Poor manufacturing quality
(1) high pressure hose wall inside and outside are oil-resistant rubber, the middle (2 to 4 layers) cross braided steel wire or wound wire. Poor quality of the hose will appear: hose wall thickness uneven; wire weaving too tight, too loose or wire layer is too small; hose deformation after deformation (elongation, shortening or bending deformation) larger; Poor air tightness lead to corrosion of steel wire; inner plastic seal is poor and make high-pressure oil easily into the wire layer; glue layer and the wire layer adhesion is insufficient. The above situation will make the hose to bear the force to reduce the final weakness in the wall there burst.
(2) hose and joint assembly when the amount of buckle and buckle speed improper selection, or connector structure and material, size selection unreasonable, can lead to hose and joint pressure too tight or too loose, resulting in early damage to the joints.
Assembly, if the buckle pressure is too small, that is, between the joints and hose pressure too loose, the role of oil in the early use of the hose may be out from the joint; if the buckle is too large, the connector and hose pressure Too tight, easy to cause the inner layer of the hose by local damage, resulting in cracks, high pressure oil from the rupture directly into the wire layer, and then along the gap between the wire to the tail of the jacket, or has been along the wire layer to a place to accumulate , So that the outer glue to produce drums or even rupture. Hose and fittings in the assembly, if the buckle speed too fast, likely to cause damage to the inner rubber and wire layer fracture, so that the hose in the use of premature damage.
(3) In addition, the connector design is unreasonable, poor processing quality, can also cause damage to the inner rubber; if the joint material selection improperly, in the process of easy to buckle deformation, thus affecting the quality of the buckle, hose life shortened.
In the quality of the premise, if used improperly, will greatly shorten the hose to the service life. In practice, most of the high-pressure hose damage is due to improper use caused.
(1) by frequent, severe pressure shocks. High pressure hose burst, generally not due to bear too much static pressure caused by, but with the severity of the impact of pressure and the number of times. Engineering machinery in the operation, the tubing will repeatedly appear in the sudden rise or fall of oil pressure situation, which constitutes a frequent pressure on the tubing impact, resulting in the Department of oil seal damage increased, hose blistering and rupture and loose joints Leakage phenomenon. So in operation, the stem of the pull can not be too much, must be gentle.
(2) the use of oil temperature is too high. Construction machinery operation, the hydraulic system due to power loss and make the oil heat, coupled with the impact of external temperature (especially in the summer), can make a sharp increase in oil temperature. The higher the temperature of the oil, the easier the rubber to deteriorate, the elasticity deteriorates, the strength and the sealing performance drop, and the hose will burst quickly. Therefore, in the operation, when the hydraulic system temperature rise is too high, too fast, it should promptly identify the reasons, to be excluded; summer operations, especially in continuous operation, should take the necessary cooling measures.
(3) hose selection, installation is unreasonable. When replacing the high-pressure hose, the length of the selected hose, the number of wire layers, the shape and size of the joint should be reasonable, and should minimize the degree of hose bending; tighten the joint nut, do not make the hose distortion, excessive bending and Distortion will greatly reduce the service life of the hose; for some parts prone to friction should take protective measures to prevent the hose burst due to wear and tear.