Drawing machine for drawing tubes

Patent metadata

Field	Value
Publication number	US-11097325-B2
Application number	US-201916294675-A
Country	US
Kind code	B2
Filing date	Mar 6, 2019
Priority date	Nov 20, 2013
Publication date	Aug 24, 2021
Grant date	Aug 24, 2021

Abstract

A drawing machine (1) for drawing a tube (2), defining a longitudinal axis (Y), comprising a first die (3) for carrying out the drawing of the tube by means of the use of a mandrel (4); a device for varying the inclination (5) of the tube inlet into said first die (3); a second die (6) for carrying out a skin pass operation on the tube, arranged downstream of said first die (3); an in-line system for detecting the eccentricity of the tube; a data processing system (7) for processing signals originating from said detection system and sending input data to said device for varying the inclination (5) of the tube to vary the inclination of the tube so as to correct the eccentricity of the tube in-line; wherein said in-line system for detecting the eccentricity of the tube comprises a first detection head comprising at least three first transducers (8) arranged downstream of said first die (3).

First claim

The invention claimed is:

1. An in-line method for correcting an eccentricity of a tube during a drawing thereof, by means of a drawing machine, the method comprising the following stages:
drawing the tube by means of a first die;
carrying out a skin pass operation on the tube by means of a second die;
carrying out a first in-line detection of the eccentricity of the tube by means of a first detection head;
wherein said first in-line detection is provided at said second die and/or at an area arranged downstream of said first die and upstream of said second die;
processing the signals originating from said first detection head by means of the data processing system and sending input data to an inclination variation device so as to vary the inclination of the tube with respect to the longitudinal axis and to correct the eccentricity of the tube in-line.

2. A method according to claim 1 , wherein there is provided a second in-line detection of the eccentricity of tube by means of a second detection head arranged downstream of said second die; and there are provided stages of processing the signals originating from said second detection head by means of the data processing system and sending further input data to the inclination variation device.

3. A method according to claim 1 , wherein there is provided a second in-line detection of the eccentricity of tube by means of a second detection head arranged downstream of said second die; and there are provided stages of processing the signals originating from said second detection head by means of the data processing system and sending further input data to the inclination variation device.

Assignees

• Danieli Off Mecc

Inventors

• Angelilli Andrea
• Crespan Luca

Classifications

• B21C51/00 Primary

  Measuring, gauging, indicating, counting, or marking devices specially adapted for use in the production or manipulation of material in accordance with subclasses B21B - B21F · CPC title

• B21C1/24

  by means of mandrels · CPC title

• B21C3/14

  Die holders combined with devices for guiding the drawing material or combined with devices for cooling, heating, or lubricating · CPC title