Many vehicles, pieces of equipment, and industrial machines use hydraulic hoses. These hoses are generally very durable and reliable, but if you work or drive long enough they will eventually break. In this case, it is best to contact a certified professional who specializes in testing and repairing hydraulic hoses.
Types of Hydraulic Hose Damage
When it comes to industrial hoses, the types of damage fall into four basic categories:
- Damage immediately behind the hose end: Anywhere you have a crimp, or banded connection naturally undergoes more stress when there’s any movement on the hose.
- Local external damage: Such as a scratch, dent, or impact damage.
- Overall external wear due to dragging: For example, in cleaning applications where the hose is regularly moved around and dragged on the ground or concrete. The other cause of external abrasion is simply the constant vibration of the hose in high-pressure applications. The vibrations from the pump cause it to rub on the ground and wear the outer coating. There’s not much that can be done to prevent this kind of damage, it’s the nature of this type of application.
- Long-term use fatigue: When your hose fails because it’s gotten old with use, you know you’ve got the maximum life out of the hose.
Replacing the Crimp
It’s easy to swap out a hose-end – but there are two caveats. First, it shortens the hose length and is therefore only useful for installment payments where you can afford a slightly shorter hose.
Second, especially when attaching a hydraulic hose, it is necessary to have the correct crimp specification. The compression fitting conforms to SAE standards which guarantee the fit between the hose and the end so the hose can withstand the high pressures required. Even the slightest deviation in the connection between the hose and the end can result in performance degradation or worse, be dangerous.
Often, we have people in our shop who want us to crimp to a different type of tubing, but it just doesn’t work. Any decent repair tech will turn you away if they don’t have the right pair. Before you go to the workshop, make sure they have the manufacturer you need in stock.
Making a Break
Hoses are often damaged by impacts, e.g., when a tractor drives over the hose, a rockfall or other types of impact. The easiest way to deal with this type of damage is to cut and repair the hose. There are two ways to cut and repair a high-pressure or hydraulic hose.
The first way is to use a mender by sticking a physical piece into the tubing and crimping it on both ends. The other way to fix a hose is to put two threaded pieces on either side of the splice and put a couple in the middle. Sometimes people try to fix their hoses with duct tape. That might reduce splashing, but with 3000 PSI of pressurized fluid in your hose, the tape is obviously not a safe solution.
The second method is to splice and repair when the damage in a particular spot becomes too great. It’s possible to splice multiple times, although it’s not ideal. Each time you splice and attach a hydraulic hose or other hose, the hose is slightly affected, both in terms of length and the pressure drop of the fluid flowing through the hose.
For basic cleaning applications, that may be fine. But if you’re doing high-pressure splicing for hygiene purposes, you really don’t want to splice more than once. Why? When the function of the hose is reduced, the water pressure decreases and the cleaning time increases.
We’ve seen hoses with as many as six splice and repair connections, which might seem like a money saver, but probably more trouble than it’s worth when you’re doing some serious work.
Look for abrasions and exposed wires
If there is local external damage, a hose can be repaired with a cover repair if you catch the problem early enough. If you immediately take care of a scratch on the cover of a hydraulic or high-pressure hose, you can protect the reinforcement. All hoses have a protective sleeve which ensures that the internal reinforcement wire is not damaged.
However, if you ignore scratches or dents, they can corrode, resulting in either a full replacement, splicing, or repair. If you see abrasions or exposed wires and are trying to prevent a full replacement, you can add plastic coil protectors, metal coil protectors, or plastic abrasion-resistant sleeves to protect the damaged area. It is important that you protect the rebar wires from additional abrasion and corrosion.
Long shot saves
Situations, where you need to have your hose repaired immediately, are common. Maybe your equipment stopped mid-production or during harvest and you can’t wait for a new part to arrive. We understand. If it’s urgent, we’ll find a way.
For example, sometimes a hose and fitting are not the same sizes. If there’s a small jump, say from 1 inch to 1.5 inches, we can find an adjustment to reduce the size, but if it’s a big jump, like from 2 inches to half an inch, there is a big discrepancy.
In an emergency, we adopt a system with several jumps from larger to smaller or from smaller to larger. It’s not ideal, but if you’re really in a pinch, this is a fix that will work, at least temporarily, until the system could be reconfigured.
How To Repair Hydraulic Hose?- Step by Step
However, in a pinch, you may need to do an on-site repair until you can reach a professional. Temporarily attaching a hydraulic hose isn’t as daunting a job as you might think. Once the process is broken down into six steps, repairing it can be pretty straightforward.
1. Identify the Correct Hose
Most heavy equipment can perform multiple functions (i.e. lift, push, pull, or cut), and each of these functions may require a different minimum pressure tolerance. For this reason, there can also be different types of hydraulic hoses with different minimum pressures for a single device.
Therefore, it is always best to determine which specification the hose in need of repair must meet. In most cases, the tubing will be made to a specific length and you will need to insert a shorter assembly to make up for what will be cut away during the repair.
Be aware that it is extremely dangerous to replace the wrong hose, even temporarily. All hydraulic hoses must indicate the minimum operating pressure and maximum burst pressure on the hose. If in doubt, contact a trained professional.
2. Remove the Damaged Area
Once you have completed Step 1, you will need to cut out the damaged area of the tubing. Also, if the only problem is that the coupling at the end of the hose is leaking, you will have to cut off the broken end. Thoroughly clean the area around the cut end of the hose. Clean the area of dust, dirt, or other contaminants as these could contaminate the hydraulic fluid.
Even a tiny smudge of dirt can damage internal components and lead to costly failure. Therefore, it is important to ensure that both the fittings and the cut hose ends are clean before proceeding with the remainder of the repair.
3. Use an Adapter to Complete the Installation
In some cases, a hydraulic adapter is required to complete the installation of a repaired hose. Since it is not always possible to carry every type of hydraulic coupling, an acceptable solution is to have a kit with a variety of adapters. If necessary, install the adapters in the appropriate ports and ensure that a secure connection has been made.
Proper tightening (or tightening) of adapters and couplings is an essential part of the repair process. Over- and under-torques can have a detrimental effect on the hydraulic system. If you are unsure how much torque to apply, contact the system manufacturer or a trained professional before proceeding.
4. Confirm the Correct Length
Next, put the hose assembly in place, making sure it is long enough. An overstretched or poorly routed hose is subject to additional pressure and fatigue. Although it’s better to have too much tubing than too little.
It is ideal to have the right length that allows for proper laying in accordance with NAHAD and manufacturer guidelines. Hydraulic systems are constantly under pressure, and too short a hose is more prone to dangerous (and costly) failures.
Make sure the hose is properly routed once it is the correct length. This allows the rest of the hydraulic system to function normally. Many devices use angled fittings to route their hoses and allow the hydraulic oil to flow more freely.
If an angled adapter or coupling is required, install the angled fitting first to ensure correct positioning. Once the angled adapter is in place, the end of the hose assembly can be screwed onto the adapter or connector.
5. Ensure a Proper Seal
Thread the remaining end of the tubing onto or into the opposite opening, making sure that it is properly sealed. Even a small gap or imperfection in the seal can cause problems for the hydraulic system. Check the seal for leaks before continuing
Remember that the seal should be secure, but not too tight. Never twist or tighten the hose while attaching it. Tighten the fitting with a wrench, being careful not to overtighten the gasket.
6. Circulate Fluid at Low Pressure to Check for Leaks
Finally, turn on the hydraulic system and circulate the oil or hydraulic fluid at low pressure. This makes it easier to identify potential leaks and damaged connections. By circulating the hydraulic fluid under low pressure, the remaining air is also flushed. Air in the system can affect performance or damage pumps and other sensitive components.
Let the hydraulic system run for a few minutes and then check again for leaks. Never use your hand to check for leaks as this could result in injury from fluid injection. Use cardboard or a sheet of paper instead. It may take a few minutes for a leak to become visible. Therefore, always check the system before driving the vehicle or using the machine.
Simple repairs to your hydraulic hoses aren’t as difficult as you might think. However, it is recommended that you have your work checked by a professional. This will help ensure that no mistakes have been made and limit the occurrence of future problems.
If you suspect a hydraulic hose is leaking or otherwise damaged, act quickly and make any necessary repairs or replacements immediately. Leaving a leak unattended and not repaired can seriously damage the entire system and leave a large hole in your wallet.
Whether you are working with a farm tractor, delivery truck, or industrial machine, the integrity of the hydraulic system is only as good as the quality of the hose.