Current situation and development direction of hyd

Current situation and development direction of hydraulic parts of agricultural excavators

current situation and development direction of hydraulic parts of agricultural excavators

information on China's construction machinery

Guide: the development of agricultural excavators in China originated in the mid-1990s and began to rise in 2000. With the construction of new rural areas as the focus of our government in recent years, agricultural excavators have achieved unprecedented development. By 2006, the output had reached about 100000 units, It also gave birth to industries like Yugong machinery and rhinoceros heavy industry

the development of agricultural excavators in China originated in the mid-1990s and began to rise in 2000. With the construction of new rural areas as the focus of our government's work in recent years, agricultural excavators have achieved unprecedented development. By 2006, the output had reached about 100000 units, and also gave birth to representatives of excellent agricultural excavators such as Yugong machinery, rhinoceros heavy industry, Hengte heavy industry, Yituo Shentong company, Fulin machinery, Huaxin heavy industry and so on, Their development witnessed the development of agricultural engineering machinery. Ruilong visited most of their enterprises in August 2006 and May 2007 to understand their needs and development, and the current situation and future needs of hydraulic parts in this industry

I. current situation of agricultural excavators

1. The price of a simple 180 ° deflection wheel excavator is between 55000 and 90000 yuan. Such products are mostly equipped with four legs, or two legs at the rear end, and a bulldozer at the front end

the production of this product will further increase. With the further desire for quality and cost, fierce competition will make many small factories disappear, and the scale of large factories will further increase

2. Digging loader

as the name suggests, it is digging one end and loading the other, and the price is about 95000~11000

because this kind of product has two functions of mining and loading, it has a wider range of applications, so the production volume will increase rapidly

3. The full rotary wheel excavator

has two forms: mechanical walking and hydraulic walking

the former is mainly at the level of 5 ~ 6 tons

in fact, w in Zhanyang, Guizhou is also like this. It has a large number in China, but now the sales volume is very small. However, if agricultural excavator enterprises in Shandong want to produce such products, there is a market

more and more manufacturers of the latter see the future of this market. The models are mainly 6T, 8t and 10t, and the prices are 120000 ~ 140000, 160000 ~ 180000 and 140000 ~ 230000. Almost every manufacturer of some sizes is preparing or has launched

4. Full swing crawler excavator

enterprises represented by Hengte heavy industry and Fulin, the main models are 6T, 8t and 12t, and the prices are about 180000 ~ 260000, 180000 ~ 200000 and 140000 ~ 230000

II. The main problems in the hydraulic system of agricultural excavators at present

1. Most of them use single pump and single circuit system, which can not achieve compound action. Although 65 glass magnesium plate is designed with 1 ~ 2 M valve cores, the effect is not ideal

2. Use large flow to make up for low pressure, and use large oil cylinders to meet the appropriate excavation force, resulting in the selection of too large engines, so the fuel consumption is large and the efficiency is low

3. The full swing excavator adopts the double pump and double circuit system, but it is still the quantitative pump system. The quantitative system determines the engine with larger requirements to meet the needs of load

III. development direction of hydraulic parts of agricultural excavators

Ruilong company has developed several hydraulic systems for agricultural engineering machinery to meet the needs of different customers

1. The wheel excavation with 180 ° deflection

adopts a double pump and double circuit system. As a quantitative system, it is recommended to use (25+25) ml/r double pumps. The dipper and crusher adopt the combined flow of double pumps in the valve, the combined flow outside the boom large chamber valve and the combined flow outside the bucket large chamber valve

2. Excavator loader

on the "1" system, hydraulic walking is selected to make up for the lack of walking driving force. When walking, the double pump can be designed to merge outside the valve to speed up the walking speed

on the basis of "1", add the travel circuit to the two circuits

3, 6T system

three pump system, variable system, (25 × 2+15.9+4.5) or (28*2+19.2+4.5), which can effectively reduce the power demand of the engine

the independent oil circuit of P3 pump is used for slewing and bulldozing, so as to better realize the composite operation with slewing when lifting the boom, and the confluence of boom and stick increases the operation efficiency

for crawler excavators, the multi-channel valve with unique design ensures the straight travel of the excavator

4, 8t system and 10 ~ 13 ton system

adopt two pump system. When the chain segment is heated to have sufficient activity capacity, the system displacement is 55*2, 64*2, 71*2 or 80*2ml/r, effectively reducing the power demand of the engine. The rotary reducer with heavy bearings can be selected with or without mechanical brakes. The unique two-way buffer valve design, coupled with the matching of multi-channel valve spool, makes the rotary operation more comfortable and reliable

IV. several problems that need to be considered for agricultural excavators

agricultural excavators do not mean that they are shoddy, that they can produce products with low quality and poor performance, but also need to consider the following problems

1. As with standard excavators, attention should be paid to the control of the cleanliness of the hydraulic system, mainly in:

a) welding and cleaning of steel pipes and hydraulic oil tanks

b) the hydraulic oil return circuit is equipped with oil return filtration, and the hydraulic oil suction circuit is equipped with oil suction filtration

2. Consider using variable system to effectively reduce engine power

3. Consider the matching of pilot valve and multi-channel valve, strengthen the improved design of multi-channel valve spool, and improve the operating performance of the machine

current product introduction of Ruilong company

in addition to developing hydraulic parts suitable for the above agricultural excavators, Ruilong company has also paid attention to the development of hydraulic parts of standard hydraulic excavators for one year, mainly including the development of five series of products of 1.3 ~ 1.5 ~ 1.8T, 3.5 ~ 4.5t, 5.5 ~ 6.0t, 7 ~ 8.5t and 10 ~ 13T. Parallel propulsion includes main pump and rotary. We should strengthen the development of motor assembly, travel motor assembly, multi-channel valve and pilot valve. The following products have been verified by our own installation:

1, 1.3 ~ 1.5 ~ 1.8T

A) multi-channel valve

our multi-channel valve is a chip multi-channel valve, which can be designed according to the requirements of users to meet different needs. The price is only about 70% of the imported parts

b) slewing motor assembly

according to years of work experience, the slewing reducer we designed has strengthened the bearings and seals. In order to reduce the overall size, we designed a special cycloidal motor and slewing buffer valve, which can meet the needs of customers

2, 3.5 ~ 4.5t, 5.5 ~ 6.0t, 7 ~ 8.5t, 10 ~ 13T main valves

according to a variety of main valves in the current market, according to the years of professional experience of Ruilong application engineers, the multi-way valve with its own intellectual property rights is designed, which is more suitable for the needs of the domestic market. The price is only 50 ~ 70% of the import price

3. Pilot valve

referring to a variety of pilot valves at home and abroad, we have designed our own special sealing ring, which fundamentally solves the problem of ensuring that the low pressure does not leak when the machine is stopped

4. Pilot oil source block

pressure reducing valve, overflow valve, one-way or two-way or three-way electromagnet, accumulator and high-pressure filter can be designed together according to user requirements

let's care about and support the healthy development of domestic agricultural engineering machinery, and let's pay attention to and support the development of domestic hydraulic parts manufacturers