Hydraulic hoses are essential for modern machinery. As you know, these machines are based on hydraulic systems. These hoses transport high-pressure hydraulic oil from one part of the machine to another. Without them, the hydraulic system cannot operate. However, how to choose a hydraulic hose with right working pressure?
Choosing a hydraulic hose with the right working pressure is crucial. In simple terms, working pressure is the maximum pressure at which hydraulic hoses operate efficiently. If pressure exceeds this limit, hydraulic hoses may leak or not perform optimally. In this article, I will discuss how to select hydraulic hoses based on the right working pressure. So, let’s get started!
What Is Hydraulic Hose Working Pressure?
Every hydraulic hose has its working pressure. If the hose is exposed to pressure beyond its working pressure, it might leak, fail, or get damaged. That’s why understanding working pressure and staying within its limits is crucial.
Working pressure is the maximum pressure a hydraulic hose is designed to withstand. Beyond this limit, the hose may malfunction, leak, and fail. Each hydraulic hose has its own working pressure, typically written in the user manual. It is advised not to use any hose beyond its working pressure, even if the hose is very strong and rugged.
Hydraulic systems have different components. These include a pump, a valve, a cylinder, and so on. When the hydraulic system is active, these hoses transport materials between these components. If the hose is used incorrectly, it may face stress and leak. If this happens, the hydraulic system may not work effectively because hydraulic oil leaks.
That’s why manufacturers mention working pressure. This way, the hose is not exposed to pressure beyond its limit, which helps prevent leakage. Suppose a hydraulic hose has a working pressure of 3500 PSI. Do not use the hose beyond this pressure limit to keep it in good condition. This way, the hose will perform excellently and offer excellent durability.
Working pressure depends on the hydraulic hose’s construction. Some hoses have single-wire braiding. These hoses are not very strong and have low working pressure. In contrast, some hydraulic hoses have multiple steel wire braiding. These hoses generally have high working pressure. If a hydraulic hose’s middle layer has fabric reinforcement, it further reduces the hose’s working pressure.
Working Pressure vs Burst Pressure: What’s the Difference?
Working pressure and burst pressure are two different specifications used in hydraulic hoses. Interestingly, many people treat these two specifications as the same, but they are different.
Working pressure refers to the maximum pressure at which hydraulic hoses can operate safely. Beyond this limit, the hose can leak and may fail. In contrast, burst pressure is the limit at which hydraulic hoses can no longer withstand pressure and can burst. At burst pressure, the hose can no longer withstand the pressure, fails, and is damaged. A hose should never be exposed to burst pressure.
As mentioned above, the hose’s working pressure is the maximum limit at which it can operate safely. However, if pressure goes beyond the working pressure, the hose won’t burst. Instead, it might keep working safely or show some leakage. For example, if the hose has a working pressure of 3500 PSI, it might still operate safely at 3800 PSI. But it is best to keep the hydraulic pressure below 3500 PSI.
On the other hand, burst pressure is the pressure at which the hose would burst if exposed to it. Typically, the burst-to-working-pressure ratio is 4:1. If a hydraulic hose has a working pressure of 2000 PSI, its burst pressure would be 8000 PSI. This means the burst pressure is four times the working pressure. Remember, you should always consider working pressure when using hydraulic hoses.
How to Choose Hydraulic Hose with the Correct Working Pressure?
Selecting hydraulic hoses with the correct working pressure can be tedious. If you choose a hose with the wrong working pressure, it may not fit your specific hydraulic system. In the section below, I will discuss practical steps to help you choose the right hydraulic hose.
1- Determine the Maximum System Pressure
First, you should consider the maximum pressure your hydraulic system can reach. This will help you choose a hydraulic hose that has the highest pressure rating. Remember, some hydraulic systems have a normal operating pressure. However, sometimes the hydraulic system’s pressure can spike. Knowing this spiked pressure is crucial. This means you should know both the normal pressure and the maximum pressure that a hydraulic system can face. Knowing this will help you choose a hydraulic hose with the right working pressure. Choose a hose with a working pressure similar to or higher than the maximum hydraulic system pressure.
2- Choose Required Hose Size
Ensure the hydraulic hose size is correct. The wrong size can affect the hydraulic hose’s working pressure. As you know, a wide range of hydraulic hoses in different sizes is available. When choosing a hydraulic hose, I recommend considering its inside diameter (ID). If the hose diameter is too large, it will reduce flow velocity and increase pressure drop.
In contrast, a smaller ID will result in higher flow velocity and greater pressure drop. The hydraulic oil will flow with more pressure. Always check the hydraulic system’s flow rate when choosing hose size. A hose that is too large would be costly and may not serve its role effectively.
3- Select the Right Hose Construction
Choosing the correct hose construction is crucial. As discussed above, better construction can withstand higher pressure. If you need a hose with high working pressure, choose one with multi-wire braiding. In contrast, if your requirement does not demand high working pressure, a hose with single-wire braiding is suitable. Remember, hydraulic hose construction plays a key role in choosing the right hydraulic hoses. Hoses with multi-wire braiding reinforcement can handle higher working pressures.
4- Check the Manufacturer’s Working-Pressure Rating
Each manufacturer mentions a specific working pressure for each hydraulic hose. You first identify the maximum pressure the hydraulic system faces. Then check the manufacturer’s working pressure ratings. Some hoses might have a working pressure of 2000 PSI, while others can have 3000 PSI or 5000 PSI.
You can then choose a hydraulic hose whose working pressure matches the maximum hydraulic system pressure. Wondering where to find the manufacturer’s working pressure rating? You can check the hydraulic hose’s user manual. That’s where you’ll see the working pressure rating mentioned. This rating must be higher than the maximum working pressure of the hydraulic system.
5- Fittings and Assembly Compatibility
Before deciding, make sure the hose fitting and assembly match the hose’s working pressure. Suppose you choose a hydraulic hose with a working pressure of 3500 PSI. However, the hose fitting and assembly can withstand only 2500 PSI. As a result, the fitting may leak, affecting hydraulic system performance. Choosing the right hose fitting and assembly is as important as choosing the hose itself. An incompatible fitting or incorrect assembly can cause serious issues. In fact, hydraulic hose may not work efficiently if you choose the wrong fitting or assembly.
6- Operating Conditions and Pressure Spikes
When choosing a hydraulic hose, you should consider operating conditions and pressure spikes. As you know, hydraulic systems are used in different machines. These machines can face different operating conditions. These include sudden increases or decreases in pressure, temperature, vibration, and more. These operating conditions can increase the hydraulic pressure, resulting in high spikes.
Therefore, you should consider all the operating conditions of the hydraulic system. This will help you determine the highest (maximum) pressure the hydraulic system will face. Suppose the maximum pressure, even with a spike in the system, is 4000 PSI. In this case, you should choose a hydraulic hose with a working pressure of 4200 PSI. This way, the hydraulic hose won’t have issues even under worse conditions.
Hydraulic Hose Working Pressure Selection Example
Let’s understand the hydraulic hose working pressure with an example. Suppose you have a machine with a hydraulic system of max pressure 4500 PSI. This maximum pressure typically does not include a sudden pressure spike. Therefore, you must consider sudden pressure spikes, operating conditions, vibrations, and so on.
To be safe, you can consider the maximum hydraulic system pressure to be 5000 PSI. Now it is time to choose the right hydraulic hose with the correct working pressure. In the market, you’ll see those with various working pressures. These include 3500 PSI, 5000 PSI, 5500 PSI, and so on. However, you should use a hydraulic hose with a working pressure of at least 5500 PSI.
This hose will perform well and withstand unexpected pressure spikes. You can also choose those with a working pressure of 5000 PSI. But choosing 5500 PSI gives you a 500 PSI buffer. This can save you if your hydraulic system experiences an accident and a sudden, very high pressure spike. A hydraulic hose with a working pressure of 5500 PSI will have a burst pressure of around 22000 PSI.
Factors to Consider When Choosing Hydraulic Hose Working Pressure
As I said above, hydraulic hose working pressure selection can be challenging. However, don’t worry; I’ll give you a simple checklist. If you consider this checklist, you’ll choose the right hydraulic hose with the right working pressure.
| Factor | Importance |
| Maximum Operating Pressure | Very High |
| Pressure Spikes and Surge Pressure | Very High |
| Hose Construction and Reinforcement | مرتفع |
| Hose Diameter and Size | مرتفع |
| Hydraulic Fluid Compatibility | مرتفع |
| Operating Temperature | مرتفع |
| Fittings and Connectors | Very High |
| Pressure Pulsation and Impulse Resistance | مرتفع |
الأسئلة الشائعة
How do I choose the correct working pressure for a hydraulic hose?
Choose the correct working pressure for hoses by knowing the hydraulic system’s maximum pressure. The hose you choose must have a working pressure higher than the maximum pressure of the hydraulic system. This will help you choose the right hydraulic hose for your system.
Should hydraulic hose working pressure be higher than system pressure?
Yes. In most cases, the hydraulic hose working pressure must be higher than the system pressure. This way, your hose won’t be overpressurized. This helps prevent hose leakage. If the working pressure is lower than the system pressure, the hose is more likely to leak.
What happens if a hydraulic hose is rated below system pressure?
I don’t recommend choosing a hydraulic hose that is rated below system pressure. If you do so, your hydraulic hose might malfunction. Leakage is likely when the hose faces pressure that exceeds its maximum capacity. In the worst case, the hose can also be damaged by high pressure.
الخلاصة
In conclusion, hydraulic hoses are a must for a wide range of machinery that use hydraulic systems. However, choosing hydraulic hoses with the correct working pressure is crucial. If you choose a hose with low working pressure, it won’t withstand high pressure. A lower working pressure means the hose cannot withstand high pressure.
In the market, you’ll find hoses with different working pressures. Before choosing any hose, I recommend considering the maximum pressure your system faces. Also, remember that pressure spikes are unexpected in most cases. In this article, I discuss selecting hydraulic hoses based on their working pressures.