Archives

Using the S.T.A.M.P.E.D. Process to Choose Hydraulic Hoses

Choosing the right hydraulic hose is critical to the safety and lifespan of your hydraulic system. It also requires considering many different factors at once, so the S.TA.M.P.E.D. method is designed to help customers with this process. Learn what this method is and how you can use it to choose the ideal type of hydraulic hose for your application.

What Is the S.T.A.M.P.E.D. Process?

The S.T.A.M.P.E.D. hose acronym represents all the hose attributes you need to know to purchase the right hoses for your hydraulic system. The seven key attributes are:

• S: Size
• T: Temperature
• A: Application
• M: Material/Media
• P: Pressure
• E: Ends
• D: Delivery

The best hose accommodates all seven characteristics. Below, you’ll learn more about each property.

Size

The size of your hydraulic hose consists of four different measurements:

1. Inside diameter (ID): The inner diameter of the hose is the measurement of the straight distance between the two furthest points on the inside of the hose. ID determines the fluid flow rate and the total volume of fluid that can travel through the cross-section of the hose.
2. Outside diameter (OD): OD is the measurement of the straight distance between the two furthest points on the outside of hose, including wall thickness.
3. Overall length: Measure both the length of the hose itself and the attached fittings to determine the total length.
4. Tolerance: Tolerance is important to determine how much variation is allowed for the hose. Some applications or hydraulic systems have stricter tolerance limits than others.

Temperature

Consider both the temperature of the fluid that will move through the hose and the ambient temperature outside the hose. Your chosen hose must be able to handle both the lowest and highest temperatures that your system will experience. If the material cannot withstand the anticipated temperature extremes, it may become brittle, start to break down, or chemically react to the fluid or the outside environment. For example, proximity to hot manifolds can jeopardize the integrity of hose materials not rated for such high heat levels. Depending on the maximum temperatures of the application, you may need to use heat shields as additional protection.

Application

Identify the conditions under which your hose assembly will be used. There are four main categories of applications your specific use case may fall under:

1. High impulse applications: There are frequent pressure spikes that the hose needs to accommodate.
2. Low impulse applications: There are few pressure spikes.
3. Flexing applications: The hose will frequently need to bend or flex.
4. Non-flexing applications: The hose assembly will remain relatively still, with no bending or flexing during operation.

Material

Material refers to the compatibility of the hose material with the fluid being conveyed, including its type and concentration. If your hose needs to convey specialized chemicals or oils, the inner hose tube and cover material must both be compatible with the fluid. All other components in the hose assembly, such as the O-rings and hose ends, must also be compatible with the fluid being conveyed or the environment that the components will come into contact with. Additional considerations include the need for flame resistance (MSHA certification), static wire, nonconductivity, abrasion resistance, and more.

Pressure

Identify the internal and external pressure levels the hydraulic hose assembly will be subject to, including details regarding anticipated pressure spikes or changes. Determine the system’s maximum operating pressure, which will be based on the relief setting. All elements of the hose, including the hose connections/ends, should not be rated below this maximum pressure.

However, sudden pressure spikes can surge above that relief setting and the maximum operating pressure, reducing the overall service life of the hose assembly. So account for those spikes in pressure when choosing a hose.

Ends

The ends refer to the hose’s termination style, type, attachment method, or orientation. Select the right terminations based on your system’s working pressure, required vibration resistance, and other requirements. Always use manufacturer-approved ends and couplings for hose assemblies.

Delivery

Finally, consider any quality, testing, cleanliness, packaging, and delivery requirements you may have. Along with any manufacturer recommendations for maximum fluid velocity, carefully select your hose based on any other special requirements.

Contact Jason Industrial for Hydraulic Hoses

At Jason Industrial, we’re committed to giving our clients the high-quality hydraulic and industrial hoses they need for their unique systems. We offer a wide selection of hoses with different materials, end connectors, certifications, and delivery options, and our expert team is available to answer your questions. Contact us today to learn more about our different products and service options, or request a quote for pricing details.

How to Use the Nomographic Chart to Size Your Hydraulic & Industrial Hoses

Selecting the ideal hydraulic or industrial hose size is critical in delivering the intended performance. In the hose industry, a nomographic chart helps users choose the appropriate hose size based on system fluid volumetric flow rate and fluid velocity. Here, we will discuss sizing for hoses used in the industrial market and guide you through sizing with a nomographic chart.

Size Specifications of Industrial & Hydraulic Hoses

Industrial/Hydraulic hose sizing is specified by inner diameter. Outer diameter (OD) is a measurement of the entire diameter of the hose cross-section, including the diameter of the tube and any covers or reinforcement. The outer diameter takes the hose wall thickness into account, unlike inner diameter (ID) measurements, which only describe the diameter of the inside of the hose. The OD is a critical characteristic to identify the right size fittings and other components for industrial hoses.

Inner diameter is the measurement of the space inside the flow cross-section, and it will affect the flow velocity of the media traveling through the hose. An oversized ID can deliver slower flow, while an undersized ID can result in tube damage, heating of the fluid and the hose, pressure drops, and system damage due to tube failure and premature failure of the hose itself.

Hydraulic Hose Sizing With Nomographic Chart

What Is a Nomographic Chart?

A nomographic chart is a visual tool that allows users to choose the ideal hose size based on system fluid volumetric flow rate and fluid velocity. Users also need to know whether the hose will be used in suction or discharge. Inherent in the design of a standard nomogram is a series of formulas and calculations that users would otherwise need to do without the chart. One of these formulas is the following:

Area (in.2) = 0.321 x gallons per minute (GPM) / Velocity (feet per second)

How to Use a Nomographic Chart

The left-hand column represents flow in gallons per minute, the middle column is the inside diameter of the hose, and the right-hand column represents suction or discharge velocity in feet per second. Once you understand each column, follow these steps:

• Identify the volumetric flow rate required for your system and whether the hose is in suction or discharge.
• Lay a ruler across the chart connecting the flow rate number to the recommended velocity range for suction or discharge.
• Find the intersection points on the middle column to determine what IDs of the hose are recommended within the velocity flow range.

For example, to determine the minimum ID of a hydraulic pressure hose required to transport fluid at a rate of 20 GPM, draw a straight line from 20 GPM on the left side of the chart to the maximum recommended velocity on the right side, which is 15 feet per second. The line should intersect the middle vertical column, identifying a hose with an ID of ¾ in. If the velocity is higher than the recommended range, it could cause issues with the hose, like erosion or degradation of the tube.

On hoses used for return or suction to the intake of a pump, the maximum recommended velocity should not exceed 4 feet per second to avoid pump cavitation and damage to the hose, which leads to system failure.

The above recommendations are for fluids at operating temperatures between 65 °F (18.3 °C) and 155 °F (68.3 °C), and a maximum viscosity of 315 S.S.U. at 100 °F (37.8 °C).

Contact Jason Industrial for Hydraulic & Industrial Hoses

Selecting the right hose for your application requires identifying the appropriate ID, OD, and length. Jason Industrial has been a leader in supplying industrial hoses and power transmission belts since 1958. We have distribution centers throughout North and South America to deliver fast solutions. We also offer couplings, fittings, and accessories to deliver a complete solution for your project. Contact us or request a quote to speak with a specialist about our industrial hoses for your application.