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:
Nov. 23, 1993
Filed:
Jun. 10, 1991
Applicant:
Inventors:
Kenneth Hicks, Wrekenton, GB;
Leslie Maine, Cramlington, GB;
Assignee:
British Gas plc, London, GB;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B29C / ;
U.S. Cl.
CPC ...
425392 ; 156155 ; 156196 ; 264320 ; 425383 ; 4254 / ;
Abstract
A die for reducing polyethylene pipe temporarily to enable it to be inserted in a pre-existing metal pipe is made of cast iron and has formations by which the die is splittable into two portions. The formations receive cylindrical bars which are squeezed together by a hydraulic squeeze off machine. Each formation is a U-shaped aperture with a saw cut extending from the base of the U into the ligament beneath the formation. The saw cut acts as a stress raiser. In a modification only one formation is provided. The die is made of grey cast iron or some other brittle material.