When you order hose and fittings from Parker, remember the word "STAMP." That way you won't forget important information!
Size
Parker uses a system of measurement called Dash Numbers to indicate hose and filting size. The Dash Number, or Dash Size, is the measure of a hose's Inner Diameter (I.D.) in sixteenths of an inch.
This measuring system of the inside diameter of the hose is universally used by the nuid power industry today. Don't know the hose size? Check the layline.
If the original printing has worn off, the original hose must be cut and the inside diameter measured. Be sure to measure the overall assembly length and fitting orientation before cutting the hose.
The hose I.D. must be sized accurately to obtain the proper flow velocity. A flow that's to slow results in sluggish system performance, while a flow that's too high causes excessive pressure drops, system damage, and leaks.
Use the Flow Capacity Nomogram in Section E to determine the proper hose I.D for your application's flow rate requirements.
Temperature
When specifying hose, there are two temperatures you need to identify. One is the ambient temperature, which is the temperature that exists outside the hose where it is being used; the other is the media temperature, which is the temperature of the media conveyed through the hose. Very high or low ambient temperatures can have adverse affects on the hose cover and reinforcement materials, resulting in reduced service life. Media temperatures can have a much greater impact on hose life.
Parker hoses carry different temperature ratings for different fluids. For example, 811 HT hose has a temperature range of -40 degree F to + 257 degree F (-40 degree C to +125 degree C) for petroleum-based hydraulic fluids. However for water, water/glycol, and water/oil emulsion hydraulic fluids, the range drops to a rating of up to +185°F (+ 85°C). Air is rated even lower at up to 158°F (+ 70°C). Some media can increase or decrease the effects of temperature on the hose. The maximum rated temperature of a hose is specific to the media.
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