Holding Valves Are The Answer

When a crane’s hydraulic cylinder is required to hold its position for an extended period, holding valves are how they do it. There are many holding valves on a boom – two per cylinder in fact – one on the piston side and one on the rod side. You can locate them by looking for a rectangular steel block housing a cartridge on a hydraulic cylinder. Let’s take the outrigger as an example. The first thing you will need to do as an operator is set up on level and firm ground. Next, you lay your pads onto the ground firm and level. Lastly, place your outriggers as wide as permitted and engage the hydraulics to lift onto the ground and stabilize your boom. The holding valve is working to protect the safety of you and your machine in the event of a hose failure. It does this by clicking closed after you correctly position your outriggers. The holding valve is released each time you power up or down. It takes approximately 300 PSI to release them. Load holding valves provide increased safety and performance in many hydraulic system applications, like lifting. Signs that a holding valve is weak or failing is drifting of a load. In our example of an outrigger, the machine will soften up on one side and tilt. Worse yet, if not repaired,  overturn on the truck and boom can occur. Luckily holding valves failing is rare on well designed hydraulic circuits. To check your holding valves, raise your boom with a load on it. Shut the truck (PTO) off. Using the control valve, try to lower the load. You might hear a clicking sound, but for sure the load will not lower. This is just one of the many things we check during a Lifting Device Safety Inspection. So, call us for your boom inspections. We know about proper holding valve performance. At Crane Tech we save you money. Using Crane Tech keeps your workers safe. If you are in Crown Hill, Dalston, Craighurst, Hillsdale or Horseshoe Valley give us a call. We inspect cranes, auto hoists, elevating lift platforms, bridge cranes, racking to name but a few. Remember that the Crane Tech Inspection team can conveniently inspect all your lifting equipment at the same time. One call for all your lifting equipment! Crane Tech inspects and maintains your Hoist Lifting Equipment. Call us at 705-734-0012. See us on Instagram. On the web www.craneservices.ca. We know your equipment best.