CN1274437C - Wedge transverse rolling precision-forming method of hollow wheel axle blank of train - Google Patents

Abstract

The present invention provides a wedge cross-rolling precise forming method for hollow wheel axle blanks of a train. The present invention is characterized in that multiple wedge moulds with three to five pairs of wedges are arranged on a special large-scale wedge cross-rolling mill and used for rolling hollow wheel axle blanks of a train. Seamless steel pipes are heated to 1000 to 1200 DEG C and fed into two multiple wedge moulds with orthokinetic rotation and three to five pairs of wedges for rolling; the shape of a rolling piece in an A-A position in the rolling process is disclosed in a picture 2. Forming angles alpha of mould parameters are from 20 to 34 DEG, and spreading angle beta are from 5 to 12 DEG; such as formula (I), i is wedge sequence number, and that <k> is an included angle of the curved line of the end surface movement amount of the spreading section of the k wedge. Therefore, the rolled length of wheel axles of a train can be simultaneously rolled by the three to five pairs of wedges. The present invention has the advantages that the roll surfaces of the moulds can be obviously saved, the diameters of the moulds are reduced, and the diameters of the moulds for producing the wheel axles of a train can be reduced to 1600 to 1700mm.

Description

A kind of hollow railroad car axle blank cross wedge rolling accurate forming method

Technical field

The invention belongs to axial workpiece plastic forming technology field, a kind of hollow many wedges of railroad car axle blank cross wedge rolling accurate forming method particularly is provided, be applicable to that diameter of phi 180mm is above, length surpasses 2 meters the hollow axial workpiece roll forming of ultra-large type.

Background technology

Railroad car axle is one of three big vital parts (heavy rail, axletree and wheel) of railway construction, belongs to the ultra-large type axial workpiece.Be to realize the train high speed, requirement must alleviate the train own wt, and wherein to be exactly that railroad car axle is made hollow for one of effective measures.

The manufacturing process basic skills of hollow railroad car axle has two kinds: after 1) making the axletree profile with forging method, draw out endoporus with cutting process again; 2) on precise forging machine, get profile with seamless steel pipe.

It is many to produce solid shafting with cross wedge rolling both at home and abroad at present, and it is less to produce hollow shaft; Maximum cross wedge rolling machine mould diameter is φ 1400mm, and the longest in 1200mm with the solid shafting that it is produced, maximum gauge can not rolling hollow railroad car axle below φ 150mm.

If produce hollow railroad car axle with present single wedge cross wedge rolling method, its mould maximum gauge is about φ 3400mm, and the height of milling train will be above 10000mm.Big like this machine and mould, because investment is big, making is difficult, production operation is inconvenient, so can't implement.

Summary of the invention

The objective of the invention is to: a kind of hollow many wedges of railroad car axle blank cross wedge rolling accurate forming method is provided, and it is huge to have solved machinery equipment, and mould is difficult to problems such as manufacturing, has realized producing hollow railroad car axle blank with cross wedge rolling.

The present invention adopts many wedges precision rolling forming technology, and the rolling hollow railroad car axle blank of many wedges mould with 3～5 pairs of wedges is installed on large-scale cross wedge rolling special rolling mill.Seamless steel pipe is heated to 1000～1200 ℃, by the axial admission device send into two in the same way rotation have between many wedges mould (Fig. 1) of 3～5 pairs of wedges and be rolled, A-A position shape of rolling piece is Fig. 2 in the operation of rolling, and the railroad car axle blank of mill product is Fig. 3.The die parameters forming angle is got α=20～34 °, broadening angle and is got β=5～12 °, ${\mathrm{\&beta;}}_i=\mathrm{\&beta;}+\underset{k=1}{\overset{i-1}{\mathrm{\&Sigma;}}}{\mathrm{\&theta;}}_k,$ I is a wedge number, θ _kIt is the angle of the k wedge broadening section movement of the end curve and the roll line of centres.It is simultaneously rolling by 3～5 pairs of wedges that railroad car axle is rolled length like this.Obviously with the rolling comparison of single wedge, can significantly save the mould roll surface and reduce barrel diameter.Therefore, the technology of the present invention is produced railroad car axle and roller diameter can be reduced to φ 1600～1700mm.

The present invention is different with cross wedge rolling train solid axle, rolls hollow shaft and occurs problems such as rolled piece does not rotate easily, so choosing of major parameter is different.

The present invention produces hollow railroad car axle compared with the prior art, and advantage is as follows:

1) with forge cut endoporus after the profile again method relatively: (1) productivity ratio is high more than 8 times; (2) operation of a few deep hole processing; (3) material of saving about 40%; (4) because rolling form accuracy height lacks one roughing operation; (5) production cost can descend about 50% etc.

2) compare with finish forge steel pipe method: (1) is right angle step (finish forge can only be used conical surface transition) because the forming accuracy height also can be shaped, thus both saved material (about 10%), by saving the machined workload; (2) production efficiency is high 4 times; (3) production cost can descend about 15%.

Description of drawings

Fig. 1 is 3 pairs of wedge moulds of a kind of hollow railroad car axle of the present invention expanded view.Be wedge 1, wedge 2 and wedge 3, longer part in the middle of wedge 1 and wedge 2 rolled axles wherein, wedge 3 is combination wedge, two steps of rolled axle limit portion.β ₁, β ₂, β _3-1, β _3-2Be respectively the broadening angle of wedge 1, wedge 2 and combination wedge 3, α ₁, α ₂, α _3-1, α _3-2Be respectively the forming angle of wedge 1, wedge 2 and combination wedge 3.

Fig. 2 is a kind of hollow railroad car axle operation of rolling A-A position rolled piece figure of the present invention.

Fig. 3 is a kind of hollow railroad car axle mill product figure of the present invention.

Fig. 4 is 3 pairs of wedge die drawings of a kind of hollow train RD2 axletree of the present invention.

Fig. 5 is 3 pairs of wedge moulds of a kind of hollow train RD2 axletree of the present invention expanded view.Among the figure, broadening angle β ₁=7 °, β ₂=8.4 °, β _3-1=9.8 °, β _3-2=10.8 °, forming angle α ₁=α ₂=α _3-1=30 °, α _3-2=27 °; h ₁=h ₂=11.605mm, h ₃=16.15mm, h ₄=33.825mm, H ₀=4037.92mm, H ₁=177.81mm, H ₂=355.62mm, L ₁=749.97mm, L ₂=1266.81mm, L ₃=2397.91mm, L ₄=289.62mm, L ₅=269.23mm, L ₆=421.42mm.

Fig. 6 is a kind of hollow train RD2 axletree mill product of the present invention.Among the figure, Dz0=Φ 203mm, Dk=Φ 103mm Dz1=Φ 179mm, Dz2=Φ 170mm, Dz3=Φ 135mm, Lz0=2252mm, Lz1=1198mm, Lz2=489mm, Lz3=285mm, Lz4=232mm, Lz5=308mm.

Fig. 7 is a kind of hollow train RD2 axletree of the present invention.Among the figure, Dc0=Φ 194mm, Dc1=Φ 174mm, Dc2=Φ 165mm, Dc3=Φ 130mm, Dk=Φ 103mm, Lc0=2146mm, Lc1=1204mm, Lc2=471mm, Lc3=273mm, Lz4=220mm.

The specific embodiment

Fig. 4, Fig. 5, Fig. 6 and Fig. 7 are an embodiment of the hollow train RD2 axletree that is shaped, with diameter of phi=203mm, length is 1428mm, the hollow train RD2 axletree seamless steel pipe blank of wall thickness δ=50mm, heating-up temperature is 1050 ℃, send between two the homodromal 3 pairs of hollow train RD2 of wedge axletree moulds by the axial admission device and to be rolled, the mould maximum gauge is φ 1700mm, die drawing is Fig. 4, expanded view is Fig. 5, hollow train RD2 axletree mill product as shown in Figure 6, with the hollow railroad car axle fine finishining of Fig. 6, obtain after the fine finishining hollow RD2 railroad car axle as shown in Figure 7.

Claims (1)

1, a kind of hollow railroad car axle blank cross wedge rolling accurate forming method, it is characterized in that: the rolling hollow railroad car axle blank of many wedges mould with 3～5 pairs of wedges is installed on large-scale cross wedge rolling special rolling mill, seamless steel pipe is heated to 1000～1200 ℃, by the axial admission device send into two in the same way rotation have between the mould of 3～5 pairs of wedges and be rolled, the die parameters forming angle is got α=20～34 °, broadening angle and is got β=5～12 ° ${\mathrm{\&beta;}}_i=\mathrm{\&beta;}+\underset{k=1}{\overset{i-1}{\mathrm{\&Sigma;}}}{\mathrm{\&theta;}}_k,$ I is a wedge number, θ _kBe the angle of the k wedge broadening section movement of the end curve and the roll line of centres, it is simultaneously rolling by 3～5 pairs of wedges that hollow like this railroad car axle is rolled length.

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