Valk Welding: 2004

Following the introduction of the universal folding robot last year, Valk Welding developed another interesting handling application for the metal industry: a robot for loading machining units. In the meantime, the first project at Heemskerk Fijnmechanica BV is ready for broader application in the machining sector.

In principle, a robot can imitate all human movement of the hands. That is: loading and unloading products, but also spray cleaning and unstacking by sort. A robot can also be provided with a camera and pick the products itself. The robot has to wait until the processing machine is finished? In that case, the robot can load a second machine.....

This is in short what Lucien Heemskerk, of Heemskerk Fijnmechanica BV in Waddinxveen, had in mind when searching possibilities to automate the machining units in his plant. For turning machines, Heemskerk has been using gantry-loaders for some time now to position the workpieces in the clamping chuck and to remove them. Lucien Heemskerk: "As regards machining units, most solutions are limited to automatic loading and unloading systems based on pallets, on which one workpiece can be clamped at the time. For smaller products you will be needing lots of pallets which makes the system quite expensive. That is why robot technology was a serious alternative for us, and we rightly ended up at Valk Welding. We have chosen for loading and unloading of the products on a conveyor, whereby the products are manually positioned. The robot takes piece after piece and after machining puts them back on the conveyor. According to us, this concept is the cheapest, most reliable and most versatile solution."

Over a year ago, Heemskerk Fijnmechanica BV together with Valk Welding linked a Nachi handling robot to a Victor machining unit. The robot is capable of handling 35 kg. The robot is provided with both vacuum cups and a gripper, in order to pick a broad range of products. The robot picks the products from the conveyor and puts them in a pneumatic clamping system on the table of the machining unit. After milling, the clamping system and product are being sprayed clean, then the robot picks up the product and puts it back on the conveyor, where it is discharged in a container. For large series, this process can be repeated unmanned for a long period of time. But Heemskerk also uses the cell for small series whenever convenient. Lucien Heemskerk: "Last night, the cell milled a series of 50 pieces completely unmanned. In principle, the cell is intended as a start for further automation of milling. In the initial phase, we want to be able to intercept surprises that might disturb the unmanned process,  such as breaking tools and contamination of clamps. In the meantime, these problems are under control and we intend to use the robot for a second machining unit."

Lucien Heemskerk sees a future for robots within the company, the more because robots can "serve" more than one machine. "We dispose of 17 turning machines and 20 machining units, the majority of which is being used for small series by one man and exclusively during the day. For larger series, we employ bar feeding and gantry-load systems. Some years ago, we invested in turning units with which we can completely machine products with one clamping. All in all, we have gathered a broad choice of production systems, and we are able to choose the best machine combination for each order."

Lucien Heemskerk knows about the prejudices of using robots, but these are brushed aside as doom-mongering: "The advantages exceed the disadvantages. Programming for example is not more complicated than for the average CNC-control. Of course, we are confronted with some unknown factors. That is why you have to start simple in order to master the process completely, and then you can speed up. Even in the optimisation phase, the process speed may not be regarded as the highest priority. The reliability, and in the end a constant and high quality, is of decisive importance for us."

(Source: various professional magazines - May 2004)