From construction to manufacturing and drilling, hydraulic hoses are used daily to keep machines running and complete the job. While they serve the simple function of keeping fluids moving between different parts of a machine, they also are not forgotten about or taken advantage of. This week’s blog will guide you through the key points of hydraulic hose sizes, lengths, diameters, and specifications so you can gain insight into this moderately technical world.
Sizing
The size of your hydraulic hose is crucial to ensure your machine's hydraulic system can work well. There are three main hose measurements that you will need to know: the inner diameter (I.D.), the outer diameter (O.D.), and the length.
Inner Diameter (I.D.)
The inner diameter of a hydraulic hose can be pictured as the inside of a slide at the playground or maybe even the inside of a straw you drink your favorite beverage out of. The I.D. mustn't be too large or too small. Having the correct inner diameter of your hose will ensure the fluids going through the hose are flowing efficiently without any jams or slowdowns.
Outer Diameter (O.D.)
This measurement refers to the outermost diameter of the pipe. Like the inner diameter, the outer diameter of the hose also cannot be too small or too large. If either applies, the assembly may not be properly installed on a track or fit through tight, intricate spaces. This is also the diameter in which you must match the right fittings or components. Therefore, like the inner diameter, the outer diameter also plays a crucial role in ensuring systems work properly.
To measure the inner and outer diameters, use a vernier caliper, which you can read manually using the scale or digitally displayed on a screen.
Length
While the length of the hose can seem self-explanatory, it is also critical in ensuring systems are working correctly. Too short of a hose will not connect systems, while too long of a hose can increase the pressure drop in the system. This is because the hose length adds to the head loss due to friction, which leads to potentially less performance from the hose. You can also face issues like extra friction and slackness. When determining the length, look at your system's endpoints and the room needed.
Identification
In some cases, if not displayed using part numbers or other information, you may need to identify the type of hydraulic hose that your operation needs. There are four types, which we will break down into the following:
Single Spiral Suction Hose
This hose supplies oil, water, or other liquids from the reservoir to the pump. It is identified by having one steel wire wound through to keep the hose from collapsing. The spiral feature often allows for extremely high pressures and severe applications.
Single Braid
This hose is typically used in low-pressure applications, 1000 PSI or under. Applications include small utility lifts, return lines, and wet kits on semis and trailers.
Double Braids
Typically used in slightly higher applications than previously, ranging from 2500-4000 PSI. These hoses have good longevity and are used in lawn tractors, skid steers, smaller agricultural equipment, and railroads.
Four or Six Braids
These are your highest application hoses, used for PSI 4000-6000. These options both offer great longevity and are used in larger applications. Industries where you will see these used are in construction, agriculture, forestry, and mining.
Dash Sizes
Lastly, we turn to the infamous hydraulic hose dash sizes. To put it into plain terms, the dash size refers to the inner diameter of the hydraulic hose, displayed in 1/16” increments. It is a shortcut that tells users the size of the hose quickly. An example would be a -6 hose is 6/16”, or 3/8”.
Hydraulics and Iron Wing Parts
Looking for replacement parts for your hydraulic system? We've got you covered! We carry a large range of parts for heavy-duty truck, heavy equipment, industrial, forklift & lift equipment, and more. Our hydraulic inventory includes pumps, motors, cylinders, hoses, fittings, filters, and more! Search our store by part #, description, or manufacturer and easily filter your results!