Rexline’s Remaining Cover Thickness (RCT) Monitor is an on-line device and can measure the remaining cover thickness of either the carry or pulley covers of Steel Cord belting, running under normal operating conditions.
The device comes in two forms:
RCT BASIC
This model is designed to be permanently fixed to a conveyor structure, with the underside of the Sensor Head 30.0 mm above the surface of the steel cords After installation and calibration, it produces a continuous 4 – 20mA signal output proportional to remaining cover thickness.. This signal is easily integrated into a site SCADA system. In new belting with say 15.0 mm carry cover, this places the Sensor Head15.0 mm above the surface of the belt.
Collision reduction is built into the mount, which allows the Sensor Head to swing away from the belt, should contact be made. However, if a working distance of +/- 15.0 mm from the belt surface is unacceptable, a second model is available.
RCT ALPHA
The RCT Alpha has a “Safe Parking” feature, which allows the Sensor Head to be retracted to a parked position 160 mm from the belt surface, when not required to make measurements.
Cover wear rate in belting is relatively slow, even in short-cycle belts. This means that measurements need only be taken in weekly or monthly. Even then, usually two belt cycles provide sufficient data for trending purposes. This means that the RCT Alpha can be parked for most of its life cycle.
RCT Alpha is a very sophisticated device and is designed to communicate with the site over a Network connection and TCP. All data is logged on board in non-volatile memory, where it is available for download and analysis. A Tacho and belt Lateral Position Indicator (LPI) are included, which provide longitudinal and lateral belt position data, which is also logged.
The “Safe Parking” function can be either manual or automatic. In automatic mode, the device can be programmed to make its measurements at a nominated time and date, say the third day of every month at 10pm, for example. Firmware uses the LPI and a user-defined lateral ‘window’ to deal with the issue of belt wander.
After a defined interval, usually two belt revolutions, the device automatically parks and waits for data download instructions. The RCT Alpha comes with Proprietary software, which runs on the Network under Windows 98- WIN7. This allows device configuration and calibration as well as data download / viewing , including export of data to any destination as .CSV files.
There are two 4 – 20mA outputs, re-transmitting remaining cover thickness and belt lateral position. As with the RCT Basic, there is in-built Collision Reduction.
GENERAL
Both devices mount off a transverse steel tube, attached to the conveyor structure. This allows them to be positioned anywhere across the belt width. The sensing location is typically over the Tail Pulley.
The target area or ‘footprint’ being sensed is +/- 100 mm square. This means in a running belt, a ‘strip’ of belting +/- 100 mm wide is being measured. This being the case , it is essential to have the device located over the area of maximum wear across the belt. This location is determined from historical (or current) static belt cover profile measurements.
In the RCT Alpha, the LPI senses belt wander so that it is possible to limit data capture to the desired strip of belting.
Either device can be AC or DC powered.
The on-belt hardware is rated IP67 and IP68.
The electrical enclosure is 304 stainless steel, rated at IP69K (NEMA 4x).
All cabling is run in Anaconda Type EF Grey flexible steel conduit, rated at IP67, including fittings.
