Which hydraulic components are used in an excavator?
An excavator contains several hydraulic systems. Cylinders move the boom, arm and bucket. A slewing ring with a hydraulic motor lets the upper structure rotate.
In the centre of the machine, a hydraulic rotary joint transfers oil from the undercarriage to the rotating upper structure, often combined with electrical slip rings for signals and power. Hydraulic travel motors drive the tracks.
Hose burst valves on the boom cylinders protect against hose failure, and hydraulic ball valves are used to switch between functions when an attachment is changed.
- Which hydraulic components are used in an excavator?
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An excavator contains several hydraulic systems. Cylinders move the boom, arm and bucket. A slewing ring with a hydraulic motor lets the upper structure rotate.
In the centre of the machine, a hydraulic rotary joint transfers oil from the undercarriage to the rotating upper structure, often combined with electrical slip rings for signals and power. Hydraulic travel motors drive the tracks.
Hose burst valves on the boom cylinders protect against hose failure, and hydraulic ball valves are used to switch between functions when an attachment is changed.
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- What does a hose burst valve do on an excavator?
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A hose burst valve protects people and the machine if a hose or pipe fails while the boom is under load. The valve detects the sudden increase in flow and blocks it, so the boom does not drop.
Depending on the design, the load stops completely or lowers at a controlled, limited speed, giving anyone underneath time to move away. Because the oil is held in the cylinder, it also does not end up on the ground. Hose burst valves are especially important when an excavator is used to lift loads.
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- What is a hydraulic rotary joint on an excavator?
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A hydraulic rotary joint, also called a swivel joint, lets the upper structure of the excavator rotate continuously while oil keeps flowing between the undercarriage and the upper structure. It has several separate channels, for example for the travel motors and the return line.
Often, it is combined with electrical slip rings that transfer power and signals in the same rotating connection. Because the joint has to fit the specific design of the machine, it is often a custom component.
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- Do larger excavators need more hydraulic components?
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Not necessarily more, but larger components. The hydraulic functions of a compact excavator and a large excavator are largely the same: digging, slewing and driving.
As the machine and its loads grow, the cylinders, valves, motors and pumps scale up accordingly. Selecting the right size for the load and duty cycle is therefore essential.
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- How does a hydraulic excavator drive?
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Each track is driven by a hydraulic travel motor at the base of the machine. The pump sends oil to these motors, which turn the tracks.
In hybrid and electric excavators, the way the pump is driven changes, but hydraulic functions often remain. We help OEMs work out how hydraulics fits into these new concepts.
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- Is custom hydraulics possible for excavators?
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Yes. Many hydraulic components in an excavator are standard, such as hose burst valves. Where the machine design sets specific requirements, custom work is often needed. This applies in particular to the rotary joint and electrical slip rings in the centre of the machine: the number of channels, the connections and the installation dimensions are determined by the machine itself.
Custom solutions can also be needed for switching between attachments, or when an excavator is developed as a hybrid or electric concept. We start from what your machine has to do, determine whether an existing component will do, and work out an adaptation where it does not. We then test it with you and stay involved until it runs in series production.
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