Ensuring the right fitting size for your hose is crucial. In our latest blog, we cover five key steps to accurately measure a hydraulic fitting.

Before choosing a hydraulic fitting, it’s essential to verify that its threads will match your selected hose. Properly measuring and identifying fittings is straightforward with the right tools, including ID/OD calipers and thread pitch gauges.

Accurate Automotive Lift Repair Tampa Florida measurements help prevent leaks and downtime. Even for professionals, two fittings can appear identical but differ significantly. A misfit might seem to work initially but can cause long-term issues in your system.

1) Measure Thread Length  

Using a Automotive Lift Repair Tampa Florida thread pitch gauge, place the gauge teeth against the threads until a snug fit is found, ensuring no gaps. For worn fittings, it’s best to use new ones for accurate results. Manufacturers often provide thread identification charts, so match your measurements accordingly.

2) Measure Outside Diameter (Male Thread)  

Use calipers to measure the outside diameter. Zero out the calipers, secure the fitting between the jaws, and close them to get a tight hold. A Vernier caliper provides the most accurate reading—measure multiple times to ensure accuracy.

3) Measure Inside Diameter (Female Thread)  

Measure the inner diameter using Automotive Lift Repair Tampa Florida calipers by placing the jaws inside the fitting for a precise reading.

4) Check Thread Pitch  

Use the thread pitch gauge to determine the distance between threads. Match your measurement to a size chart. If you don’t have a thread gauge, you can estimate by counting the number of threads within an inch. For British and European threads, this is measured in threads per inch, while metric threads gauge the distance between threads.

5) Measure the Angle  

A protractor helps measure the angle of the fitting. The angle is a critical factor in selecting the right fitting, with common angles being 45° and 90°, and sometimes 22.5° on elbow fittings.

Additional Considerations  

Remember, wear and tear can alter the measurements of old fittings, so getting a professional opinion can be helpful. It’s also important to familiarize yourself with common connector types such as NPTF, SAE, ISO, and DIN to aid in accurate fitting identification.

 Hose Pros 101

 Automotive Lift Repair Tampa Florida Hose Construction

A hose typically consists of three components: a tube, reinforcement, and a cover. Technically, if there is no reinforcement, it is referred to as a tube or tubing, which is common with plastics. However, if it has reinforcement, it qualifies as a hose, which is our focus in this article.

Hoses are generally categorized into five types: hydraulic, industrial, metal, Teflon (PTFE, fluorocarbon tube), and composite. The classification of metal, Teflon, and composite hoses is based on their construction. Metal hoses are made entirely of stainless steel or other non-corrosive materials, Teflon hoses consist of Teflon, and composite hoses are constructed from distinct, individual layers.

 Hose Construction Breakdown

Tube  

Starting from the inside, the Automotive Lift Repair Tampa Florida tube is designed to convey materials, so it must be chemically compatible with its contents and capable of withstanding specific temperatures and pressures. It should also be nearly impermeable, as all materials exhibit some level of permeation over time. For instance, while car tires hold air for extended periods, they still require periodic refilling due to gradual air loss. Metal hoses are closest to being impermeable, with certain plastics also performing well.

Reinforcement  

The reinforcement serves as the backbone of the hose, providing strength and pressure capability. It comes in various shapes, sizes, and materials, with high tensile steel wire, textiles, and synthetics being the most common. Specialty materials, like Kevlar, are also used. The reinforcement is wrapped around the hose in braided or spiral configurations, allowing it to withstand both radial and axial pressure.

Braided and spiral reinforcements enable the hose to carry positive pressure, while a helix—made of metal or hard plastic—helps maintain the hose’s shape during negative pressure situations, particularly in suction applications.

Cover  

The Automotive Lift Repair Tampa Florida cover, which is applied over the reinforcement, protects it from abrasion and corrosion. It must endure external temperatures, abrasions, impacts, ozone, industrial chemicals, and other potential hazards. For example, a small nick in the cover of a hydraulic hose might seem insignificant at first, but it can lead to severe corrosion of the steel braid over time, resulting in a failure at the damaged point.

Covers can also be enhanced with fiberglass and silicone sleeves for temperature resistance or plastic and steel wraps for abrasion resistance. It’s crucial to consider all environmental factors that could damage your hose, and the cover serves as its primary defense. If off-the-shelf options are insufficient, we can add additional protective layers.

Metal and Teflon hoses typically do not have covers by design, as they use stainless-steel braid reinforcement, minimizing corrosion concerns. However, don’t let the metal exterior mislead you; the wires are quite thin, often around .015 inches. If a metal hose drags on concrete and wears down those wires, it will likely fail at the point of contact.

ID / OD  

Hoses are defined by their inside diameter (I.D.). For example, a 1-inch hose has a 1-inch I.D., which when measured with calipers, should be close to 1.00 inches. This differs from industrial materials like pipe and tube; for instance, a 1-inch pipe has an I.D. of approximately 1.05 inches for Schedule 40 and an O.D. of about 1.315 inches.

The O.D. is crucial because, along with the I.D., it indicates the hose’s wall thickness. Wall thickness is essential for determining crimp diameters in industrial hose assemblies, where fabrication combines science and artistry. The crimp size can vary even on the same hose assembly due to inconsistencies in wall thickness. Notably, hydraulic hoses require precise and consistent measurements, as crimp diameter specifications typically have a tolerance of ±0.005 inches.

 A Hose for Every Application

Upon reviewing Automotive Lift Repair Tampa Florida hose catalogs, you’ll quickly notice a vast array of hoses for nearly every application. Hydraulic hose catalogs feature textile and steel reinforced constructions—single wire, double wire, four-wire, and six-wire options—along with rubber compounds for high heat, Arctic conditions, and corrosive hydraulic fluids.