Industrial hose, rubber hose how to identify good or bad?
Hose divided into high-pressure hose and low pressure hose (high and low pressure hose) two, high pressure hose generally from the outer layer of steel wire reinforced layer, the plastic layer and the inner layer of four parts. Hose in the direct contact with the hydraulic oil, generally made of synthetic rubber. The carrying capacity of the hose depends on the reinforcement, which is the skeleton of the hose and is usually braided or wound with steel wire. Most of the high-pressure wire braid used as the skeleton, high pressure, high pressure multi-wire winding skeleton. Hose outer layer is generally made of abrasion-resistant and corrosion-resistant rubber to ensure that the reinforcement layer is not damaged by mechanical damage, chemical corrosion, moisture and rust. Low-pressure hose is made of woven cotton and twine instead of braided steel wire, Oil pipeline.
Hose production with a mixing machine according to the formula mixing the inner layer of plastic, the middle layer of plastic and the outer layer of plastic; Extrusion with the inner layer of the hose, coated with a release agent coated soft or hard core (liquid Nitrogen freezing method may not die); calender into the middle layer of plastic sheeting, plus isolation agent winding and cutting according to the requirements of the provisions of the width; the inner tube with the tube wrapped in a winding machine or braiding machine wound copper wire Or copper wire rope at the same time in the winding machine or weaving machine in the middle of plastic sheet wrapped around each two layers of copper or copper wire rope, winding wire beginning and ending banding (some early winders need to pre-copper wire Pre-stress stereotypes processing); again in the extruder coating the outer plastic, and then wrapped lead or cloth vulcanized protective layer; vulcanized by a curing tank or salt bath curing; finally removed vulcanized protective layer, the withdrawal of the die, Pipe fittings, sampling pressure test.
Inside and outside the high-pressure hose wall are oil-resistant rubber, in the middle (2 to 4 layers) cross-braided wire or wound wire. Poor quality hose will appear: uneven hose wall thickness; tight braid, too loose or too few layers of steel wire; hose deformation after deformation (elongation, shortening or bending deformation) greater; plastic outer Poor air tightness leads to corrosion of the steel wire; poor sealing of the inner rubber allows the high pressure oil to easily enter the steel wire layer; and the adhesion between the rubber layer and the steel wire layer is insufficient. The above situation will reduce the hose endurance, and eventually burst in the weakness of the wall. Assembly, if the amount of buckling is too small, that is, when the pressure between the connector and the hose is too loose, under the action of the hydraulic hose in the early use may be prolapse from the connector; if the amount of overdose, the connector and the hose pressure Too tight, easily lead to local damage to the inner hose, resulting in cracks, high pressure oil will be broken directly into the wire layer, and then along the gap between the wire flew to the jacket tail spray, or have been flew along the wire layer to accumulate , So that the outer plastic drum burst or even rupture. Hose and connector in the assembly, if the buckling speed too fast, likely to cause damage to the inner plastic and steel layer fracture, the hose in use prematurely damaged.
YATAI hose to remind you: In the replacement of high and low pressure hose, the length of the hose used, the number of layers of steel, joint shape and size should be reasonable, and should minimize the hose bending; Tighten the joint nut, do not make the hose Distortion, excessive bending and distortion can greatly reduce the service life of the hose. For some parts prone to friction, protective measures should be taken to prevent the hose from bursting due to abrasion.