Plug used in boring machine

A piercing machine and punch technology, applied in metal rolling, manufacturing tools, mandrels, etc., can solve the problem of easy occurrence of melting loss, and achieve the effect of preventing melting loss and reducing the amount of cutting changes.

Inactive Publication Date: 2009-01-14
NIPPON STEEL CORP
View PDF3 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, if it is formed into a tapered shape, the gap IS between the blank and the pierced blank will disappear, and the blank and the tapered portion will contact, so melting loss will easily occur.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Plug used in boring machine
  • Plug used in boring machine
  • Plug used in boring machine

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0075] use Figure 9 , Figure 10 and the punches of the shapes shown in Table 1, the billets were pierced and rolled, and the life of each punch was investigated.

[0076] [Table 1]

[0077]

[0078] The punches of test numbers 1 to 15 and 20 to 24 in Table 1 were formed as Figure 9 In the shape shown, the punches of test numbers 16 to 19 were formed as Figure 10 the shape shown. The symbols (dimensions) of items 7 to 19 in Table 1 and Figure 9 and Figure 10 The notations in are used in pairs. The material of each punch is 1.5% Cr-3% Ni steel (SNCM616 in JIS standard).

[0079] The pierced and rolled billet was formed into a round billet of SUS304 steel with a diameter of 70 mm and an axial length of 400 mm. The billet heated to 1200° C. was pierced and rolled by a piercer equipped with a punch of each test number to form a hollow billet tube with an outer diameter of 76 mm and a wall thickness of 6 mm. The conditions of the punching machine are shown in Table...

Embodiment 2

[0090] The punches of test numbers 20 to 22 did not have a corner radius Rc, but the other shapes and dimensions were the same as the punches of test numbers 7 to 9. Specifically, the punch of test number 20 has the same shape as the punch of test number 7 except for the corner radius Rc. Similarly, the punch of Test No. 21 and Test No. 8, and the punch of Test No. 22 and Test No. 9 have the same shape and dimension except for the corner radius Rc.

[0091] As a result of investigation in Example 1, the number of punches of test numbers 20 to 22 that could be rolled was three or more, similarly to test numbers 7 to 9 . Therefore, in order to investigate the effect of the corner radius, the number of punches that can be rolled was further investigated for the punches of test numbers 7 to 9 and 20 to 22.

[0092] As a result of the investigation, the punches of test numbers 20 to 22 that did not have a corner radius Rc all had melting loss at the adjacent part of the front end ...

Embodiment 3

[0094] The relationship between the spherical shape of the tip portion and the occurrence of melting loss was investigated. Specifically, the number of punches that can be rolled was investigated for punches of test numbers 7 and 11, 8 and 12, and 9 and 13 in which the taper half-angle α was substantially the same and L1 / R1 was different. As a result, the number of punches that can be rolled was four for each punch. Therefore, for these punches, modified cutting was performed in the axial direction until the melted part disappeared, and the modified cutting amount of each punch was investigated. Specifically, the punch was changed and cut by 0.5 mm in the axial direction, and it was visually judged whether or not the melted part remained after the changed cutting. In the case of residual, and then modify the cutting 0.5mm in the axial direction. Table 3 shows the results of the investigation.

[0095] [table 3]

[0096] Test No.

L1 / R1

Change cutting amount...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

A plug includes a tip end, a tapered portion, and a barrel portion. The tip end has a spherical surface having a curvature radius R1 and length L1 which is smaller than R1. The tapered portion has a tip end external diameter D1, a back end external diameter D2 greater than D1, and a length is L2. The plug satisfies Expression (1), Expression (2) when 0 < L1 / R1 < 0.5, and expression (3) when 0.5 = L1 / R1 < 1. Since the tip end has a spherical surface with a curvature more gentle than a hemisphere surface, the diameter of the hole formed in the material at the tip end is greater than the hemispherical surface. According, the tapered portion is not brought into contact with the material. 0.5 D1 < L1 + L2 = 2.5 D1 (1) 1.0 < D2 / D1 = 1.4 (2) 1.0 < D2 / D1 < 1.8 -0.8 L1 / R1 (3).

Description

technical field [0001] The present invention relates to a punch, and more specifically, to a punch for a piercer used in a piercer for piercing a billet into a seamless pipe. Background technique [0002] The heated billet (round billet) is pierced by a punch used in a piercing machine to form a hollow billet tube. As shown in FIG. 11 , the punch 100 is disposed between a pair of inclined rolls 150 each inclined with respect to the pass line PL. After pressing the punch 100 into the billet 50 which is rotated in the circumferential direction by the inclined roll 150 , the piercer pierces and rolls the billet 50 along its central axis to form a hollow billet tube 51 . [0003] Since the punch 100 is in contact with the billet 50 during piercing and rolling, and receives heat and strong pressure from the billet 50, its surface is easily melted. As disclosed in Japanese Unexamined Patent Publication No. 9-29310, the melted punch is re-cut in the axial direction and reused. S...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): B21B25/00
CPCB21B25/00B21B19/04
Inventor 下田一宗山川富夫
Owner NIPPON STEEL CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap