Choosing the wrong hose not only carries serious safety risks but can also result in preventing premature failure and expensive downtime. To avoid these issues, get it right the first time. Use the STAMPED acronym to make sure you get the right hose assembly.
STAMPED stands for:
Size
Temperature
Application
Material
Pressure
Ends
Delivery
Here’s a look at each of these critical areas of information that you’ll need:
Understand dash numbers. This is a measuring system specific to hydraulics. The dash indicates the hose I.D. in sixteenths of an inch, though there are exceptions, as noted in the table.
Hydraulic hose identification
All hoses except transportation and refrigerant hoses* |
Transportation and refrigerant hoses** (hose I.D. is equal to O.D.) |
|||
Dash no. |
Inches |
Millimetres |
Inches |
Millimetres |
-2 |
1/8 |
3.2 |
-- |
-- |
-3 |
3/16 |
4.8 |
-- |
-- |
-4 |
1/4 | 6.4 |
3/16 |
4.8 |
-5 |
5/16 |
7.9 |
1/4 |
6.4 |
-6 |
3/8 |
9.5 |
5/16 |
7.9 |
-8 |
1/2 |
12.7 |
13/32 |
10.3 |
-10 |
5/8 |
15.9 |
1/2 |
12.7 |
-12 |
3/4 |
19 |
5/8 |
16 |
-14 |
7/8 |
22.2 |
-- |
-- |
-16 |
1 |
25.4 |
7/8 |
22.2 |
-20 |
1 1/4 |
31.8 |
1 1/8 |
28.6 |
-24 |
1 1/2 |
38.1 |
1 3/8 |
34.9 |
-32 |
2 |
50.8 |
1 13/16 |
46.0 |
-36 |
2 ¼ |
57.6 |
-- |
-- |
-40 |
2 1/2 |
63.5 |
2 3/8 |
60.3 |
-48 |
3 |
76.2 |
-- |
-- |
-56 |
3 1/2 |
88.9 |
-- |
-- |
-64 |
4 |
101.6 |
-- |
-- |
-72 |
4 1/2 |
115.2 |
-- |
-- |
* SAE100R5, SAE100R14, SAEJ51 and SAEJ2064
** SAE100R5, SAE100R14, SAEJ51 and SAEJ2064 only (hose I.D. is equal to O.D.)
What you should know:
Temperature in this context refers to the fluid being used and its environment. You must consider these factors:
When exposed to extreme hot or cold, hoses with a rubber inner tube and/or cover can have significant change in properties. These conditions may require some hoses to be rated to a lower operating pressure.
This refers to the temperature of the fluid being conveyed inside of the hose during use.
Think about the temperature of the hose assembly’s environment.
What is the highest temperature that the fluid or environment might reach, even in short durations? The hose you choose should be rated at or above the maximum ambient and maximum fluid temperature.
What is the lowest temperature the hose assembly will endure? For a hydraulic system, consider the minimum ambient temperature. Make sure your hose is rated at or below the minimum ambient temperature of the assembly’s environment.
Note that maximum assembly working pressures will decrease as temperatures increase.
This is about the conditions of use. The hose assembly you use will be determined by its application, which may be:
Other points to consider:
In addition to the points above, ask yourself these questions:
– Abrasions?
– Vibrations?
– Oil, and if so, which type?
– Acids?
– UV rays?
– Salt water?
Material or media, as it’s also called, refers to what is flowing through the hose, the type and the concentration. The hose inner tube and cover material must be compatible with the conveyed material you’re using. That’s not all. Every component of your hose assembly – ends, O-rings, for example – must be compatible with the material you’re using.
Note, concentration, pressure, and temperature can impact the compatibility of the hose and fluid.
The result of failing to ensure compatibility is permeation, or effusion. This happens when a substance moves through the hose tube walls, causing the hose to degrade, blister and possibly worse. This is especially a problem if the material being conveyed is compressed gas.
Knowing your system pressure, including pressure spikes, is critical when selecting a hose. Here’s what you need to know:
Maximum Operating Pressure
What is the maximum pressure that your system will be subjected to in normal operating conditions? Determine the pressure by the system’s relief setting. Make sure the hose and hose end are not rated to a pressure less than the system’s maximum operating pressure.
Pressure Spikes
This refers to termination end style, type, orientation and your attachment methods.
This isn’t just about receiving your hose assembly. Follow manufacturer recommendations for the hose’s maximum fluid velocity. Too much fluid velocity can result in excessive pressure loss, heat, the hose moving or whipping, and system noise.
Contact: David Song
Phone: 8615376198599
Tel: 053187101088
Email: hxl@huachen.cc
Add: Room 603,Xinsheng building 2#, Xinluo Road, Gaoxin district, Jinan, Shandong province, China