we do know that very often the question is put why just Michenfelder is so far the only manufacturer who succeeded to master this challenging task.
We are pleased to explain why this location of the sand testing system is exactly the right one and that the measurement there is not belated at all and why controlling the compactability with Michenfelder does work so extraordinarily well and that consistent results directly at the moulding machine can be guaranteed.
The key to success is interlinking and control-technical coupling of the sand testing system at the moulding machine with the continuous moisture control system with super-fine resolution at the green sand mixer. As moisture and compactability correlate, this system is in the control concept, as a finely reacting adjusting device, of dominant importance.
The moisture measuring and control system already ensures, because of the correlating behaviour of moisture and compactability, pre-stabilisation of compactability.
When now the sand composition changes the system registers the smallest deviations from the set compactability value and adjusts by feedback to the moisture measuring and control system in the mixer permanently and in finest steps the required water amount to the slowly changing sand composition maintaining automatically the compactability at the moulding machine on a constant level.
Beyond that, the various changes occurring in the sand when conveyed from the mixer to the moulding machine, due to follow-up saturation of the bentonite, evaporation and temperature effects, varying dwell times, sand aerators and conveying belt transfer points can, till today, only be registered fully automatically and reliably offset by this particular arrangement and interlinking of the modules of the Moulding Sand Management System FoMaSys.
By means of this system arrangement it is possible to warrant across all production phases an extremely narrow fluctuation range of compactability of s = ± 2% directly at the moulding machine. With reliably and sufficiently pre-moisturised used sand this system arrangement produced during daily routine consistently a standard deviation which, with s = ± 0.8 – 1.5%, is still much better. No other system can achieve this. For the capability of a modern foundry to operate with regard to sand with permanently low scrap rates, it is thus of critical importance at which point in the process of reconditioning the moulding sand possesses consistently the best mechanical properties. This point is not the mixer, but the moulding machine.
There is a choice of two different on-line sand testing systems. The proven VEDIMAT, with which the compactability and the green compression strength are determined and the brand-new ONLINE-SANDLAB (currently still in the internal pilot period).
With this new ONLINE-SANDLAB Michenfelder (r)evolutionises the monitoring and control of moulding material parameters and complements the modular Moulding Sand Management System FoMaSys. In a compact automatic testing unit for conveyor belt installation there are several devices combined for the determination of a so far unequalled multitude of quality-relevant variables for sand preparation. For the first time, also permeability testing has been relocated away from the laboratory into the sand preparation process. This relocation allows action and reaction based on an enormously enlarged and directly at the moulding plant generated database in real time.
(VEDIMAT = V / SANDLAB = S)
With stand-alone operation:
In combination with process control system MiPro:
When connected to moisture measuring and control system in the mixer: