Advantages and disadvantages of hydraulic press

Advantages and disadvantages of hydraulic press

(1) Advantages

For the hollow structure with variable cross-section, the traditional manufacturing process is stamping two half pieces first, and then welding them as a whole, while hydroforming can form the hollow structure with variable cross-section at one time. Compared with stamping and welding process, hydroforming technology has the following advantages

1. Reduce quality and save materials. For typical parts such as engine bracket and radiator bracket, hydroforming parts are 20% – 40% less than stamping parts; For hollow stepped shaft parts, the weight can be reduced by 40% ~ 50%.

2. Reduce the number of parts and mold, reduce mold costs. Hydroforming parts usually need only one set of dies, while stamping parts mostly need multiple sets of dies. The number of hydroforming engine bracket parts is reduced from 6 to 1, and the number of radiator bracket parts is reduced from 17 to 10.

3. It can reduce the welding amount of subsequent machining and assembly. Taking the radiator bracket as an example, the heat dissipation area increased by 43%, the number of solder joints decreased from 174 to 20, the number of processes decreased from 13 to 6, and the productivity increased by 66%.

4. Improve the strength and stiffness, especially the fatigue strength. For example, the stiffness of hydroforming radiator bracket can be increased by 39% in the vertical direction and 50% in the horizontal direction.

5. Reduce production cost. According to the statistical analysis of the applied hydroforming parts, the production cost of hydroforming parts is reduced by 15% ~ 20% than that of stamping parts, and the die cost is reduced by 20% ~ 30%.

(2) Disadvantages

1) The manufacturing accuracy of hydraulic components is required to be high. Due to the high technical requirements and difficult assembly, the use and maintenance of hydraulic components are relatively strict.

2) It is difficult to realize constant ratio transmission. Hydraulic transmission uses hydraulic oil as working medium, so it is inevitable to have leakage between relative moving surfaces. At the same time, the oil is not absolutely incompressible. Therefore, it is not suitable to be used in the occasions with strict transmission ratio requirements, such as the transmission system of thread and gear processing machine tools.

3) Due to the influence of temperature, the viscosity of oil changes with the change of temperature, so it is not suitable to work in high or low temperature environment.

4) It is not suitable for long-distance transmission of power. Because the pressure oil is transmitted by tubing, the pressure loss is large, so it is not suitable for long-distance transmission of power.

5) When air is mixed in the oil, it is easy to affect the working performance. When air is mixed in the oil, it is easy to cause crawling, vibration and noise, which will affect the working performance of the system.

6) The oil is easy to pollute, which will affect the reliability of the system.

7) It is not easy to check and remove the fault.

Decho is a professional supplier on hydraulic components ,if you have any request,pls do not hesitate to contact us by email [email protected]

Key points of selection of common hydraulic valves

Key points of selection of common hydraulic valves

The selection of proper hydraulic valve is an important condition to make the design of hydraulic system reasonable, the technical and economic performance excellent, the installation and maintenance simple, and to ensure the normal operation of the system. Because the selection of hydraulic valve is very important to the success of the system, it must be taken seriously.

General principles of type selection

① According to the drag and control function requirements of the system, the function and variety of the hydraulic valve are reasonably selected, and a complete hydraulic circuit and system schematic diagram are formed together with the hydraulic pump, actuator and hydraulic accessories.

② The existing standard shaped series products are preferred, unless it is necessary to design the special hydraulic control valve.

③ According to the working pressure and flow (working flow) of the system, and considering the type of valve, installation and connection mode, operation mode, working medium, size and quality, working life, economy, adaptability and maintenance convenience, source of goods and product history, it is selected from relevant design manuals or product samples.

Type selection of hydraulic valve

The performance requirements of hydraulic system are different, so are the performance requirements of the selected hydraulic valves, and many performances are affected by the structural characteristics. For example, for the system with fast reversing speed, AC electromagnetic reversing valve is generally selected; On the contrary, for the system with slow commutation speed, DC electromagnetic directional valve can be selected; For example, in the hydraulic system, the requirements for valve core reset and neutral energy are particularly strict, and the medium-sized hydraulic structure can be selected; If the hydraulic control check valve is used, and the back pressure of reverse oil outlet is high, but the control pressure cannot be raised very high, the leakage type or pilot type structure should be selected; For the pressure valve to protect the safety of the system, it is required to be sensitive and the pressure overshoot is small, so as to avoid the large impact pressure and absorb the impact of the reversing valve, so the components that can meet the above performance requirements must be selected; If the general flow valve can not meet the accuracy requirements of actuator movement due to the change of pressure or temperature, the speed control valve with pressure compensation device or temperature compensation device should be selected

Selection of nominal pressure and rated flow

(1) Selection of nominal pressure (rated pressure)

The hydraulic valve of corresponding pressure level can be selected according to the working pressure determined in the system design, and the working pressure of the system should be properly lower than the nominal pressure value indicated on the product. High pressure series of hydraulic valves are generally applicable to all working pressure ranges below the rated pressure. However, some technical indexes of high-pressure hydraulic components under rated pressure will be different under different working pressure, and some indexes will become better. If the actual working pressure of the hydraulic system is slightly higher than the rated pressure value indicated by the hydraulic valve in a short period of time, it is generally allowed. But it is not allowed to work in this state for a long time, otherwise it will affect the normal life and some performance indexes of the product.

(2) Selection of rated flow

The rated flow of each hydraulic control valve should be close to its working flow, which is the most economical and reasonable match. The valve can also be used under the condition of short-term over flow, but if the valve works under the condition of long-term working flow greater than the rated flow, it is easy to cause hydraulic clamping and hydrodynamic force, and have adverse effects on the working quality of the valve.

In a hydraulic system, the flow of each oil circuit can not be the same, so the flow parameters of the valve can not be selected simply according to the maximum output flow of the hydraulic source, but should consider the maximum flow of each valve in all design states of the hydraulic system, for example, the flow of each oil circuit in series is equal; The flow of parallel oil circuit working at the same time is equal to the sum of the flow of each oil circuit; For the directional valve of differential hydraulic cylinder, its flow selection should take into account that when the hydraulic cylinder changes direction, the flow discharged from the non rod chamber is much larger than that discharged from the rod chamber, and may even be larger than the maximum flow output from the hydraulic pump; For the sequence valve and pressure reducing valve in the system, the working flow should not be far less than the rated flow, otherwise it is easy to produce vibration or other instability; For throttle valve and governor valve, the minimum steady flow should be paid attention to.

Decho is a professional supplier on hydraulic components ,if you have any request,pls do not hesitate to contact us by email [email protected]

What should be paid attention to when welding lifting rings?

What should be paid attention to when welding lifting rings?

Welding rings in production, its welding is a very important operation, is a test of human technology process.

Matters needing attention in the welding of welding rings:

1. The welded structure can be annealed at a temperature of less than 600 ℃ for stress relief without reducing the working load.

2. Do not cool the welding point quickly.

3. Please check the welding points one by one, without any cracks, dents or scratches. If in doubt, use non-destructive testing methods such as magnetic particle or liquid penetrant testing.

4. If repair is needed, grind the defect clean and carry out qualified welding again.

Attention should be paid to welding materials: according to the electrode manufacturer’s recommendations, welding materials must have tensile strength higher than 70000psi (such as awsa5.1 e-7018). For inert gas shielding metal electricity

The diameter of welding rod is 0.8-1.2mm, according to DIN 8559-sg 3. AWS a 5.18. One of the important points to be reminded is not to weld in open space or in bad weather.

Welding rings of welding temperature influence matters needing attention, need your careful and responsible operation, in order to avoid those trivial trouble, we should pay attention to it.

Decho is a professional supplier on rings and riggings,if you have any request,pls do not hesitate to contact us by email [email protected]

Common materials of rings and riggings

Common materials of rings and riggings

Based on the proper consideration of the use of rings, of course, it is better to choose high quality materials. Therefore, both manufacturers and users attach great importance to this issue. Kosobi is

Professional manufacturers, a variety of non-standard specifications can produce, long screw use

It does not affect the bearing tonnage, and the material used is high-quality alloy steel. The quality of the rings produced is undoubtedly high.

The material and technology of universal rings are comparable with those of foreign brands. The service life depends on what kind of environment you use and how long you use them

Appropriate, not in a humid environment, no load use, as long as you use the correct storage method

Also appropriate, then do not worry about the quality of the rings, durable that is for sure. Tianjin cosobi’s universal rings can rotate 360 degrees and flip 180 degrees, with complete specifications, a large number of goods and high quality

Said, commonly used alloy steel material rings, let you use will be more stable.

Decho is a professional supplier on rings and riggings,if you have any request,pls do not hesitate to contact us by email [email protected]

Classification of hydraulic valves

Classification of hydraulic valves

According to different classification methods, hydraulic valves are divided into many kinds:

1、According to the control method: manual, electric control, hydraulic control, proportional

2、According to function: flow valve (throttle valve, speed control valve, shunt valve), pressure valve (relief valve, pressure reducing valve, sequence valve, unloading valve), directional valve (electromagnetic directional valve, manual directional valve, one-way valve, hydraulic control one-way valve)

3、According to the installation method: plate valve, pipe valve, Superposition valve, screw cartridge valve, cover valve

Decho is a professional supplier on  hydraulic valves , if you have any request , pls donot hesitate to contact us by email [email protected]

Application fields of stamping robot

Application fields of stamping robot

It is an effective method to use stamping robot instead of manual operation to form a fully automatic production line in stamping production.

The overall design of the stamping robot should be considered comprehensively, so as to make it simple, compact, easy to operate, safe and reliable, convenient to install and maintain, and economical. The stamping robots used in industrial production have different structural types and different technical complexity due to different occasions and work requirements. To sum up, there are roughly the following aspects:

1. Automation with single machine: Many high-efficiency special processing equipment (such as various special machine tools, etc.) in production, if auxiliary operations such as loading and unloading of workpieces are continued by manual operation, not only will the labor intensity of workers increase, but also the efficiency of special equipment will not be fully exerted, which will inevitably affect the improvement of labor productivity. If stamping robot is used instead of manual loading and unloading, the above-mentioned unsuitable situation can be changed, the automatic production of single machine can be realized, and the conditions for multi-machine care can be provided. Such as automatic machine tools, automatic loading and unloading manipulators, stamping manipulators, injection molding machines and stamping robots, etc.

2. Forming automatic production line: On the basis of single machine automation, if stamping robots are used to automatically load, unload and transport workpieces, some single machines can be connected into an automatic production line. At present, stamping robots are widely used to realize automatic production in the production lines of shaft and disk workpieces. Such as: automatic production line for shaft machining and its automatic loading and unloading manipulator, automatic production line for machining and its manipulator, loading and unloading manipulator for NC machining machine tools, etc.

3. Automation of high-temperature operation: When working in high-temperature environment (such as heat treatment, casting and forging, etc.), the labor intensity of workers is high and the working conditions are poor, so it is more practical to use stamping robots to operate. Such as automotive leaf spring quenching manipulator, hydraulic press manipulator, etc.

4. Operating tools: Using stamping robot to hold tools and perform automatic operation under high temperature, dust and harmful gas environment can make people get rid of harsh working conditions, reduce labor intensity, improve labor productivity and ensure product quality.

5. Special operations: In modern science and technology, the application of atomic energy, the development of seabed resources, Ad Astra and so on have been familiar to people. However, radioactive radiation, or the seabed, the universe and other environments, are often inaccessible or inaccessible to the human body. Using remote-controlled stamping robots instead of people to carry out such operations can not only complete these special operations, but also work safely for a long time, thus becoming an effective means for human beings to March into new natural fields.

Practice has proved that industrial stamping robot can replace the heavy labor of human hands, significantly reduce the labor intensity of workers, improve working conditions, and improve labor productivity and production automation level. It is effective to use stamping robot for heavy workpiece handling and long-term, frequent and monotonous operation in industrial production. In addition, it can operate under high temperature, low temperature, deep water, cosmic, radioactive and other toxic and polluting environmental conditions, which shows its superiority and has broad development prospects.

Decho is a professional supplier on  stamping robot and stamping automation , if you have any request , pls donot hesitate to contact us by email [email protected]