Hydraulic System Failure Analysis of a Plate Rolling Machine

The hydraulic system is the most important part of a Plate Rolling Machine. 

And even a small hydraulic failure can make your entire production line stand still!

There are several reasons why hydraulic systems fail. 

It can be caused by a sudden pressure drop, a mysterious leak, or overheated oil, and these problems can appear without warning. 

And, by the time you take any action to control it, you have already started losing some valuable time and money. Plus, it affects your delivery schedule.

So, if you’ve ever faced a hydraulic failure or are worried that one could affect your operations, you’ve come to the right place!

In this blog, we’ll discuss the most common causes of hydraulic system failures in plate rolling machines. 

We’ll also understand the consequences in case of a hydraulic failure and how to prevent them. 

Hydraulic System Failure Analysis of a Plate Rolling Machine: Table of Contents

• What Is the Role of the Hydraulic System in a Plate Rolling Machine?

• What Are the Common Causes of Hydraulic System Failures in Plate Rolling Machines?

• How to Troubleshoot Root Causes of Hydraulic Failures?

• 5 Preventive Measures and Maintenance Strategies

• Your Hydraulic System Deserves Expert Care

• Hydraulic System Failure Analysis of a Plate Rolling Machine: FAQs

What Is the Role of the Hydraulic System in a Plate Rolling Machine?

If you have watched a plate rolling machine smoothly bend thick metal sheets, you have already seen the power of a hydraulic system at work. Yes, the real power of this machine lies in its hydraulic system.

Here is a simple explanation that will help you understand how all the machine's components function and how the plate rolling machine works.

• Hydraulic Pumps: Hydraulic pumps generate pressure in the fluid and propel it through the system.

• Cylinders: Think of cylinders as muscles. They convert fluid pressure into mechanical movement to drive the rollers.

• Valves control the flow of fluid and regulate the amount needed. They ensure the right amount of force is applied to the correct spot.

• Filters: Contaminated oil can lead to major failures. So these filters are placed to keep the hydraulic oil clean. 

• Motors: These power the movement of the rollers and other connected parts.
  

What are the functions that the hydraulic system controls?

Now, let’s talk about the actual functions that are controlled by the hydraulic system:

• Roll Movement: Up, down, in, out—every roll movement is powered by hydraulics.

• Pressure Application: The hydraulic system applies the right pressure. It automatically adjusts according to the thickness and toughness of the metal.

• Clamping and Positioning: The hydraulics provide a steady grip on the metal plate, ensuring every bend is clean and precise.

If they aren't maintained properly, any of the parts may fail. A failure will bring your entire production line to a standstill. To help you avoid such situations, we are going to discuss the exact causes of a hydraulic failure so you won’t have to remain clueless and take the necessary actions.

What Are the Common Causes of Hydraulic System Failures in Plate Rolling Machines?

Your plate rolling machine might be durable, but at the end of the day, it is a machine. So, there is always a chance that it can develop some problems.

1. Hydraulic Fluid Leaks

Hydraulic fluid leakage is a common problem in plate rolling machines. A damaged oil seal, worn-out hoses, or loose fittings can cause it.

Consequences Of Hydraulic Fluid Leaks

When the hydraulic fluid starts to leak, you’ll observe subtle changes in how the machine is working:

• The system can’t build the required pressure

• The rollers don’t move the way they should

Apart from performance loss, spilled fluid can cause you or any employee to slip on the floor, becoming a safety risk for your employees.

2. Contaminated Hydraulic Oil

These machines operate under tough conditions, including dirty floors, high temperatures, and continuous work. Hence, it’s no surprise that the oil can pick up dirt or debris.

The problem starts when this dirt or debris causes wear and tear to the internal parts, and the lubrication doesn’t happen properly. 

Consequences Of Contaminated Hydraulic Oil

After the internal parts are damaged due to contaminated hydraulic oil, you will notice sluggish movement and unusual noises during operation.

3. Pump and Motor Failures

Your pump rolling machine is in continuous use, meaning the Hydraulic pumps and motors run similarly and work under continuous pressure.

If the pressure exceeds the pump’s rating, the pump will fail. Other reasons, such as trapped air in the pump line or fluid cavitation, may also be present. 

Consequences Of Pump And Motor Failures

You’ll get to know about a pump or motor failure when: 

• The roller speeds become inconsistent

• The machine starts making loud vibrations

• The machine's performance drops significantly

Pump and motor failures are a serious red flag, and you should immediately address them. 

4. Overheating of Hydraulic Fluid

Heating is normal in a machine, but overheating is a serious issue. 

When the hydraulic oil becomes too hot, its viscosity decreases, and it loses the ability to lubricate and pressurize the system properly. It eventually leads to increased internal component wear. 

Consequences Of Hydraulic Fluid Overheating

As soon as such a situation occurs, you might start to notice: 

• A burning smell

• Low system responsiveness

• Warped seals

If overheating causes a fire or leakage, it can lead to a serious accident. Therefore, we recommend regularly checking the fluid temperature. 

5. Pressure Drop Issues

There may be situations where you experience a sudden and unexpected pressure loss. One of the most common reasons for this can be: 

• Internal leakages in the pump or directional valve

• The valves may have failed

• Severe blockage in the system. 

If there is a sudden drop in pressure during operations, it can damage the metal sheet. 

Troubleshooting a problem before it leads to a major failure is the least you can do. So, we will share the exact tricks for identifying those problems. 

How to Troubleshoot Root Causes of Hydraulic Failures?

Now that you know these problems, you should also know how to identify the root cause of such failures.

Hydraulic system diagnostics is the perfect way to do it. 

Let’s understand the most effective techniques used in hydraulic system diagnostics today.

1. Visual Inspection

Begin with a thorough visual check. Look for:

• Oil leaks around seals, hoses, and fittings

• Cracked or bulged hoses

• Unusual wear on moving parts

• Discoloration around valves and pump areas

This step can identify larger issues, such as fluid contamination or mechanical fatigue.

2. Vibration Analysis

In normal conditions, the motors and pumps in a hydraulic rolling machine generate consistent vibrations. 

This vibration becomes a matter of concern when its intensity changes or increases. It usually signals a mechanical problem like: 

• Bearing failure 

• Shaft misalignment 

• Cavitation.

Pro Tip: A vibration analyzer can help you measure these vibrations and pinpoint worn components before they fail, allowing for timely maintenance and replacement.

3. Hydraulic Fluid Analysis

We’ve already discussed that dirty or degraded hydraulic oil is a common cause of system failure. That’s why Hydraulic fluid analysis is a must.

You should check for:

• Water contamination

• Metal particles from internal wear

• Oxidation levels

• Viscosity breakdown

If the hydraulic fluid doesn’t meet ISO cleanliness codes, it's time for a replacement. 

4. Pressure Testing

Hydraulic systems operate under a specific pressure range. 

Use pressure gauges at different system points to monitor:

• Pump output pressure

• Actuator input pressure

• Return line pressure

This approach will pinpoint the exact location of a failure or blockage.

5. Infrared Thermography

High temperatures are something that can’t be spotted easily.

Thermal imaging cameras can detect abnormal heat zones inside the system, like:

• Excessive friction

• Blocked filters

• Failing pumps or motors

You can extend the component's life once you catch heat-related issues at the earliest.

Pro tip: Follow this machine maintenance checklist to extend your machine's lifespan.

5 Preventive Measures and Maintenance Strategies 

A hydraulic failure can occur for several reasons, some of which we discussed just now. Although you cannot completely avoid such issues, you can take preventive measures to minimize the likelihood of getting into such situations. 

Here, we have listed five of those measures that you can take: 

1. Scheduled Inspections: Regularly check hoses, seals, and fluid levels. Look for wear, cracks, or leaks. 

2. Fluid Management: Always use clean and compatible hydraulic oil. Contaminated or incorrect fluids can quickly damage pumps and valves. 

3. Filtration Systems: Install and replace filters regularly to maintain optimal performance. Dirty oil is the primary cause of internal wear. 

4. System Calibration: Regularly check pressure and flow settings. Incorrect calibration puts extra stress on components and reduces their efficiency. 

5. Operator Training: Train your team to recognize early signs of trouble, such as unusual noises, leaks, or slow movement.

Your Hydraulic System Deserves Expert Care

Your plate rolling machine might be the best one, or it can be an outdated one, too.

But in any of the cases, you’ll require an expert who can take care of:

• Preventive maintenance

• Service and repairs

• Spaces and accessories

• Upgrades and refurbishment 

• Training

At Himalaya Machinery, we provide all these services to you. 

Plus, we manufacture advanced plate rolling machines, so we are here if you need an upgrade.  

We have been in this industry for the last 45 years, so we understand the inner workings of hydraulic systems. 

Connect with us, and we’ll ensure your machine delivers consistent results. 

Hydraulic System Failure Analysis of a Plate Rolling Machine: FAQs

1. What are the 4 reasons behind hydraulic system failure?

Hydraulic system failures generally happen due to:

• Fluid contamination

• Overheating

• Pressure drops 

• Worn-out components like seals or hoses.
  

2. What is the most common problem in a hydraulic system?

The most prevalent issue is fluid contamination. Metal particles or dirt in hydraulic oil can damage pumps, cylinders, and valves, impacting the hydraulic system's performance or even leading to total system failure.

3. What is the principle of a plate rolling machine?

A plate rolling machine applies force through hydraulic-powered rollers to bend and shape metal sheets. The process uses controlled pressure and roller movement to create consistent curves or shapes.