lower surface.

According to step 2 processing graphite set, design parameter is:

The shrinkage factor taking spheroidal graphite cast-iron is 1%,

The width of graphite cannula cavity

The height of graphite cannula cavity

The upper surface sunken arcs of the graphite cannula cavity maximum normal distance away from upper surface

The radius R corresponding to upper surface sunken arcs of graphite cannula cavity₁Meet:

${R_1}^2={H_1}^2+{\left(\frac{a_1-e_1\×2}{2}\right)}^2,$

Wherein,

H₁=R₁-h₁,

e₁The length of wherein one end for the non-recessed portion of upper surface of graphite cannula cavity.

Processing dummy bar head according to step 3, design parameter is:

The width a of dummy bar head₂=a₁-1,

The height b of dummy bar head₂=b₁-0.5,

Radius R corresponding to dummy bar head upper surface sunken arcs₂=R₁,

Dummy bar head upper surface sunken arcs maximum normal distance h away from upper surface₂=h₁,

e₂For the length of wherein one end of the non-recessed portion of upper surface of dummy bar head, e₂=e₁-0.5。

The invention has the beneficial effects as follows: on the premise of ensureing production efficiency, effectively eliminate bulge defect, not only make cast iron The technical merit of horizontal casting is further enhanced, it is also possible to make Producer increase economic efficiency, and helps user to obtain more Preferably section bar, decreases the allowance of section bar.

Accompanying drawing explanation

Fig. 1 is the shape appearance figure in kind of the bulge defect of flat spheroidal graphite cast-iron section bar；

Fig. 2 is the schematic cross-section of the bulge defect of flat spheroidal graphite cast-iron section bar；

Fig. 3 is graphite cannula cross sectional representation；

Fig. 4 is the schematic diagram of graphite cannula cross section of the present invention and sunken arcs position relationship；

Fig. 5 dummy bar head cross sectional representation；

Fig. 6 is the section bar pictorial diagram using the inventive method to produce.

Detailed description of the invention

The present invention is described in detail with detailed description of the invention below in conjunction with the accompanying drawings.

The present invention eliminates the anti-circular measure of flat spheroidal graphite cast-iron section bar bulge defect, specifically implements according to following steps:

Step 1: the parameter of the flat spheroidal graphite cast-iron section bar of different size is carried out linear fit

It is illustrated in figure 1 the shape appearance figure in kind of the bulge defect of flat spheroidal graphite cast-iron section bar, it can be seen that bulge is exactly type Material middle part on flat direction raises up.The difference of the thickness of slab width face central protuberance and edge thickness, bulge amount, weighs according to this Amount bulge deformation degree.

Being illustrated in figure 2 the schematic cross-section of the bulge defect of flat spheroidal graphite cast-iron section bar, in figure, a is flat spheroidal graphite cast-iron The nominal width of section bar, b is the nominal height of flat spheroidal graphite cast-iron section bar.For the spheroidal graphite casting of existing different size in producing Swage material, the distance (i.e. bulge height) of the peak sticked out with vernier caliper measurement section bar to lower surface, every kind of specification Spheroidal graphite cast-iron section bar all measures five, and measured value is denoted as s respectively₁、s₂、s₃、s₄、s₅.Take s₁、s₂、s₃、s₄、s₅Meansigma methods for drum Tripe height average s, deducts the nominal height b in section bar cross section by bulge height average s, just obtains bulge amount c=s-b of section bar, Obtain the ratio of width to height d=a/b in section bar cross section.Disposal data, obtains table 1:

The parameter list of table 1 all size section bar

Data in table 1 are carried out regression fit, obtain following regression prediction equation:

C=-0.046a-5.62d+0.052ad+7.002.

Step 2: processing graphite set

As Fig. 3 (a) show the cross sectional representation of existing graphite cannula, it is horizontal that Fig. 3 (b) show graphite cannula in the present invention The schematic diagram in cross section, comparison diagram 3 (a) and Fig. 3 (b) understand, and when processing the graphite cannula of crystallizer, need the graphite of script rectangle Set pocket machining becomes the shape that its excess-three limit recessed, top is constant.Size (nominal width a, nominal according to section bar to be produced B) and regression prediction equation, draw bulge amount c of section bar, it is then determined that the width a of graphite cannula cavity₁, highly b₁And stone The upper surface sunken arcs of ink set cavity maximum normal distance h away from upper surface₁, concretely comprise the following steps:

In the production process of section bar, molten iron is injected casting ladle by melting stove, then injects holding furnace by casting ladle, every one section Time injects a certain amount of molten iron to holding furnace.In this case, the molten iron temperature in holding furnace is not constant, molten iron Temperature is gradually lowered over time, until adding the molten iron of next casting ladle.When the molten iron temperature in holding furnace is higher, solidification speed Rate is relatively slow, goes out the strand layer after crystallizer relatively thin, and the degree causing section bar top to raise up is bigger；When the molten iron in holding furnace When temperature is relatively low, freezing rate is very fast, goes out the strand layer after crystallizer thicker, and the degree that section bar top raises up has subtracted Weak.Therefore, it is different from the degree of crystallizer out rear section bar top epirelief, in order to prevent section bar from the most recessed feelings occurring Condition, Wo Menqu:

Fig. 4 show the schematic diagram of graphite cannula cross section of the present invention and sunken arcs position relationship, takes the receipts of spheroidal graphite cast-iron Shrinkage is 1%, due to section bar to be produced nominal width a, nominal height b it is known that so:

The width of graphite cannula cavity

The height of graphite cannula cavity

By the width a of graphite cannula cavity₁, the upper surface sunken arcs maximum normal distance away from upper surface of graphite cannula cavity h₁, the radius R corresponding to the upper surface sunken arcs of graphite cannula cavity is drawn according to Pythagorean theorem₁Meet:

${R_1}^2={H_1}^2+{\left(\frac{a_1-e_1\×2}{2}\right)}^2$

Wherein,

H₁=R₁-h₁,

e₁The length of wherein one end for the non-recessed portion of upper surface of graphite cannula cavity.

Step 3: processing dummy bar head

Generally dummy device is combined by two sections, enters a section in crystallizer die cavity and is referred to as dummy bar head, and another section claims For dummy bar.During processing dummy device, first process rectangle dummy bar head (shown in cross section such as Fig. 5 (a)), then by rectangle Dummy bar head is further processed into the constant shape in its excess-three limit recessed, top (cross section such as Fig. 5 (b) shown in), dummy bar head cross-section Face size is depending on section bar transverse section, and design parameter is:

The width a of dummy bar head₂=a₁-1,

The height b of dummy bar head₂=b₁-0.5,

Radius R corresponding to dummy bar head upper surface sunken arcs₂=R₁,

Dummy bar head upper surface sunken arcs maximum normal distance h away from upper surface₂=h₁,

e₂For the length of wherein one end of the non-recessed portion of upper surface of dummy bar head, e₂=e₁-0.5。

Step 4: according to the size of section bar to be produced, by the parameter of the graphite cannula cavity that step 2 obtains, by step 3 The parameter of the dummy bar head obtained, makes corresponding crystallizer graphite cannula and dummy bar head device, finishing type in cast iron horizontal continuous caster The production of material, has been eliminated the section bar of bulge defect.

Embodiment

The width a=180mm of spheroidal graphite cast-iron section bar to be processed, highly b=50mm.

Step 1: linear fit

Data in table 1 are carried out regression fit, obtain following regression prediction equation:

C=-0.046a-5.62d+0.052ad+7.002

Step 2: processing graphite set

Known section bar width a=180mm, highly b=50mm, draws according to regression prediction equation: c=12.18mm, $h_1=\frac{2}{3}c=8\mathrm{mm}.$

Again according to formula $a_1=\frac{a}{1-1\%},b_1=\frac{b}{1-1\%},{R_1}^2={H_1}^2+{\left(\frac{a_1-e_1\×2}{2}\right)}^2,$ H₁= R₁-h₁, e₁=10mm, draws:

a₁=182mm, b₁=50.5mm, R₁=414mm, H₁=396mm.

Step 3: processing dummy bar head

Because a₂=a₁-1, b₂=b₁-1, R₂=R₁, H₂=H₁, h₂=h₁, e₂=e₁-0.5, draw:

a₂=181mm, b₂=50mm, R₂=414mm, H₂=396mm, h₂=8mm, e₂=9.5mm.

According to the above-mentioned data calculated, processing novel graphite cannula and dummy device, and applied aborning, raw As shown in Figure 6, test result indicate that the present invention eliminates the anti-circular measure of flat spheroidal graphite cast-iron section bar bulge defect can for output material object Effectively to solve bulge defect on the premise of not reducing production efficiency.

Claims (1)

1. eliminate the anti-circular measure of flat spheroidal graphite cast-iron section bar bulge defect, it is characterised in that specifically implement according to following steps:

Step 1: the parameter of the flat spheroidal graphite cast-iron section bar of different size is carried out linear fit；

Step 2: according to the parameter processing graphite set of the flat spheroidal graphite cast-iron section bar of different size in step 1；

Step 3: process dummy bar head according to the graphite cannula in step 2；

Step 4: the dummy bar head that the graphite cannula obtained according to step 2 in cast iron horizontal continuous caster and step 3 obtain completes section bar Produce；

In described step 1, the parameter to the flat spheroidal graphite cast-iron section bar of different size carries out linear regression fit, regression forecasting side Cheng Wei:

C=-0.046a-5.62d+0.052ad+7.002,

Wherein, d=a/b is the ratio of width to height of section bar,

A is the nominal width of flat spheroidal graphite cast-iron section bar,

B is the nominal height of flat spheroidal graphite cast-iron section bar,

C=s-b is the bulge amount of flat spheroidal graphite cast-iron section bar,

S is the bulge height average of the flat spheroidal graphite cast-iron section bar of every kind of specification,

Bulge height is the peak that sticks out of the flat spheroidal graphite cast-iron section bar distance to lower surface；

Described step 2 processing graphite set, design parameter is:

The shrinkage factor taking spheroidal graphite cast-iron is 1%,

The width of graphite cannula cavity

The height of graphite cannula cavity

The upper surface sunken arcs of the graphite cannula cavity maximum normal distance away from upper surface

The radius R corresponding to upper surface sunken arcs of graphite cannula cavity₁Meet:

${R_1}^2={H_1}^2+{\left(\frac{a_1-e_1\×2}{2}\right)}^2,$

Wherein,

H₁=R₁-h₁,

e₁The length of wherein one end for the non-recessed portion of upper surface of graphite cannula cavity；

Described step 3 processes dummy bar head, and design parameter is:

The width a of dummy bar head₂=a₁-1,

The height b of dummy bar head₂=b₁-0.5,

Radius R corresponding to dummy bar head upper surface sunken arcs₂=R₁,

Dummy bar head upper surface sunken arcs maximum normal distance h away from upper surface₂=h₁,

e₂For the length of wherein one end of the non-recessed portion of upper surface of dummy bar head, e₂=e₁-0.5。