Diagnosis Method of Hydraulic System Failure of Forklift

The hydraulic system is the core of the manual hydraulic forklift. In that way, if there is a malfunction in daily use, how should we check and diagnose it. Today, I will introduce you to three basic methods.

1. Visual inspection method

For some relatively simple faults, we can inspect parts by means of sight, hand model, ear hearing and smell.

For example, visual inspection can find faults such as cracks, oil leakage, loosening and deformation. In order that parts can be repaired or replaced in time. Holding oil pipes (especially rubber pipes) by hand, there will be vibration when pressure oil flows through; but there is no such phenomenon when there is no oil flow or the pressure is too low.

In addition, hand touch can also be used to judge whether the lubrication of hydraulic components with mechanical transmission parts is good.

Feel the temperature change of the component housing with your hands. If the component housing is overheat, it means that the lubrication is poor. Ear listening can determine the point of failure and the degree of damage.

For example, hydraulic pump suction, overflow valve opening and component issuance will produce abnormal sounds such as water impact or “water hammer sound”. Some parts will emit peculiar smell due to overheating, poor lubrication and cavitation. We can use nose sniffing in this condition.


2. Replacement diagnosis

We can use this method when there is a lack of diagnostic equipment at the maintenance site, or the components are more precise and not suitable for disassembly. Firstly,  remove the component suspected to be malfunctioning.

Secondly, replace it with a new one or another component of the same model that works normally on the machine for testing.

And then the diagnosis can be made by seeing whether the fault can be eliminated. Although this method is restricted by the structure, on-site component storage or disassembly inconvenience and other factors.

Besides, it may be troublesome to operate. However, it is convenient to use this method for components that are small in size and easy to disassemble, such as balance valves, overflow valves, and one-way valves.

The replacement diagnosis method can avoid the performance degradation of hydraulic components due to blind disassembly.

If you do not use this method for the above failures, and directly remove the suspicious main safety valve and disassemble it.  Its performance may be affected after re-installation, if there is no problem with it.

3. Instrument inspection method

The instrument inspection method is to judge the fault of the system by measuring the pressure, flow and oil temperature of each part of the hydraulic system.

In general on-site inspections, the failure of the hydraulic system is often manifested as insufficient pressure, which is easy to detect. While the detection of flow is more difficult. The size of the flow can only be roughly judged by the speed of the actuator. Therefore, in-field testing, we can use more methods to detect system pressure.

Yide casting is a leading casting foundry in China, with 27 years’ experience, produces top quantity forklift parts. If you are interested in our casting fitting, please send us a drawing file, and feel free to get a quite quote.

How to Choose, Install and Maintain Ductile Iron Pipe

How to Choose, Install and Maintain Ductile Iron Pipe

Firstly, let’s see why choose ductile iron pipe.

In building construction, especially the construction of urban water supply pipeline network, the pipeline products used require high strength, high toughness, strong corrosion resistance and comprehensive cost of construction and installation. From these perspectives, ductile iron pipe is undoubtedly the best choice. From the production process of ductile iron pipe to the final construction and installation, it meets our requirements. No matter how complicate the project, choosing ductile iron pipe as the main pipeline product is definitely a wise choice with the highest cost performance in the long term.

Secondly, the installation of ductile iron pipe mainly includes the following steps:

1. Site selection

Select the installation route of the ductile pipe from the perspective of soil quality and nearby pipelines, and form construction drawings. Special attention should be paid to avoid some corrosive and unsafe installation routes.

2. Pipe laying

Use Large-scale equipment such as excavators and hoisting machines in the pipe laying process. At the same time, a 10-meter ductile pipe should arrange 2 to 3 workers based on experience. The rubber ring should be placed in the socket groove and compacted by hand.

3. Determine the distance of the pipeline

The key of this step is to cut off the iron pipe if it’s too long. And process the spigot end into a groove shape according to the construction angle to facilitate application.

4. Tube body measurement

Through the measurement of the tube body, to demtermine the straight line space and the corner space formed by the installation radian, vacancy, and transfer. Thus in order to achieve stability and avoid displacement.

5. Positioning marking

The purpose of the positioning marking is to achieve that the fixed pipe and moving pipe axis lines are on the same straight line as a wheelbase. This step is to ensure the quality and speed of the installation. Also it helps to prevent the pipeline apron from falling off and affecting the quality and progress.

6. The installation of pipes should be flat, and the pipes should be in a straight line. Besides, be careful of inclination angle.

7. Align the interface of the connecting pipe with the socket. If the insertion resistance is too large, do not insert it forcibly to prevent the rubber ring from twisting.

8. When pipeline installation and laying works are interrupted, use its cap to close the pipe opening to prevent dirt, sand and other debris from entering the pipeline.

9. Cover the middle part of each pipe with soil before the pressure test.

Then, how to maintain ductile iron pipes? Let me introduce to you briefly.

The maintenance of the ductile tube should always start from its selection. Before the project starts, we should perform a visual inspection of the parts, such as pipe fittings, aprons, elbows, etc., so as to avoid using defective parts.

The second point of maintenance is to check and acceptance check. We should pay attention to the socket apron lower tube (pipe) that affects the long-term stable operation, and strive to have no debris in the socket in these aspects. The rubber ring has been hit by a rubber hammer without warping and twisting, and is evenly stuck in the groove.

During the maintenance process of ductile iron pipes, since the axis of the moving pipe is deeply buried in the ground, be careful when there is an inclination angle. If the resistance is too large, do not excavate forcibly to prevent the rubber ring from twisting. The maintenance of ductile tubes in winter also needs preheating with hot water to reduce the hardness and install quickly.

In addition, if the quality of the ductile iron pipes used in the project absolutely meets the national standards, then we should pay attention to the apron, welding, etc. AC and DC. As long as the ductile cast iron pipes are applied properly and the product quality is excellent, it can reduce unnecessary troubles in installation projects. Also, as a new type of pipe material, its future maintenance work is relatively easy.

Yide casting is a leading casting foundry in China, with 27 years’ experience, provides quality duction iron pipe, brass pipe in a big production, OEM service is available, if you are looking for a casting supplier, please don’t hesitate to contact us. Of course, you are welcome to visit our casting factory in China.