S.T.A.M.P.E.D – the industry wide acronym should be the start of your every conversation when replacing an existing hose or spec’ing a hose for a new application. The easy to remember 7 step guideline is essential as it highlights and defines important characteristics about hoses. Those of you that work with hydraulic hoses are well aware that choosing the right hydraulic hose for your machinery is crucial for smooth flow. Just because the hose looks simple and interchangeable doesn’t mean it is. Hydraulic hose is a multi-layered sophisticated tool developed to meet specific needs.
- Step 1: Size
The inner diameter of the hose must be sufficient to keep pressure loss to a minimum and prevent damages that happen due to excessive disturbance and heat. If the original hose lay-line is illegible, measure the inner diameter for determining the size. Sometimes the outside diameter is a critical measurement as well. If the hydraulic hose is in a confined space you’ll need to match the outside diameter.
- Step 2: Temperature
When choosing a hydraulic hose, consider fluid temperature as well as ambient temperature. The hose you choose must be capable of handling both the maximum and minimum temperature endured by the system.
- Step 3: Application
Application refers to how the hose will be used, and under what conditions. To meet the requirements of the application, some further questions must be answered:
- How is the hose construction like?
- Suction application?
- Fluid compatibility?
- Minimum Bend Radius?
- Thread Type?
- Excessive Abrasion?
- Environmental Conditions?
- Step 4: Material
Material specifies what is being conveyed through the hose. Hose selection procedure must establish compatibility with hose cover, tube, o-rings and couplings with the fluid used. Be more cautious when selecting hose for gaseous applications.
- Step 5: Pressure
Pressure is another very important piece of information you should know in order to select the proper hose. Most hose is made to a 3:1 or 4:1 burst to working pressure safety factor. For example, a 4:1 hose that has a working pressure of 2000 pounds per square inch (psi) would have a burst pressure of 8000 psi, this does not mean however, that you should go over the 2000 psi limit the manufacturer has rated the hose for. The hose should be able to handle the highest pressure the system will see. Using a hose that isn’t rated high enough can cause serious injury or death.
- Step 6: Ends
End connections should be identified using coupling templates or measuring tools. What fittings will go on the end of the hose? What style thread is required to connect the hose to the equipment? In the case of elbows, what is the correct direction of the 45 or 90 degree fittings? Are you using the right metal for the material you are conveying?
- Step 7: Delivery
Delivery is the packaging, testing and delivery requirements. Does the hose need to be pressure tested? Is there a specific way the hose should be packaged to ensure the hose assembly arrives in tact? How quickly does the customer need the hose?
The S.T.A.M.P.E.D system of hose requirements is a critical list when it comes to recommending the correct hose for your customer’s application. These seven steps are essential characteristics to ensure your choosing the right hydraulic hose.