Automation for rubber and compounds
Batch after batch. The same compound.
Electrical and software for the mixing room and the lines downstream: weights within tolerance, repeatable cycles and, for every batch, the data to prove it.
In rubber
After the press, there’s no correcting it. What counts is what happens before.
A weight out of tolerance, a batch discharged too hot, a slab stacked before it has cooled: in rubber, the error starts upstream and shows up at the rheometer or, worse, on the finished part. That’s why the control system has two jobs: run the same cycle every time and leave a record of how it went.
The control system is our job, from the carbon black scale to the press: we design it, build it, program it and start it up. We work for the plant that has a sound machine and controls that need redoing, and for the machine builder designing a new one.
From weighing to press
Weight, temperature, speed, time. On every machine, one of them is in charge.
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The ingredients · Weighing
Out of tolerance, loading stops.
Carbon black and silica from the silos, oils injected into the chamber, polymers on the conveyor, chemicals in bags. The automatic scales feed at two speeds and correct for in-flight material on their own. The batch report keeps the actual weight of each ingredient, next to the recipe weight.
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The batch · Internal mixer
The cycle is a recipe in steps.
Rotor speed, ram pressure, ingredient additions, sweeps: every step has its values and its condition to advance. Discharge triggers on temperature, energy or time, depending on the compound. Chamber, rotors and drop door are temperature-controlled; the temperature and power curves of each batch stay on record.
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The slab · Discharge and batch-off
Speeds in cascade, a slab that doesn’t tear.
A twin-screw sheeter or an open mill makes the slab; then the anti-tack dip, the festoons, the stacker. Speeds run in cascade: the slab doesn’t tear, doesn’t pile up and stays in the festoons long enough to cool. The pallet is closed by weight, with its lot label.
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The profile · Extrusion line
Screw and conveyors tied together by weight per meter.
Weight per meter, read by the scale, corrects conveyor speed against screw speed. Barrel and head hold temperature by zone; above maximum head pressure, the screw stops. Shrinkage roller conveyor, cooling tank and cutter follow the line.
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The rubberized fabric · Calender
The same thickness, edge to edge.
The roll gap is adjusted from the thickness measured in-line; roll crossing or roll bending compensates for roll deflection, and each roll has its own temperature control. Tension is controlled by zone, from let-off to wind-up. The accumulator allows roll changes without stopping the calender.
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The cure · Presses and autoclaves
The cure recipe follows the mold.
Platen temperature, clamping pressure, degassing bumps and time change with the mold, or with the article in the autoclave. Cure time starts when the press is up to pressure. The cycle is recorded with its curves; a platen outside its band blocks the next load.
Have a machine that isn’t listed here? Write to an engineer.
Two names in rubber that have trusted us
What we bring to the line
All of the line’s controls. Or just the piece that’s missing.
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The electrical schematic
One sheet, for whoever wires it and whoever repairs it.
Main motor, temperature control, load cells, hopper and drop-door safety devices: a single set of schematics for the whole line, with terminal blocks and cable lists that use the same tags. Whoever wires it and whoever hunts for the fault read the same sheet.
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The panel
Built to live in carbon black.
Drives, safety devices and weighing instruments in a cabinet wired and labeled in our workshop. Where there is carbon black, a fine, conductive dust, the degree of protection and the cooling are decided at the design stage. The panel ships with its CEI EN 61439 declaration of conformity.
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The PLC and HMI software
The HMI says why it’s stopped.
Recipes with ingredients, tolerances and cycle steps, discharge criteria, batch report. The HMI shows which step the mixer is on and why it stopped: which scale, which door, which permissive is missing.
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Testing and start-up
Tested in the workshop, calibrated on the plant floor.
In our workshop, with the panel powered up, we test signals, sequences and safety functions. What’s left for the plant floor is scale calibration with test weights, the first real batches and time alongside the people who run the line on shift.
Questions
This is what the mixing room asks us.
Short answers. The rest we look at in front of the machine.
The mixer is fine, the controls are thirty years old. Can you redo just the controls?
Yes. The machine, the main motor and the field wiring stay. The PLC, the HMI and the drives left without spares are replaced; the cabinet, if it’s in good order, is upgraded, otherwise it’s rebuilt. We write the scope together, before the quote. Revamping: what stays, what changes
We have only one mixer. How long is the mixing room down?
It depends on how much work gets done beforehand: signal survey, panel tested in our workshop, program written around your recipes. What’s left for the shutdown is connections, tests and the first batches. The window is set around the production calendar; the old panel stays at the plant, ready to reconnect, for the agreed period.
The recipes are in the old system, some only on paper. Do they have to be rewritten from scratch?
They’re carried over to the new system compound by compound: from the old controller where they can be read, from paper where there’s nothing else. Before touching anything, we back up the program, parameters and recipes. Then we check each one together, on the first batch that uses it.
Our customer wants traceability for every batch. What data is kept?
Recipe, actual weight of every ingredient, cycle times, temperature, power and energy, discharge criterion, alarms. The data is tied to the lot and the pallet and can be passed to the plant systems, with a scope agreed with the people who manage them.
We run small lots, with dozens of recipes. Does it make sense to automate?
Yes. With the recipes in the system, a compound change is done from the HMI. Hand weighing of the chemicals can stay, guided: the HMI says what to weigh, the scale checks it, and the batch doesn’t start if an ingredient is missing.
Open-mill safety bar, hopper and drop-door interlocks: do you redo the safety systems?
Yes. We start from the risk assessment, then redo circuits and logic: bar or pull-cord stop with roll reversal or roll opening, interlocks, guards, reset. During testing, the safety functions are checked one at a time. Who is responsible for conformity is decided at the start, when the job is defined.
The line stops on an alarm nobody has ever seen. Who do we call?
Us: the person who wrote the program answers the phone. The first year of support is free. If the line has secure, authorized remote access, we connect from Mesero to read alarms and parameters.
To get started
Send us the machine as it is today. A photo, a recipe, a problem.
A photo of the machine and of the open panel, with the nameplate.
A typical recipe, even with the names blacked out: how many ingredients, how many steps.
Today’s problem: scrap, stoppages, spares you can’t find, missing data.
The form takes photos, PDFs and drawings. The reply comes from an engineer, within 1–2 business days.