Where the operator controls the feed rate in a cutting circuit, as found in trenching chains, drills, grade trimming wheels or saws, he will typically try to adjust the rate to prevent stall. A problem with this solution is that when the cutting is easy, productivity is lost. The simple circuit shown in Figure 1 may be a better solution in which stalling is eliminated and optimum feed speed maintained.
Figure 1. Incorporating a counterbalance valve in a cutting circuit can eliminate stalling and improve productivity
Operating principle
A counterbalance valve is a direct-acting, pilot-assisted relief valve. Pilot assist at port 3 lowers the effective setting of the relief valve at a rate determined by the pilot ratio. Port 3 of the counterbalance senses the pressure at the cutting device or saw. Port 1 connects to the feed circuit and port 2 goes to tank.
When the pressure required to drive the saw starts to climb too high, the effective setting of the counterbalance is lowered. Feed force will be modulated by relieving the feed circuit to tank, thus preventing the cutting device from stalling.
Design notes
This circuit is all about pressure control as opposed to flow control. Pressure control allows large changes in flow with small changes in pressure. The determining factor in this circuit is the pressure at the cutting device. Do not get too caught up in numbers. There are at least three performance curves involved and trying to predict exactly what will happen is difficult, if not impossible.
In order to serve this purpose, the counterbalance valve has to have enough capacity to handle the flow of the feed circuit. The counterbalance valve will probably need a low pilot ratio and a high setting.
The seven different types of hydraulic fittings used for cylinders
Hydraulic systems & components
Hydraulic fittings are crucial for maintaining the integrity of hydraulic circuits, Selecting the right type of hydraulic fitting is not only essential for preventing leaks but also for ensuring minimal downtime and enhancing overall system efficiency.
Read more...Control without complexity Axiom Hydraulics
Electrical switching & drive systems & components
In an era where precision, performance and smart control define industrial success, the right driver can make all the difference. At Axiom Hydraulics, we’ve seen firsthand how the Sun Hydraulics XMD series transforms hydraulic systems, from mining and construction to agriculture and automation.
Read more...The seven different types of hydraulic fittings used for cylinders
Hydraulic systems & components
Hydraulic fittings are crucial for maintaining the integrity of hydraulic circuits, Selecting the right type of hydraulic fitting is not only essential for preventing leaks but also for ensuring minimal downtime and enhancing overall system efficiency.
Read more...Powering southern Africa’s industrial evolution for over five decades
Editor's Choice Hydraulic systems & components
Established in 1974, Oilpower is a recognised name in South Africa’s hydraulic and pneumatic sector. What started as a small, family-run business has matured into a highly structured operation with specialised teams, experienced engineers and a reputation for technical excellence and reliability. Oilpower is celebrating its 50th anniversary this year.
Read more...Choosing the right hydraulic cylinder for your application CT Hydraulics (Nqoba)
Hydraulic systems & components
Selecting the appropriate hydraulic cylinder for your specific application involves considering several key factors to ensure optimal performance, efficiency and durability. Here’s a comprehensive guide to help you make an informed decision.
Read more...Hydroformed tube valve body for diaphragm valves
Hydraulic systems & components
One of the most common necessities for manufacturing pharmaceuticals, cosmetics, food and beverages are diaphragm valves. What used to be a dull two-way race between forged and cast body variants is now being challenged by an exciting, ground-breaking technology. The hydroformed, light-weight diaphragm tube valve body will change the way you think about plant design and operation.
Read more...Problem solving under pressure Axiom Hydraulics
Editor's Choice
The greatest strength of Axiom Hydraulics lies in the company’s ability to solve complex problems and adapt systems to meet unique challenges. This capability stems from two key factors: the diverse experience of its team members, which spans decades across multiple disciplines, and their unwavering dedication to their clients.
Read more...Proportional cartridge valve series is the fastest in its class
Hydraulic systems & components
Parker Hannifin is introducing the enhanced version of the proportional cartridge throttle valve series, TFP. The new pilot valve further reduces the step response times by up to 30%, making the TFP the fastest valve in its class.
Read more...The six pillars of hydraulic system health Hydrasales
Hydraulic systems & components
Hydrasales, a leader in hydraulic and lube oil industry solutions, offers an extensive range of condition monitoring products designed to safeguard your systems. Here are six essential checks for hydraulic system health to keep your systems in optimal shape.
printer friendly version