As a concept, right-sizing is inherently linked to smart machine design, which brings about rewards such as optimised space, considerable savings on components and installation, inherent safety by design and, oh yes, that all-important future-proofing against ever-changing requirements.
Of course, the design engineers need a sound understanding of standard machine components, as well as knowledge of current machinery safety standards and a firm grasp of the desired outcome in terms of machine function. Meeting all of these requirements when selecting products is a process known as right-sizing. In pneumatic applications right-sizing can impart considerable benefits, especially with regard to valve manifolds.
Valves are generally sized by cylinder bore, actuation speed and required pressure. In the past, the entire valve manifold would be sized based on the largest force/speed requirements to ensure enough flow was present in the pneumatic system, or by splitting between two manifolds (low and high pressure/flow). However, this methodology results in waste, both in terms of compressed air and the expense and size of the manifold, not to mention the labour needed to install two manifolds.
Today, right sizing is achieved by selecting the correct valve for each actuator on one manifold based on speed and bore size for a given flow requirement. In addition, we are pleased to report that some ISO valve manifolds, such as Parker’s H Series, offer a broad range of flows (0.55 Cv up to 3.0 Cv) on one manifold for ease of right-sizing.
Here’s a practical application to consider. Assume a machine that needs the following: four actuators requiring <0.5 Cv; four actuators requiring 1 Cv; and two actuators requiring 2 Cv. This application can be sized several different ways based on the highest flow requirements (solution 1), by splitting the application into two different manifolds for varying flow (solution 2), and by right-sizing each valve to the corresponding actuator (solution 3).
In this example, a cost estimation was produced for a collective hard-wired system and a networked (Ethernet) system in all three solutions. Right-sizing each valve to the corresponding actuator (solution 3), proved to be the most cost effective for both. Beginning with hard wiring, right-sizing saved $92 against solution 2, and $656.60 against solution 1. Similarly, for the networked system, right-sizing produced savings of $552 compared with solution 2 and $656.60 when pitched against solution 1. In addition, labour is not included in these estimations, which would be a particular cost for solution 2, where two manifolds have to be installed.
We can say with certainty that right-sizing works for a number of reasons. Aside from certain valve manifolds offering a broad range of flows, buying just one manifold means purchasing fewer overall components. In addition, the cost of smaller valves is less, installation costs are reduced and less space is consumed within the machine.
Think smarter, lighter and faster.
If you would like to find out more about Parker’s H Series valve manifolds, and the benefits they can bring to machine-building projects, read the white paper "Why Right-Sizing Matters".
Article contributed by Linda Caron, product manager for Factory Automation, Pneumatic Division
24 May 2019
Manufacturing businesses have witnessed the rapid ascension of industrial networks, and in the pneumatics industry, there’s a real desire to ensure the benefits that connectivity can bring are leveraged. To maximise this opportunity, those looking to connect pneumatic valve manifolds to an industrial network will want to make sure of an optimised outcome. But how?
To begin with, select the network and communications protocol that is best suited to the application.
Common Ethernet networks and protocols, such as PROFINET IO, EtherNet/IP, EtherCat and Modbus TCP, have been around for some time now. However, the high cost of adopting such systems has restricted the range of their application to those requiring the highest levels of system sophistication. This factor is precisely why cost-effective fieldbus networks like PROFIBUS DP, DeviceNet, CANopen and AS interface have become popular for more straightforward operations.
And yet these too, are getting squeezed out of the picture. To find out why we only need to look at rapidly emerging technologies like wireless networks and open communications protocols. A clear case in point can be seen with IO-Link, which thanks to simple installation, better control and enhanced diagnostics capabilities, has already secured a large user base.
In support of IO-Link’s increasing stature, Parker has released its P2H network node, an addition to the H Series ISO valve platform. The good news is that P2H delivers a robust way of connecting H Series valves to the IO-Link network, therefore saving total system and installation costs compared with Ethernet or hard wiring.
Applications include vehicle body welding and assembly, along with systems for applying adhesives and sealants, end of arm tooling (EOAT) for robots, riveting machines, blow moulding machines and case erectors, to list but a few.
Regarding network connectivity, flexibility and modularity are the factors underpinning ease-of-use and space saving. The value of our P2M IO-Link node module, for example, is as a low-cost network connection with simple integration and easy-to-use local diagnostics. In addition, voltage monitoring and cycle counting are available through the network, simplifying diagnostics and supporting the take-up of predictive maintenance strategies.
Many general pneumatic control applications can benefit from such modules, including packaging machines, automotive systems and factory automation. In fact, if you happen to visit any automotive or packaging facility, the ‘elephant in the room’ will be clear to see: the big controller cabinet housing the PLCs and contactors. These cabinets consume valuable floor space, but now they are set to shrink in size. Safety relays are increasingly moving out of the cabinet, and trends indicate that PLCs are soon to follow. This ‘do more with less’ business model should encourage any of you who typically still hard-wire valve manifolds, to make that leap towards industrial networks.
24 Apr 2019
This blog post will describe current best practice or optimising the installation of a continuous position sensor (CPS) on to a pneumatic linear actuator.
For the purposes of the guidance, we’ll use the Parker P8S CPS (Continous Position Sensor) as a reference example. Despite being available in a range of configurations – including IO-Link or analog feedback signal, a choice of outputs and various measuring ranges – the installation procedure is common for all P8S types.
The P8S CPS is suitable for direct mounting to any T-slot cylinder. So, as a point of note, if another cylinder variant is used, such as a tie-rods or round body type, separate brackets will be required.
First of all, please appreciate that the CPS should be installed in line with the correct operating voltage. After all, there will clearly be differences between, say, an M8 analog connection versus an M12 IO-Link.
When ready to begin, move the position of the cylinder’s piston to the desired starting point – known as the zero point. Now you can insert the CPS into the cylinder’s slot or bracket, with the cable pointing back towards the zero point. To determine exactly where the CPS should be positioned, move the device until the yellow LED is illuminated. Then, slide the CPS away from the zero point until the LED turns off, and slide it back again to the position where it lights up once more. That’s your position for the CPS, so you can now secure it in place using the set screws.
Moving to configuration, this process can be performed using the teach button on the CPS. With the CPS correctly installed and the piston in the zero position, press and hold the teach button for two seconds. The LED should now blink and you can release it. The zero point has been stored in memory.
Next, set the piston position for the end point of the desired measurement range. Press the teach button once, and the measurement range has been stored. The analog signal or IO-Link process data is now configured to this range.
So far, so good. Now, move the piston from zero point to end point and check to ensure the LED remains lit throughout the travel. If you notice that the LED turns off at any point, simply repeat the configuration steps above.
To reset the measurement range to the maximum possible range, press and hold the teach button for five seconds. If you are deploying the IO-Link version of the Parker P8S, the measuring range can be configured using parameter commands, which also outline how the teach button can be locked out, for example. You can refer to the installation guides for more details on specific parameter commands.
All pretty straightforward - like anything it’s only easy if you know what you’re doing! Hopefully this short blog has proved useful in highlighting best practice when it comes to installing and configuring CPS sensors.
Watch in this video How to Install and Configure the P8S Continuing Position Sensor.
Article contributed by Franck Roussilon, product manager, Actuators Europe, Parker Hannifin, Pneumatic Division Europe
11 Apr 2019
25 Mar 2019
To ensure optimum machine safety, design engineers need a solid understanding of the Machinery Directive 2006/42/EC and how to comply with required safety levels.
A safety exhaust valve when incorporated into an air preparation system, lets the user safely and reliably shut off the pneumatic energy, stopping compressed air-flow to the machine and allowing downstream pressure to exhaust.
Installing a pneumatic safety exhaust valve is a simple and cost-effective way to achieve machine safety and to comply with the directive.
Here are four things to consider for your application:
To eliminate the danger of residual energy making its way into the machine, select a solution which offers a series-parallel flow design, such as Parker’s P33 valve. This permits higher exhaust flow capability and ensures low residual pressure during a fault.
Essentially, the two valve elements are arranged such that air from inlet to outlet must pass through both valves in series, but the flow path from outlet to exhaust is in parallel.
Cross-flow technology ensures that both valve elements (redundant design) must shift to supply air downstream and, if either valve element is out of position with the other, downstream air will dump to exhaust in parallel.
Monitoring detects faults or failures in control systems, and checks for short-circuit faults. The monitoring portion of a safety system must check if both sides of the safety valve shift together every time by monitoring the condition of pressure-operated sensors. These sensors are hardwired into the controls and monitored by the external control system.
This is generally done with most safety relays and safety PLCs. The use of sophisticated controls and monitoring ensures sensors are not bypassed and faults are detected so the valve functions as intended.
Statistical component life (B10d) is key to any safety component. When designing a safety system according to ISO 13849-1, each component in the system needs a B10d or a mean time to dangerous failure (MTTFd).
Engineers use a B10d value, along with the number of operations (nop) to determine the MTTFd of the component for the application:
MTTFd = B10d/nop.
Valves that use electromechanical components for monitoring are usually limited by the life of the circuit boards or mechanical wear parts.
Using solid-state electronic pressure sensors for monitoring greatly improves the B10d numbers as there are no mechanical wear components.
The required Performance Level (PLr) should be determined by a risk assessment. Once a PLr is determined, application statistical component life (MTTFd), controls architecture (Category), diagnostic coverage (DC), and consideration of common-cause failures (CCF) can be used to determine the system PL. The system PL must equal or exceed the Performance Level.
For applications where the severity of injury and level of exposure to the hazard are high, the percentage of diagnostic coverage of the monitoring system must be high as well. Depending on the safety relays or safety PLCs used, the system can achieve a High-Performance Level, up to PL e and Safe Integrity Level to SIL 3.
If a risk assessment demands a safety rating of PLc or higher, a redundant safety exhaust valve is a simple-to-implement and cost-effective way to attain the required safety level.
Our white paper Selecting & Integrating Pneumatic Safety Exhaust Valves provides more in-depth support with the correct specification and integration of safety exhaust valves.
Article contributed by Linda Caron, global product manager for Factory Automation, Pneumatic Division.
12 Mar 2019
With the ever-increasing complexity of modern pneumatic components, it becomes crucial to know what to look for and what is best suited to your system. Choosing and maintaining system components wisely, right through from compressors to workstations, can help save the expense of unplanned downtime or costly rebuilds. Conversely, a few wrong choices can lead to everything from wasted energy to system failures. To avoid these pitfalls, here are some simple steps to take when looking to maximise the performance of your company’s all-important pneumatic components.
Preventive and predictive maintenance
Just like carrying out maintenance tests and oil changes on a vehicle, pneumatic systems also require regular upkeep to prevent more serious issues down the line. In compressed air systems, it is important to ensure that lubricators are not left to run dry; filters are cleaned; and all contaminants such as rust, metal shavings, water, and unwanted oils are removed.
Predictive maintenance is about being proactive, rather than reactive, to avoid component failures, and it is often the work of sensors (available for almost every factory component) that alert you to potential problems. A flow sensor that fits in-line with a Filter Regulator Lubricator (FRL) unit are able to identify blocked filters, while continuous position sensors can be an indicator over time to the wear to which cylinders are exposed.
Compliance and safety
Making sure that a system is compliant with current standards is also critical to avoid costly downtime and equipment overhaul. The recently-updated standard known as DIN ISO 8573-1 governs filtration levels. Defined down to the micrometre, it identifies the solids, water and oil that should be separated out to maintain a well-functioning system.
Similar to checking system compliance, carrying out a risk assessment and consulting an administrative body that serves those involved in workplace health and safety are important procedures to help minimize the risk of workplace injuries. Bringing in light curtains, interlocks, machine guarding or safety exhaust products to block or prevent hazards can be impactful measures in this regard.
Specification and integration
Right from the start of the specification process, selection of accurately sized equipment saves money and valuable energy, which oversizing wastes. As alternatives to oversizing and waste, consider implementing pressure boosters that allow the flow from a compressor to the largest workpiece, and pneumatic zoning on manifolds that can be used to mix pressures. The simple step of locking regulators prevents workers from adjusting a system’s overall pressure to supply more air to individual workstations which ultimately could damage a sealing system, waste energy, or even cause physical harm.
Updates in terms of the connectivity of the factory floor are worth considering as well. Low-cost Ethernet connections are more frequently replacing hardwired solutions and associated trunks of cables to provide network-based connectivity across a facility. IO-Link connectivity, to run field-level devices back to the IO-Link master, provides further opportunity for savings in time, wiring, component cost and troubleshooting. Additionally, many of today’s advanced network nodes are able to supply prognostic data for predictive maintenance and in-built sensors to check for shorts, over current, cycle counting, thermal management, among other things.
If you would like to discover out more about Parker’s range of pneumatic components, please click here.
Article contributed by Linda Caron, global product manager for Factory Automation, Pneumatic Division.
5 Mar 2019