TFX calls for a 100% online control. Indeed, no one is immune to process drifts.
Thanks to control system, customer and supplier relationships can greatly be improved with objective figures.
General scheme of an industrial control application
Sample taken in the case of injection, can be all or partly transposed to most industrial needs.
The control of the process is carried out independently by the modules.
These can be loaded on the equipment, attached to the press or integrated into a mobile control.
The modules interact with their environment by reporting deficiencies: incomplete parts, risk of burns, risk of frailty in welding line, over or under-heating on the threshold or channels. The PC is only there to collect traceability data and to allow analysis. Everything is available for a continuous optimization and a strong commitment to quality.
Application notes :
Injection - Detection of short-shots
Aim: Automatic detection of short shots and injection defects.
Applications: Technical
parts or large series with high quality requirements.
Heat flux sensors are sensitive enough to detect without direct
contact heat transfer between the material and equipment during
injection. The amount of heat measured is directly related to process
parameters and quality of filling of the footprint.
Injection - Fluidity changes
Aim: Automatic Detection of batch to batch variations
Applications:
Optimisation of quality of technical parts.
Changes in viscosity of the material are
generally not sufficient to generate quality problems.However in some
cases where parts are very complex, where the process is pushed to
the extreme (high rates, temperatures), residual variations greatly
complicate the task of adjusters.Variations are much more pronounced when using
recycled material.
The injection is routinely accompanied by heat related to shear and friction.This heating is also directly related to the viscosity of the material.Control of temperature changes related to the matter in heavy loaded zones (channels or
threshold), provides access to these variations and help to optimize
settings.
Applications: Large series, smell sensitive applications
In thermosetting injection or compression, detection of heat released by curing reaction can be used for automatic "just in time" press opening.
This
approach reduces cycle time while ensuring reproducibility of cure level.Indeed, natural variability of these
processes (related to startups, thermal regulation, storage time and handling...)
limits cycle time reduction.To produce at optimum in given conditions, the cure time has to be adjusted for each part in order to avoid quality problems like uncontrolled bad smells.
RTM (Resin Transfer Moulding)
Aim: Non intrusive detection of resin flow front and cure monitoring (cure start and end).
Applications
: R&D, Vent control, Optimisation and Production traceability.
Heat flow
sensors measure the heat produced by curing reaction injected resin.This
measurement makes it possible to monitor in real
time
cure behaviour for each part produced and enable automation of curing cycle by end of cure detection.
Infusion of composites
Aim: Non intrusive resin flow front detection in stoves, cure monitoring.
Infusion of resins into reinforcements induces small thermal changes which are detectable with high sensitive of heat flux sensors.It is now possible to monitor resin flow front and resin cure even under caul plates or thick membranes.
Pultrusion
Aim: Process optimisation, cure monitoring
Applications: Large series, technical materials
The monitoring of thermal gradients in Pultrusion dies makes possible to detect and control exotherm peak position in real time. Such a system ensure optimum productivity of a line with a constistent cure level.
