Ramsey Oretronic IV Tramp Metal Detector REC 4479C
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Introduction
This section
introduces the Thermo Scientific™ Ramsey™ Oretronic IV Tramp Metal Detector
(TMD IV). It gives
an overview of the device’s capabilities,
provides information on installing, operating and maintaining the
device, along with technical specifications and reference drawings.
Overview
The TMD IV detects the presence of tramp metal in bulk material being transported on a conveyor belt.
Detected tramp metal can then be removed from the process stream manually or automatically by mechanical
means. Removing the tramp metal protects crushers, material handlers, and process equipment from the
damage it may cause.
This highly reliable system detects all types of tramp metal that could be found in bulk material on belt
conveyors even when it is buried in wet, conductive materials. Tramp metal could include such things as
bucket teeth, manganese steel mantles, bore crowns, bar scrap, chains, and tools. The bulk material (or
burden) can be product such as iron pellets, minerals, aggregates, coal, or coke.
The TMD IV can be installed on conveyors with speeds up to 1,800 ft/min (9 m/s). In addition, because it is
insensitive to materials with high magnetic permeability and electrical conductivity, this detector can be used
in applications where conventional metal detectors produce an unacceptable false alarm rate.
The TMD IV control unit includes software that helps ease system setup and calibration. The operator interface
provides easy-to-read indicators, and a membrane-switch keypad.
Theory of Operation
The TMD IV operates by generating a pulsed magnetic field (the primary magnetic field) that is radiated from
its transmitter coil. This field generates an output signal in the receiver coil (see Figure 1-1).
Figure 1-1. Magnetic Fields Generated by the TMD IV
When the pulse is turned off, eddy currents induced in tramp metal produce a secondary magnetic field. This
new field also generates an output signal in the receiver coil. The detector measures the effect of this
secondary magnetic field only during the time the primary field is inoperative.
