METHOD OF AND APPARATUS FOR MAKING PIPE FROM A TUBULAR WORKPIECE

• US 20100199740A1
• Filed: 02/01/2010
• Published: 08/12/2010
• Est. Priority Date: 02/11/2009
• Status: Active Grant

• Current Assignee: SMS MEER GmbH (Bernhard-Weiss-Stiftung)
• Original Assignee: SMS MEER GmbH (Bernhard-Weiss-Stiftung)
• Inventors: Steingiesser, Klaus, Muschalik, Uwe
• Granted Patent: US 8,459,085 B2
• Time in Patent Office: Days
• US Class Current: 72/370.25
• CPC Class Codes: B21J 13/08 Accessories for handling work or tools
• CPC Class Codes: B21J 13/10 Manipulators in general B25J

Abstract

A tubular workpiece with a throughgoing bore is held by a handler having a passage alignable with the bore and of a predetermined inside passage diameter. A rod carrying a mandrel and of an outside rod diameter is provided with a guide having an outside guide diameter slightly smaller than the inside passage diameter but greater than the outside rod diameter The passage is aligned by the handler with the workpiece bore and the mandrel is inserted through the handler passage into the workpiece bore while sliding the guide along the passage and centering the rod in the passage with the guide out of contact with an inner surface of the passage. The workpiece is externally engage around the mandrel with forging tools and thereby forged around the mandrel.

Claims

1. A method of making pipe from a tubular workpiece having a throughgoing bore, the method comprising the steps of:

holding the tubular workpiece in a handler having a passage alignable with the bore and of a predetermined inside passage diameter;

providing a rod carrying a mandrel and of an outside rod diameter with a guide having an outside guide diameter slightly smaller than the inside passage diameter but greater than the outside rod diameter;

aligning the passage by means of the handler with the workpiece bore and inserting the mandrel through the handler passage into the workpiece bore while sliding the guide along the passage and centering the rod in the passage by means of the guide out of contact with an inner surface of the passage; and

externally engaging the workpiece around the mandrel with forging tools and thereby forging the workpiece around the mandrel.

2. The pipe-making method defined in claim 1, further comprising the step while forging the workpiece of:

holding the guide in the passage.

3. The pipe-making method defined in claim 1, further comprising the step of

providing a lubricant on the inner surface of the passage or an outer surface of the guide before inserting the guide into the passage.

4. An apparatus for making pipe from a tubular workpiece having a throughgoing bore, the apparatus comprising:

a handler for holding the tubular workpiece and having a passage alignable with the bore and of a predetermined inside passage diameter;

a rod carrying a mandrel and of an outside rod diameter;

a guide on the rod and having an outside guide diameter equal to or slightly smaller than the inside passage diameter but greater than the outside rod diameter;

means for, when the passage is aligned by the handler with the workpiece bore, inserting the mandrel through the handler passage into the workpiece bore while sliding the guide along the passage and centering the rod in the passage by means of the guide; and

a forger for externally engaging the workpiece around the mandrel with forging tools and thereby forging the workpiece around the mandrel.

5. The pipe-making apparatus defined in claim 4 wherein the guide is formed of an inner part on the rod and an outer part defining the outside rod diameter and shiftable about a point on the inner part.

6. The pipe-making apparatus defined in claim 4 wherein the inner part has a part-spherical outer surface centered on the point and the outer part fits around the inner part and has a complementary and concentric part-spherical inner surface.

7. The pipe-making apparatus defined in claim 5 wherein the outer part has a substantially cylindrical outer surface complementary to the inner surface of the passage and is formed at an end turned toward the forger with a chamfer.

8. The pipe-making apparatus defined in claim 5 wherein the rod is provided with clamps axially fixing the inner part on the rod.

9. The pipe-making apparatus defined in claim 4 wherein the passage inner surface is cylindrical and the guide has a complementary cylindrical outer surface.

10. The pipe-making apparatus defined in claim 4, further comprising:

means for rotating the mandrel and rod about an axis of the rod.