Why Replace a Valve System with a Manifold?
As the number of valves in a pneumatic system grows, flow paths can begin to look like a plate of spaghetti. Aesthetics aside, these sprawling flow paths often increase the overall size of the valve system, lengthen response times and lead to leaks. For these reasons, it can be beneficial to replace space-hogging valve systems with manifolds, which reduce the number of external connections, decrease system complexity and consume less space in industrial applications.
Valve System vs. Manifold
Conventional pneumatic valve systems move fluid (in the form of compressed air) from a bulk source through hoses and tubing and distribute it to a system of line-mounted valves and actuators. While manifolds, which may still use hoses and tubing to carry compressed air from the bulk source, provide a centralized location where multiple valves within a system are connected and are located where there is available space within the machine or equipment.
Manifolds are often employed in process-focused operations, such as oil and gas, chemical and food and beverage processing facilities. In these applications, they often connect multiple valves together in a pneumatic system and play a role similar to that of an air-traffic controller: Manifolds may open some valves, close others and leave some valves partially opened or closed as needed for the process.
Manifolds may also be found in the pneumatic systems of compact instruments, robots and medical equipment, as well as a range of pneumatic systems where they direct compressed air through the circuits of the system.
What are the Advantages of Replacing a Valve System with a Manifold?
Placing most of the valves in a pneumatic system within a single manifold that is mounted where space is available on a machine or within the system provides several advantages, including reduced space requirements, faster actuator response times, fewer leak points and simplified installation and maintenance.
Reduced space requirements
Manifolds are more compact than valve systems because they remove and/or centralize hoses and tubing while consolidating multiple valve functions into a single unit that is attached to an area within the machine where space is available. Manifolds may be configured to control more valves within the existing footprint or the same number of valves within a smaller area, helping to reduce space requirements within machinery, devices or a process plant.
Because the flow paths are shortened and straightened within a manifold, actuator response times may be reduced. Also, because manifolds operate multiple valves, they encourage more efficiency and, potentially, more throughput from the same line. In addition, shorter fluid paths than those found in conventional valve systems may decrease pressure drops. Combined, these advantages can lead to improved productivity and energy efficiency.
Fewer leak points
Reducing the number of hoses and connections results in fewer opportunities for leaks within the pneumatic system.
Simplified installation and maintenance
Typically, manifolds can be mounted directly to a machine or DIN rail and many units can be installed vertically or horizontally, which is much less time consuming and difficult than installing the multiple valves and connections found in a conventional valve system. In addition, maintenance is simplified when using a manifold because valves can be replaced as units. Decreased requirements for tubes, hoses and fittings are also likely to reduce spare parts inventories, along with the related costs.
When Does Using a Manifold Instead of a Valve System Make Sense?
Because manifolds significantly reduce the size of the valve system, they are the obvious choice in applications where the pneumatic system footprint is a major concern, such as within a medical device or a mobile system, and where available floor space is at a premium, such as in industrial processing facilities. Manifolds are also the better option when valves or their fittings were previously inaccessible for maintenance. Other good candidates for the use of manifolds include situations in which actuator response time is crucial.
What Types of Manifolds are Available?
There are two main manifold types and selection will depend upon the system type, size and purpose. Single-piece manifolds include fixed-length (also known as drilled-block) manifolds, which can be custom designed. They are composed of a block of metal, into which the passages for the air flows are drilled. Drilled-block manifolds cannot be easily modified and only allow users to mount valves where the holes are drilled in the block, which is usually pre-determined during the manufacturing process.
Modular manifolds consist of metal blocks that can be bench assembled horizontally and stacked as needed for an application, permitting users to design a manifold that meets their needs. They can also be ordered ready to install. Modular manifolds allow users to gain the benefits of manifolding while avoiding a lot of the design time and costs associated with customized single-piece manifolds. They can also be modified to meet changing needs.
To determine whether replacing a valve system with a manifold is right for your pneumatic application, please contact a JHFoster engineer.