摘要:
A mill with travelling stand, wherein to eliminate sliding of the passes on a tube being rolled, there is a mechanism for moving the racks during mill operation, the mechanism being designed so as to ensure variations in the rolling radius when the tube is strained.
摘要:
A ROLLING MILL PLUG FOR USE IN A SEAMLESS ROLLING PLUG MILL TO REDUCE AND ELONGATE THE PIERCED SHELL BEING FORMED INTO SEAMLESS PIPE AND CONSISTING OF A CYLINDRICAL BODY HAVING A PLURALITY OF SECTIONS OF DIFFERENT DIAMETERS SOME OF WHICH SECTIONS ARE OF UNIFORM DIAMETER AND SOME OF WHICH ARE FRUSTA-CONICAL.
摘要:
A rolling mill comprising a bearing block supporting the rolls and adapted to be subjected to reciprocating movement, said bearing block being integrally connected to a mobile mechanism comprising two eccentric masses, turning in opposite direction in synchronism with the reciprocatory displacements of the bearing block.
摘要:
THE OPERATION OF DRIVERS FOR THE ROLLS OF A ROW OF ROLLS STANDS IN A ROLLING MILL FOR TREATMENT OF HOLLOW BLOOMS WHICH ARE MOUNTED ON MANDRELS AND ARE CONVERTED INTO TUBULAR ARTICLES DURING A PASS THROUGH THE MILL IS REGULATED IN SUCH A WAY THAT THE SPEED OF THOSE ROLLS WHICH ENGAGE THE BLOOM IS REDUCED WHEN THE LEADING END OF THE BLOOM REACHES THE ROLLS OF THE SECOND STAND AND, WHERE APPROPRIATE, AGAIN WHEN THE LEADING END OF THE BLOOM REACHES THE ROLLS OF ONE OR MORE NEXT-FOLLOWING STANDS, AND WHEN THE TRAILING END OF THE BLOOM LEAVES THE ROLLS OF THE FIRST STAND AND, WHERE APPROPRIATE, AGAIN WHEN THE TRAILING END OF THE BLOOM LEAVES THE ROLLS OF ONE OR MORE NEXT-FOLLOWING STANDS. THE REDUCTION IN THE SPEED ROLLS IS A FRACTION OF THE DIFFERENCE BETWEEN THE SPEED OF THE MANDREL PRIOR AND SUBSEQUENT TO ENTRY OF THE LEADING END OF THE BLOOM INTO A PARTICULAR STAND OR A FRACTION OF THE DIFFERENCE BETWEEN THE SPEED OF THE MANDREL PRIOR AND SUBSEQUENT TO ISSUE OF THE TRAILING END OF THE BLOOM OUT OF A PARTICULAR STAND.
摘要:
A device to process a blank (3) that includes at least one outer shaping tool (8) that may be radially positioned or radially displaced. An inner shaping tool (9) is mounted co-axially to the main machine axis (x) of the main spindle (1.1). The inner shaping tool (9) may be axially displaced and/or axially positioned with respect to the axial position of the outer shaping tools (8).
摘要:
The plug is for expanding the inside diameter of the end portion of a metal pipe. Its cross section is a circle, and includes a taper portion and a parallel portion connected to the tail end of the taper portion. The diameter of the taper portion gradually increases from the head end of the taper portion to the tail end of the taper portion where the diameter is D1. The axial distance LR from the point where the diameter D2=D1×0.99 to the tail end where the diameter is D1 satisfies the Expression 22≦LR/((D1−D2)/2)≦115. The taper angle on the surface where the diameter is D2 is larger than or equal to the taper angle on the tail surface of the taper portion following the point where the diameter is D2. The diameter of the parallel portion is D1.
摘要:
An exemplary embodiment of the invention provides a method for producing an ultra thin wall metallic tube by cold working method with significant wall thickness reduction. In a method for producing the metallic tube with a cold pilger mill according to the invention, cold rolling is performed while tube diameters are being expanded using rolls having tapered groove dies whose calibers increase from an engaging entry side toward a finishing exit side. In a method for producing the metallic tube with a drawing machine according to the invention, cold drawing is performed while the tube diameters are being expanded using a solid die whose calibers increase from an engaging entry side toward a finishing exit side and a plug of a tapered mandrel bar whose diameters increase from an entry side of the die toward an exit side. In the metallic tube producing method, a maximum diameter of the plug or tapered mandrel bar may be larger than an outside diameter of the mother tube.
摘要:
An apparatus for sizing a pipe end comprising: a plug 3 for sizing the pipe end; a chuck 2 for clamping the pipe; and shifting means for shifting the position of the plug 3 and/the chuck 2, which are placed successively from the end of the pipe 2, and the plug 3 has a circular cross section, and is constituted by a taper portion 31 and a diameter equivalent portion 32 continuously formed from the tip of the plug in succession. The outer diameter of the taper portion 31 is gradually expanding from the tip toward the rear end while satisfying the following formulas (1) and (2). The chuck 2 is capable of changing clamping position of the pipe 1. This apparatus makes it possible to size the inner diameter of a pipe end with superior dimensional precision 22≦LR/(D1×0.01/2)≦115 (1) R2≧R1 (2).
摘要:
An exemplary embodiment of the invention provides a method for producing an ultra thin wall metallic tube by cold working method with significant wall thickness reduction. In a method for producing the metallic tube with a cold pilger mill according to the invention, cold rolling is performed while tube diameters are being expanded using rolls having tapered groove dies whose calibers increase from an engaging entry side toward a finishing exit side. In a method for producing the metallic tube with a drawing machine according to the invention, cold drawing is performed while the tube diameters are being expanded using a solid die whose calibers increase from an engaging entry side toward a finishing exit side and a plug of a tapered mandrel bar whose diameters increase from an entry side of the die toward an exit side. In the metallic tube producing method, a maximum diameter of the plug or tapered mandrel bar may be larger than an outside diameter of the mother tube.
摘要:
By employing a Cr-plated mandrel bar for producing hot seamless tubes according to the present invention wherein centerline average roughness Ra in axial and circumferential directions as well as maximum depth Rv in axial and circumferential directions is specified and further maximum height Rp in axial and circumferential is specified, surface defects such as seizure unlikely generate in an elongation-rolling process by a mandrel mill so that the service life can be dramatically extended, thereby the remarkable reduction of tool cost can be achieved. Moreover, it contributes greatly to improve the inner surface quality of hot seamless tubes to be rolled by a mandrel mill rolling process. Also, the manufacturing method by the present invention makes it possible to efficiently manufacture Cr-plated mandrel bar for producing hot seamless tubes.