The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 07, 1987
Filed:
Jan. 21, 1986
Dennis H Sansome, Sutton Coldfield, GB;
Gerald M Jones, Bewdley, GB;
National Research Development Corporation, London, GB;
Abstract
A plug for use in the plug drawing of hollow tubes or other stock. A flexible and deformable seal is mounted on the rearward part of the plug. In its relaxed state this seal allows easy insertion of the plug into the stock before drawing begins. In its deformed state, which it is caused to adopt in use, it effectively seals the rearward end of a cylindrical clearance between the plug and the stock, so enabling this clearance to be filled with pressurized lubricant to improve drawing efficiency. The lubricant is supplied through passages formed in the plug and connected to a hollow conduit extending backwards within the undrawn stock. The conduit may be flexible, or may be rigid and then act as a plug bar. The plug may be in two parts which are caused, as drawing begins, to move relative to each other and in so doing to deform the seal.