HIGH PRESSURE STEEL WIRE BRAIDED HOSE

The two designations describe the same architecture: synthetic rubber tube, two layers of steel wire braid, rubber cover. What they do not share is one pressure column. In our table the 3/8 inch (10 mm) code is rated 33 MPa (330 bar) working with 132 MPa minimum burst, while the 5 mm code carries 41.5 MPa. Quote the row you are buying, not the label on the drawing.

Read the bore first. 2SN peaks at 41.5 MPa (415 bar) on the 5 mm code, holds 40.0 MPa (400 bar) at 6.3 mm and exactly 35.0 MPa (350 bar) at 8 mm, then falls to 33.0 MPa (330 bar) at 10 mm and 27.5 MPa (275 bar) at 12.5 mm. A 350 bar circuit therefore rules 2SN out at 10 mm and above. That is where 4SP starts: its 10 mm code is rated 44.5 MPa (445 bar) with 180 MPa burst. At 250 bar, 2SN at 12.5 mm still has headroom.

At 1/2 inch, the 12.5 mm bore code, the table gives 27.5 MPa working (3,989 psi) and 110 MPa (1,100 bar) minimum burst. The inside diameter is held between 12.3 and 13.5 mm, the minimum bend radius on that row is 180 mm, and the body weighs 0.73 kg/m.

60 l/min through a 25 mm bore runs at roughly 2 m/s, which is comfortable for a return line. The same flow squeezed into 12.5 mm runs near 8 m/s: inside the hose, but hard on pressure drop and on the tube. The 1 inch code is rated 16.5 MPa (165 bar) with a 300 mm bend radius, so check the circuit pressure before choosing the larger bore.

On the return, drain, pilot and cooling lines, yes. On the boom and arm rams, usually not: those circuits sit near 35 MPa and pulse hard, while 2SN at 3/4 inch (19 mm) is rated 21.5 MPa (215 bar). The main rams get 4SP. On that 3/4 inch code the 240 mm bend radius is the number that decides whether the hose fits the routing at all.

Yes, and the table is explicit about the limit: the working window is -40 to +100 ℃ on oil, but 0 to +70 ℃ on water-based media. HFC and emulsion duty therefore runs a narrower window than the headline temperature suggests. State the fluid and its temperature and the compound is confirmed before the coil is cut.

Two causes dominate. The first is crimp diameter: an under-crimp leaks, an over-crimp crushes the braid and the wire breaks a few hundred cycles later, and both look fine from outside. The second is routing, because a 3/8 inch line bent tighter than its 130 mm minimum works the braid at the ferrule on every pressure cycle. Measure the real bend on the machine before blaming the hose.

Covers crack on UV and ozone long before the tube fails, and spare coils stored outside are the usual victims. Our cover is a weather- and abrasion-resistant compound, but the practical limits are the ones in the table: continuous service to +100 ℃, and 0 to +70 ℃ where water-based fluid is used. Coils kept under cover age on the braid life, not on the cover.

YIBO, in Luohe, Henan, braids the full range on one line: 12 codes from 5 mm to 63 mm bore, 3/16 inch to 2-1/2 inch, so a mixed order ships as a single lot. The minimum follows the code rather than the order: standard sizes come off stock coils, the 63 mm code is made to order. Send the code list and we confirm which lines are ex-stock.

Price tracks bore, because the body does: 0.33 kg/m at the 5 mm code, 0.73 kg/m at 1/2 inch, 1.44 kg/m at 1 inch, 3.47 kg/m at 63 mm. A 100 m order of 1/2 inch is one 73 kg coil, which is what a freight quote needs to know. Send bore, ends and destination and a firm price comes back the same working day.