Die Spray System Reduces Lubricant Consumption

July 1, 2005
A new system marries a waterproof robot to sophisticated dilution, mixing, pumping and spray techniques, along with a new die-spray nozzle.

The latest technique for applying lubricant to forging dies is Fanuc Robotics LR Mate 200iB/5WP waterproof robot, integrated with a dilution, mixing, pumping and spray system from Coating Management Technologies.

The robot is Fanuc’s latest addition to its popular LR Mate series of mini robots. The waterproof device operates at high-speed but is also flexible, so it can quickly access all areas of a die — even those that are typically hard to reach.

Fanuc Robotics’ LR Mate 200iB/5WP is the latest addition to the LR Mate series of mini robots. The waterproof robot provides high-speed operation coupled with flexibility, allowing it to access all areas of a die quickly, even those that are typically hard to reach.

The CMT system consists of a lubricant mixing/dilution station and a Pro-Hydro Module unit. It controls fluid flow, pressure, and die-lube consumption to maximize throughput and quality, and reduce operating costs. It is said to reduce lubricant consumption by up to a 70%, and simultaneously reduce air and water pollution. CMT’s new die-spray nozzle can vary its spray pattern from a small cone shape to a 360° flat-spray pattern, with no moving parts.

Advanced spraying
With the CMT Module unit lubricant is always diluted and prepared and sedimentation is prevented, so frictional conditions and part consistency are maintained from day to day. The nozzle-flushing system, automatic lubricant re-circulation, rotary filtering system, and nozzle filters prevent system problems or nozzle failures, reducing down time.

The positive-displacement pumps provide consistent and selectable application quantity for the lubricant for each die, regardless of changes in product viscosity or solids level.

Lubricant application quantity is controlled by changing the flow rate, not by adjusting spray time. This allows the operator to use the shortest possible spray time and still optimize application quantity, reducing press cycle time. Using water to cool the dies just before applying the lubricant (applied through the same nozzle as the lube), it reduces lube consumption and pollution to plant air and pit water by up to 70%.

By setting the cooling water “on” time to overlap with lube “on” time, the lubricant can be diluted accurately, “on the fly.” This allows the operator to use lower solids for less demanding parts, reducing the cost of lubrication and pollution even more.

The nozzle pre-pressurizing system provides instant spray fan shape, while the controlling system monitors all operations and sounds alarms in case of problems.

All system settings are stored and can be called later to be used with a specific part number. One Module unit can be designed to supply several presses and controlled with a central monitoring computer set up in a supervisor’s office, with total data logging. All Module unit functions are controlled electronically, so the system is ideal for integration with robotics.

Robot details
The LR Mate 200iB/5WP waterproof robot is called the industry’s first and only super protection robot designed for use in forging applications. The LR Mate 200iB/5WP has IP67 ratings. It will withstand reflected water flow at a distance of four inches, at a maximum pressure of 2,900 psi at four gallons per minute. The robot’s high-strength covers with Teflon gaskets resist chemicals or coolant fluids, and since it is not painted there is no risk of paint chipping during an application.

The LR Mate 200iB series has a slimmer arm than previous versions, enhancing its reach and minimizing interference. Though the arm size is smaller, the six-axis robot has enhanced payload capabilities. Brakes are available on all axes for better motion control. The wrist-moment capability is increased 33%, and maximum payload is increased 67% (from 3kg to 5kg).

The robot has a standard R-J3iB Mate mini controller to support various functions, including: single-phase power input; auxiliary axis support; line tracking; I/O and PC communications; Ethernet; Allen Bradley remote I/O; and Fanuc’s V-500iA vision sensor.

An enclosed controller cabinet means high reliability in a forge shop, and supports several features, including a built-in digital I/O port and a Fanuc I/O Link. The Fanuc I/O Link connector allows the R-J3iB Mate controller to be connected directly to any other Fanuc controller (robot, CNC, or IMM).

The robot uses a new acceleration/deceleration servo algorithm that reduces vibration and establishes what is called “the world’s fastest motion performance” in its class for the standard evaluation cycle (25-300-25 mm round-trip motion).

The R-J3iB Mate controller supports Collision Guard, Accuracy Enhancement Options, Multi-tasking, Ethernet interface, and over 40 other advanced software features that enable end-users to solve challenging manufacturing problems.

Mixing/dilution station
CMT's automatic mixing and dilution station consists of a mixing tank and holding tank with low-level, mid-level, and high-level sensors; control valves for water and air; mixers; and transfer pumps. One station can supply lubricant to multiple presses.

The mixing/dilution station includes a sonar system to measure lubricant and water levels, and pumps to transfer raw lubricant from the tote to the mixing tank, and then to the holding tank. The mixers in the tanks have adjustable timers to keep lubricant in suspension.

Through the interface, the operator enters starting solids and desired running solids. At the desired dilution ratio, the proper amount of lubricant is transferred into the mixing tank from the lubricant tote. Water is added, and the batch is mixed for a selected period before the transfer to the holding tank.

Lubricant application system details
The mixing/dilution station works with the CMT Pro-Hydro Module pumping unit, a positive-displacement system that controls application of lubricant onto a die surface. Positive-displacement means the pump can be installed any distance from the press.

Pumping action is provided by electrically driven positive-displacement pumps. Each has separate controls for die-cooling water application quantity, lubricant application quantity, nozzle-cleaning water application quantity, and atomizing air quantity. This allows for individual controls of each die position.

These are some of the parameters that can be set from the Module unit control panel: Lubricant dilution ratio, mixing time, re-circulation time, and interval; die cooling water/air delay/on time for each nozzle/die; lubricant flow rate for individual nozzles/dies; lubricant application on/off time for each nozzle/die; lubricant atomizing air on/off time for each nozzle/die; nozzle pre-pressurizing; maximum operating pressure for each nozzle; and nozzle flushing interval and time. When integrated with a robot, spraying parameters can be controlled by the robot throughout the spray cycle.

The positive-displacement pumps deliver +/-1% lubricant-flow accuracy, regardless of changes in viscosity, line back pressure, or atomizing air pressure. The lubricant flow rate per die position is 0.01 to 0.8 gallons/min. Application pressures up to 1,500 psi are possible, so the lubricant may contain up to 50% solids.

When the press is shut down., the CMT Module unit can automatically re-circulate the lubricant at selected times and intervals to prevent any potential sedimentation of lubricant and the need to flush the system. The nozzles can be automatically flushed with water after selected spray cycles or time intervals to prevent any lubricant from drying in the nozzles.

When the Module unit is connected to the air-assisted nozzles, the spray fan size can be automatically adjusted to match the die diameter/shape.

A data-logging system saves the following information for each part: Date and time, lubricant dilution ratio, nozzle pre-pressures, maximum nozzle pressure, die cooling water delay and spray times, lubricant flow rate per nozzle/die, lubricant delay and spray times, atomizing air delay and spray times, nozzle cleaning water delay and spray times, etc., as specified.