Patents Assigned to Marshall Richards Barcro Limited
  • Patent number: 4644769
    Abstract: A multi-stage steel wire drawing machine has, in each stage, two dies and a single drive motor for drawing the wire through the two dies. In a preferred arrangement the dies are mounted side-by-side and an idler wheel used to define part of the wire path between the dies in the stage and a coaxial driven wheel is used to draw the wire through both dies in the stage and to define part of the wire path leading to the next stage. Dry wire lubrication before die entry and water cooling after passage through the dies are disclosed.
    Type: Grant
    Filed: July 14, 1986
    Date of Patent: February 24, 1987
    Assignee: Marshall Richards Barcro Limited
    Inventors: John W. Pamplin, Brian R. Astbury
  • Patent number: 4464922
    Abstract: A method and wire drawing apparatus are disclosed in which rapid cooling of the wire is effected by directly contacting the wire with liquid as it leaves the die and ensuring the wire passes through a bath of coolant while on the block. The bath can be formed against the wire-engaging surface of the block by a cowl.
    Type: Grant
    Filed: May 13, 1982
    Date of Patent: August 14, 1984
    Assignee: Marshall Richards Barcro Limited
    Inventors: John W. Pamplin, Brian R. Astbury, Richard Shillito
  • Patent number: 4345451
    Abstract: Method and apparatus for drawing wire which uses a partial turn of wire wedged in an endless groove in a rotating wheel to generate the necessary drafting tension and wherein the drawn wire is cooled by direct contact with a liquid coolant as it leaves the die and while it is wedged in the groove. In a multi-stage apparatus, the coolant is removed from the wire downstream of the wheel and upstream of the next sizing opening by an air wipe.
    Type: Grant
    Filed: December 10, 1979
    Date of Patent: August 24, 1982
    Assignee: Marshall Richards Barcro Limited
    Inventors: John W. Pamplin, Brian R. Astbury, Richard Shillito
  • Patent number: 4120186
    Abstract: This invention relates to a method of determining the sequence of die sizes to be used in a multi-die/block drawing machine to draw metal from any given input stock size to any given final wire size to give optimum efficiency and proposes nomograms for achieving the sequence quickly and easily.
    Type: Grant
    Filed: June 1, 1977
    Date of Patent: October 17, 1978
    Assignee: Marshall Richards Barcro Limited
    Inventors: John Warner Pamplin, James Vine Bennett, Peter Fred Elson
  • Patent number: 4096726
    Abstract: The invention relates to an improved method and apparatus for tube drawing which relates to the use of a floating plug and die arrangement, the necessary draughting tension in the tube being drawn being generated by a rotatable tube block around which the tubing downstream of the die is wrapped. The invention proposes to mount a tube guide upstream of the die in such wise that the relative spacing between the guide and the die can be a minimum during threading-up of the die but increased during drawing.
    Type: Grant
    Filed: February 11, 1977
    Date of Patent: June 27, 1978
    Assignee: Marshall Richards Barcro Limited
    Inventors: Otto Uhlmann, Norbert Stephan
  • Patent number: 4092875
    Abstract: The invention is concerned with a method of and apparatus for the continuous drawing of metal tubing by the die and floating plug method using rotating drawing blocks to provide draughting tension. Tube lengths are processed joined end-to-end in sequential stages with accumulators provided between adjacent dies to permit the receipt of tubing from the upstream die and the supply of tubing to the downstream die to be at different rates. Each joint between lengths is broken upstream of a die but remade downstream thereof, the accumulator absorbing and supplying tube from/to adjacent blocks while the tube rejoining process is effected.
    Type: Grant
    Filed: February 11, 1977
    Date of Patent: June 6, 1978
    Assignee: Marshall Richards Barcro Limited
    Inventors: Otto Uhlmann, Norbert Stephan