Choosing the Correct Hydraulic Hose

Any hydraulic system relies on having quality hoses to continue working effectively. That means selecting the right one could make the difference between operating an effective system or dealing with defects and potential damage. 

When looking at hydraulic hoses, they appear relatively simple and possibly even interchangeable. However, hoses are actually multi-layered, sophisticated tools designed and manufactured for specific applications. Figuring out which hose is right for your system depends on several key factors, including size, temperature, compatibility and choosing the right hose fitting connection.

Choosing a Size

If a hose is to function optimally, the inside diameter must accommodate the correct amount of hydraulic fluid, minimize pressure loss and avert heat generation or excessive turbulence, both of which can damage the hose. The “Dash Numbers” measuring system is the hydraulics industry standard used to indicate hose size and the proper accompanying couplings.

Determining Your Temperatures

When looking for a hose, it will need to be able to accommodate two temperature areas — that of the hydraulic fluid and that of the environment in which the hose exists (ambient temperature). Hoses that cannot withstand both the minimum and maximum temperatures of the fluid, as well as those not designed to work near hot manifolds, are likely to fail.

Ensuring Compatibility 

Typically, replacement hoses should be duplicates of the original hoses. In some circumstances, however, using a different type of replacement hose might actually be desirable. This is especially true if the hose failed prematurely due to excessive abrasion, unusual mechanical loads, routing challenges, temperature fluctuation or some other environmental factor. With advancements in hose engineering, there may be a better hose available.

As you read in the first paragraph, typical hydraulic hoses consist of numerous tubes, including one inner, one outer and several reinforcement layers. Hose tubing must come in direct contact with the fluid it carries, so it is important to ensure that the inner tube is compatible with the system’s fluids in order to perform reliably. Furthermore, the threads and mechanical interfaces of ends and couplings need to be compatible with the hoses and other system components. If they’re not, leaks and other hose failures can occur.

Choosing the right hose fitting connection 

The most important factor in choosing a replacement hydraulic hose is the system pressure. It is vital that you know your system’s precise working pressure — including pressure spikes — when choosing a hose to ensure it will function properly. Finding the correct hose tube and the right fittings will help you avoid future hydraulic hose failures, which may include leakage, cracking or whipping.

Delivery of hydraulic fluid is all about volume and velocity. Any replacement hose needs to be properly sized to efficiently and effectively transport hydraulic fluid. If for any reason the system has been altered, you need to determine the hose I.D. by consulting with an expert.

For more information about hydraulic hoses, or if you need assistance choosing the right hose fitting connection for your system, contact us today!

Why Do Hydraulic Cylinders Fail?

Hydraulic cylinders are used in many industrial applications including a variety of manufacturing equipment and engineering vehicles, or civil engineering equipment. Hydraulic cylinders may encounter challenges for a variety of reasons. Regular equipment inspection, and a good preventive maintenance plan will help decrease the chances of cylindrical failure due to the following reasons:

  • Seal Leakage: One of the most common reasons we see cylinder failure is due to seal leakage. This can be caused by a variety of reasons, from something as simple as an incorrect fitting to inappropriate metalwork clearances. Some other causes of hydraulic cylinder seal leakage might be something like markings on seal grooves or corrosion.
  • Contaminated Fluid: Fluid contamination is another major reason for the cylindrical failure. Abrasive particles that are trapped in a contaminated fluid can bring severe damage to the piston rod or seal surface. Airborne contamination is usually induced by a faulty wiper seal.
  • Damaged Rod Bearings or Piston Rods: It is also common to see damaged rod bearings or piston rods that lead to hydraulic cylinder failure. This is caused due to improper alignment between load and the cylinder, thereby resulting in a bending, or side loading.
  • Internally Corroded Barrel: Contaminated fluid inside a cylinder can lead to internal corrosion. This can be avoided by blocking the water ingress inside the cylinder. However, it may be a sign that cylinder is being used in an environment, where it should not be used. It’s important for an expert to determine what the cause of the corrosion is and how it should be remedied. 
  • Broken Eye Bearing: If a cylinder handles loads above its specification, you may encounter a broken eye bearing.  These may also be caused by a shock loading or a sudden impact due to high pressure.
  • Extreme Temperatures: This factor may affect hydraulic cylinders  by limiting the choice of seal geometries or materials. It can also cause less lubrication and/or seals with cracked sides or brittle appearance.
  • Chemical Contact: Certain chemicals can cause cylinder failure when they come in contact with the seal. While verifying beforehand can prevent this, it is often forgotten, leading to compatibility issues and numerous problems. 

There are various other reasons for a cylindrical failure ranging from high pressure conditions to side loading and more. However, if you notice any symptoms of hydraulic cylinder failure, you can immediately contact an expert preventative maintenance service such as Yarbrough Industries.