“Connectedness isn’t just for electro mechanical drives any more,” says Jeroen Brands of GCC’s valued supplier, Rexroth, a Bosch Company, in a recent blog post on their site.
According to Brands’ post, the transition to connectable digital technology for hydraulic valves is accelerating, especially where European manufacturers are concerned. Seamless digital integrations are possible in connected equipment, a main outcome of which is an intelligent hydraulic valve for multiple automation functionalities where equipment is fully interconnected.
The technology is already showing new possibilities. There are smart single-axis controllers that are regulating hydraulic motions in closed loops. This is improved even further by a motion control that is built in to the on-board electronics of the valve, accurate within micrometers. Overall, the control quality relies almost solely on measurement system resolution. Additionally, smart technology is being deployed in variable speed pump drives, which opens up new possibilities, such as using for replacing throttle controls.
Sensors are another technology important to valves. Thanks to wide adoption in industries like automotive, sensors are cheaper than ever before. At long last, they’ve made their way in hydraulics and the possibilities are numerous: integration into valve housings, condition-monitoring such as for fluid quality and temperature, and remote device monitoring being just a few of the opportunities.
Further, mechanization for valves provides a greater degree of freedom regarding connection geometries. Currently, the industry is continuing to explore early ideas revolving around digital hydraulics, such as using control flows in a “stepped” way by employing single or multi-bit strategies. The appeal here is that it provides an advantage versus continuously variable technology.
These are not the only innovations regarding hydraulic valves worth noting, although connectivity is a common theme. Likely, connectivity will see an increased presence in the industry moving forward and if mechanisms and sensors are made uniform across the full spectrum of manufacturers, active connectivity and communications will be a reality. But even then, not every hydraulic valve will require digital electronics or be connected online. So an imprinted QR code that contains technical information about settings could be a good first step.
To this end, Rexroth has several innovations in the pipeline, including 3D printing of cores for cast housings, an efficient direct printing that considerably lowers energy consumption during valve operation. In the core’s design, the divisibility of the core mold is taken into account, thanks to core printing. The implication here is that other challenging designs are now usable that can lower pressure losses and improve energy efficiency, in some cases by up to 10 to 20 percent–a significant reduction.
For Rexroth, integrated axis controller valves can allow for motion control without a control cabinet, as it will be completely built into the valve electronics. Further it can be highly connective with open interfaces, even servo-hydraulic axes within its own fluid circuit. This allows for easy circuit assembly for axes, pulp, valves and cylinder, since the manufacturer only need to connect the power supply and control communication.
The same sort of tools for commissioning and user interfacing means that drive technology is homogenous in look and feel. There are several new plug-in amplifiers with pulse width modulation for on-off valves that can reduce the temperature of connections by up to 30 degrees in many instances, handy for applications like saw lines where inflammable dust is a concern.
In the next 10 years, Rexroth says that the industrial world will be a much better place because of valves, as we can expect to see easier project planning, more flexible commission, and more efficient operations.
