초록 ▼

A method of manufacturing a marker post includes the steps of preheating a tubular barrel adjacent to a lower end thereof to soften same and deforming the tubular barrel lower end to form a flange assembly. The pre-softened tubular barrel is received in a barrel holder. A mandrel assembly is recipro

A method of manufacturing a marker post includes the steps of preheating a tubular barrel adjacent to a lower end thereof to soften same and deforming the tubular barrel lower end to form a flange assembly. The pre-softened tubular barrel is received in a barrel holder. A mandrel assembly is reciprocated into and out of engagement with the barrel lower end. The mandrel assembly reshapes the barrel lower end to form the flange assembly.

대표청구항 ▼

1. A method of making marking posts comprising tubular thermoplastic barrels with upper ends and flanged lower ends, which method comprises the steps of: providing a barrel with first and second ends and a bore extending between and open at said ends;applying heat to said barrel lower end and thereb

1. A method of making marking posts comprising tubular thermoplastic barrels with upper ends and flanged lower ends, which method comprises the steps of: providing a barrel with first and second ends and a bore extending between and open at said ends;applying heat to said barrel lower end and thereby presoftening same;restraining said barrel along the length thereof against axial movement;providing a mandrel with a base, a mandrel plug mounted on and projecting generally perpendicularly from said base and an annular transition between said base and said plug;providing said transition with a concave, curved configuration;providing a linear actuator with extended and retracted positions;mounting said mandrel on said linear actuator in alignment with said barrel bore;placing said linear actuator in said retracted position;advancing said linear actuator axially to its extended position;telescopically advancing said mandrel plug into said barrel bore;engaging said barrel first end with said mandrel transition;deforming said barrel first end in a first, radial outward direction by advancing said mandrel into said barrel bore and thereby forming a barrel end extension portion;further deforming sand barrel first end in a direction generally axial with respect to said barrel and radially towards same; andmaintaining an upwardly-open channel formed by a spacing between said flange rim and said barrel.2. The method according to claim 1, which includes the additional steps of:forming said barrel from a thermoplastic material; andheating said thermoplastic material to a predetermined temperature at which said material becomes sufficiently soft for reshaping same.3. The method according to claim 1, which includes the additional steps of:placing said marker post at a buried electrical power line location;extending a conduit from said buried electrical power line into said bore;extending electrical power leads through said conduit and into said bore; andterminating said power lead with insulators within said bore.