Type	PMGG 123-S	PMGG 123-F
Min. thickness
for low alloyed copper and aluminum	0.010 mm (foil mode)	0.010 mm (foil mode)
	0.025 mm (normal mode)	0.025 mm (normal mode)
for high resistivity material (450 nΩm)	0.040 mm (foil mode)	0.040 mm (foil mode)
	0.100 (normal mode)	0.100 (normal mode)
Max. thickness	15 mm	6 mm
Repeatability	±0.03% (not better than 0.3 μm)	±0.03% (not better than 0.3 μm)
Accuracy	±0.05 % (not better than 0.5 μm)	±0.05 % (not better than 0.5 μm)
Total Accuracy Standard mode (relative permeability=1.0)	Non-ferrous metals	Non-ferrous metals
strip thickness > 2.0 mm	±(0.05% + 2 μm)	±(0.05% + 2 μm)
strip thickness < 2.0 mm	±(0.1% + 1 μm)	±(0.1% + 1 μm)
Min. strip width	250 mm	140 mm
Strip position
for changes faster than 1 mm/s	±5 mm	±3 mm
for changes slower than 1 mm/s	±10 mm	±8 mm
Strip slope	±3°	±3°
Step response	15 ms	15 ms
Operation temperature	+5 - +55°C	+5 - +55°C
Degree of protection	IP 65	IP 65
Power supply (from the control unit)	24 V DC, max. 3 A	24 V DC, max. 3 A
Dimensions (W x D x H)
Gauge without holder	198 x 425 x 302 mm	160 x 425 x 293 mm
Weight
Gauge	50 kg	37 kg
Gauge holder	30 kg	30 kg

The heavy-duty design of the gauge and the stability of the measuring principle makes the Millmate Thickness Gauging System superior in applications that previously were considered impossible. Measurement can be done close to the rollgap, without removal of emulsion.

Material
The MTG is designed for dependable gauge measurement on a wide range of non-ferrous materials with different alloy compositions and resistivities, i.e. aluminium, copper, zinc, tin, lead and beryllium.

Single or Double gauge system
In reversing mills it is very common to use thickness gauges on both sides of the mill. The MTG system offers two different control units, one for handling a single gauge and the other for handling two gauges. The user-friendly operator unit has a display function for double gauge configuration. The operator can see the thickness gauge deviation graphs, one for each gauge, on the same menu page.
The feature with double gauge systems can also be valuable in applications like tandem mills or slitting lines.

Sledge
As an option ABB offers a sledge design with a number of stroke lengths. It is the difference between strip width (min./max.) used in the mill that mainly decides how the sledge should be designed for each specific application. The sledge motion range should be designed so that the gauge can be fully withdrawn from the strip.

The Millmate Thickness Gauging system is based on the Pulsed Eddy Current technology, which uses magnetic fields for measurement of the strip thickness. The interaction between an applied magnetic field and the electrically conductive strip indicates the thickness - without influence from material composition or conditions in the measuring gap.

Phase 1: Transmitting

• An electric field is generated with a transmitting coil
• The field is applied until it fully penetrates the strip
• The field "energy" is stored in the air gap and in the strip
• The amount of energy stored in the strip depends on the thickness alone - not on resistivity

Phase 2: Distance measurement

• Fast air response just after transmit field is swithed off
• The measurement of air gap energy corresponds to distance between coil and strip
• Pulse time t1 is typically less than 5μs

Phase 3: Resistivity measurement

• Response from the surface area of the strip
• The measurement starts when the air gap signal has declined
• The measurement of the surface response corresponds to resistivity and is dependent on the speed of the field leakage out of the strip

Phase 4: Thickness measurement

• Response from the whole strip
• The measurement starts when the air gap signal has declined (phase 3 is included in phase 4)
• The measurement of the whole strip corresponds to the complete energy stored in the strip, and continues until the strip response has almost declined (t3)
• The measurement corresponds to the strip thickness
• The resistivity does not affect the level of the whole strip response
• The tail part after t3 is calculated with the use of the resistivity part

Type
Single gauge system	PMGA 121
Double gauge system	PMGA 122
Supply voltage	115/230 V +10/-15%
Power consumption	300 VA
Thickness output	±10 V
Digital inputs	24 V nominal, opto insulation
Digital outputs	24 V/0.5 A, opto insulation
Operation temperature	+5 to +45°C
Dimension W x D x H
Elkapsling wall cabinet	800 x 300 x 800 mm
Elkapsling floor cabinet	800 x 400 x 1900 mm
MNS Select floor cabinet	840 x 656 x 2225 mm
Weight
Elkapsling wall cabinet	75 kg
Elkapsling floor cabinet	250 kg
MNS Select floor cabinet	250 kg
Protection class
Elkapsling wall/floor cabinet	IP 54
MNS Select floor cabinet	IP 21/IP 54

 

The Millmate Thickness Gauge System can easily be connected to AGC systems, based on feedback, feedforward and mass flow control.

Network communication
OPC (www.opcfoundation.org) can be used as an alternative to I/O-signals for integration. The system supports OPC 6.1 Data Access over an optional Ethernet local network. To gain access to measurement data and system set-up, a computer with OPC-client functionality can communicate with the Control unit via an optional OPC-server.

Profibus-DP
As an option, the MTG system can be equipped with a Profibus-DP slave interface for communicating with e.g. the rolling mill control system. The Profibus-DP interface provides fast transfer of measurement data. It can also be used for setting up nominal thickness and for remote control of system settings and gauge movement.

Single or Double gauge system
In reversing mills it is very common to use thickness gauges on both sides of the mill. The MTG system offers two different contol units, one for handling a single gauge and the other for handling two gauges. The user-friendly operator unit has a display function for double gauge configuration. The operator can see the thickness gauge deviation graphs, one for each gauge, on the same menu page.
The feature with double gauge systems can also be valuable in applications like tandem mills or slitting lines.

Type	Hydraulics
Working pressure	50 bar
Input pressure	max 160 bar
Flow	5 l/min
Pressure switch	40 bar
Pressure fluid	Mineral oil DIN 51524 (HL, HLP) Phosphate ester (HFD-R)
Sealing	Viton

 

Air regulator
Supply pressure	5 to 16 bar (72,5 to 232 psi)
Air consumption	5 dm3/s (11 cfm)
Air quality requirement	Acc to PNEUROP
Particle class 3	Particle size max 1 μm (40 μin), particle content max 5 mg/m3
Oil content class 3	Max1 mg/m3
Condensation class 3	Condensation at +10° C (50 °F)

 

Data	Standard Gauge	Foil Gauge
Accuracy for strip thickness < 2 mm*	±(2.0 µm + 0.1 %)	±(2.0 µm + 0.1 %)
Accuracy for strip thickness > 2 mm*	±(3.0 µm + 0.05 %)	±(3.0 µm + 0.05 %)
Thickness range	0.035 - 15 mm	0.025 - 6 mm

*Provided information about clad layer parameters is correct

 

Data
Accuracy (at 20 °C)	±1.2 % < 0.1 mm (of resistivity reading for thickness)
	±1.0 % < 0.1 mm (of resistivity reading for thickness)
Measuring range	16 - 450 nΩm (4 % - 110 % IACS)
Output data	Resistivity in nΩm
	Conductivity in MS/m or % IACS
Input data	Strip temperature
	Analog input from external source
	Serial com. data from external source