Standard for crimping hydraulic hose assembly

Hydraulic hose assembly: It is made of high-pressure steel wire braided or spiral hose and steel fittings that are crimped by special equipment. It is mainly used for hydraulic power transmission or conveying high pressure media such as water, gas and oil under the working temperature of -40°C to +100°C.

Tools/Components

Components: high-pressure steel wire braided hose or spiral hose, hose fittings.

Tools: crimping machine, cutting machine, skiving machine and pressure testing machine.

Methods/Steps

1. Hose cutting: Calculate the length of the hose to be cut according to the total length of the hose assembly to be crimped and the specifications and models of the fittings at both ends.

2. Skiving the outer rubber: Before crimping, it should calculate the skiving length of the outer rubber at both ends of the hose according to the size of the fitting and the ferrule, and mark the position on the hose; then use a knife to skive hose’s out cover to the marked position. There is no spread and damage to steel wire and no damage to the inner tuber of the hose after skiving.

3. Assembly process: Insert the fitting core into the inner hole of the hose, so that the outer shoulder of the outer ferrule and the fitting core ring groove overlap, so as to ensure that the ferule shoulder buckle is pressed into the fitting core ring groove when crimping; When assembling the elbow fitting, the assembly angle should be install as required; Check whether the length of the installed hose assembly meets the requirements.

4. Hose crimping: According to the specifications of the hose to be crimped, select a suitable mold on the crimping machine to crimp the fitting.

5. Pressure test of the hose assembly: Hose assembly is tested by 2 times of the working pressure of the hose as the static pressure. The pressure holding time is 60 seconds, and there must be no abnormal phenomena such as leakage during test.

Precautions

1. The specification and type of the hose need to be crimped cannot be mistaken.

2. The crimping fitting cannot be mistaken.

3. The length of the hose assembly must be correct.

Attachment:

Calculation method of crimping data:

Crimping data = net crimping data + clearance

Clearance = (inner diameter of ferrule - W.D or O.D of hose) + (I.D  of hose - outer diameter of fitting core )

The net crimping data is an empirical value, which is summed up based on the test results. Generally, the crimping is qualified when the core is deformed or the core rod is deformed by an appropriate amount.