Basic Principles of Hydraulics

The fundamental principles of hydraulics are straightforward:  

– Liquids do not have a fixed shape.  

– Liquids cannot be compressed.  

– Liquids enable a significant increase in work force.

Pascal’s Law  

The basis of modern Automotive Lift Repair Orlando hydraulics was established by Blaise Pascal, a French scientist, who formulated a key principle of hydraulics. Pascal’s law states that when pressure is applied to a confined liquid, it is transmitted uniformly in all directions and exerts equal force on equal areas, perpendicular to those areas. 

According to this principle, any force applied to a confined liquid is transmitted in all directions throughout the liquid, regardless of the shape of the container. This demonstrates how resistance on an output piston affects the pressure created in the fluid when the input piston is pushed downward, ensuring that the pressure is distributed evenly throughout the system.

When a solid bar is struck at one end, the primary force from the impact travels directly through the bar to the opposite end. This occurs because the bar is rigid, and the direction of the strike largely dictates the direction of the transmitted force. The greater the rigidity of the bar, the less force is lost within it or directed outward at right angles to the impact.

Similarly, when force is applied to one end of a column of confined Automotive Lift Repair Orlando liquid, it is transmitted straight through to the other end and equally in all directions—forward, backward, and sideways—causing the entire vessel to be filled with pressure. A good example of this is a fire hose; when filled with water under pressure, the flat hose assumes a circular cross-section, and the outward force of the water is uniform in every direction.

Multiplication of Forces  

Certain Automotive Lift Repair Orlando hydraulic systems are designed to amplify force. For instance, if piston 1 is smaller than piston 2, and the area of piston 1 is 2 square inches, applying a downward force of 20 pounds on piston 1 generates a pressure of 10 psi (20 ÷ 2) in the fluid. Although this force is smaller than the applied forces in other systems, the pressure remains the same because the force is concentrated on a relatively small area.

This pressure of 10 psi affects all parts of the fluid container, including the bottom of piston 2. Consequently, the upward force on piston 2, which has an area of 20 square inches, is 200 pounds (10 psi × 20). Thus, the original force has been increased tenfold while maintaining the same pressure in the fluid. In systems with these dimensions, the output force to input force ratio consistently remains 10 to 1, regardless of the applied force. For example, if the applied force on piston 1 is 50 pounds, the pressure in the system increases to 25 psi, which can support a resistant force of 500 pounds on piston 2.

If you depend on an Automotive Lift Repair Orlando hydraulic press for shaping metal components or performing other tasks in your facility, any malfunction can lead to productivity losses. Therefore, it’s essential to be aware of the most common hydraulic press issues and how to prevent them to ensure your business operates smoothly.

Continue reading to discover three prevalent hydraulic press problems, their causes, and proactive steps to avoid these issues before they arise.

1. Oil Leaks

Oil leaks are among the most frequent problems encountered with Automotive Lift Repair Orlando hydraulic presses. Not only do these leaks create messes and potentially cause malfunctions, but they also present significant fire hazards. Oil can leak from a hydraulic press in mist form due to high pressure and temperature, often going unnoticed until it ignites upon contact with an open flame, leading to rapid fires.

Leaks in a hydraulic press can occur from the piston oil seal, pump plunger, or release valve rod. 

Common causes of leaks from the piston oil seal include an overfilled oil reservoir, contaminated check balls, or damaged piston packing. To prevent these issues, avoid overfilling your oil reservoir, regularly clean or replace check balls, and replace piston packing before signs of wear and tear appear.

If oil is leaking from a pump plunger or release valve rod, the issue is usually due to loose packing nuts or worn packing. To prevent this, inspect the machine, tighten packing nuts as needed, and regularly replace packing.

2. Press Not Building Pressure

Another frequent hydraulic press issue is a press that fails to build pressure. Unlike oil leaks, the reasons behind a hydraulic press not producing pressure can vary widely. 

Before investigating other potential issues, check the system’s directional control setting to ensure it is not reversed. If everything appears correct, look for blockages that might prevent fluid from reaching the hydraulic pump, as a pump lacking sufficient fluid will not build pressure.

If fluid is reaching the pump, the lack of pressure may be due to problems with the machine’s drive motor. Damaged or misaligned drive motors can lead to pressure issues. 

While Automotive Lift Repair Orlando pump pressure problems can arise unexpectedly, you can mitigate them by properly maintaining your equipment and taking measures to avoid hydraulic fluid contamination, which can result in pump clogs.

3. Hydraulic Drift

Hydraulic drift is another common issue with hydraulic presses. It can lead to various problems, with the primary indicator being jerky movements during operation instead of smooth functioning. 

The main cause of hydraulic cylinder drift is unequal pressure across the piston in the cylinder, which can arise from several issues. 

Contaminated hydraulic fluid is one possible cause of hydraulic drift. Additionally, overheating of the hydraulic press system can damage seals, making them hard and brittle, impairing their function. Another potential cause of hydraulic drift is a leak in the piston rod seal; if severe, this leak can lead to complete failure of the piston rod.

To help prevent hydraulic drift, regularly inspect your system’s hydraulic cylinder. During these inspections, check the cylinder piston for corrosion that may indicate it needs replacement before drift occurs. Additionally, examine seals and connection devices for wear and tear, replacing any components as necessary.

Components of a Hydraulic System

An Automotive Lift Repair Orlando hydraulic system consists of various components designed to maintain fluid pressure, keep it clean, and ensure proper flow direction. Below is an overview of these components:

Reservoir Tank
It allows air bubbles to dissipate and contaminants to settle, while also enabling the oil to cool when it is not circulating.