We are getting a 3/4" hydraulic hose made for a Kobelco SK250 excavator. What is the pressure rating the hose needs to have? To be more specific, what's the SAE rating of that hose?
Depends on what it's connected to? That's a pretty small hose for that size machine. Brochure lists pressures up to 5,500 psi for the working circuits, in 3/4" hose that would probably call for 100R15 or CAT XT6. If it's not connected to a cylinder (Boom, bucket, stick) post back and you may be able to use something half the price.
Thanks for the info. Its a hose going from a block on the pump to the valve block. In the parts manual its listed under suction delivery. It got a pinhole at the elbow that squirts when the arm cylinder reaches the end of the strokes, so I'm guessing its high pressure.
Huh. That six wire hose is stiff as a board and they weigh it by the ounce, so if that's what you end up replacing it with I would imagine it will last a long time.
An update.... Just by looking, the hoses on the excavator didn't seem heavy enough to fit the 6,000 psi category, so I started looking for a hose where I could read a pressure rating and found 34.5 Mpa which converts to 5,000 psi. The dealer said 4,000 psi will do it, but I'm not settling for less than what's on there. So what would the SAE rating of a 5,000 psi hose be?
Aha... what's on there is probably a DIN hose, 20023, 4 wire. You can use a CAT 1956 (DIN) or a 100R13, or CAT XT-5, they're all rated at 5,000 in a 3/4". Some hose manufacturers will have their own special hoses that fall outside the SAE rating system but still meet the pressure spec which will work fine also.
Thank you. Its all Bridgestone hose and fittings on the excavator.
Don't get much better than that. They use DIN spec which is the metric version of SAE pretty much.