Current status and prospects of forklift engines
Abstract This article mainly discusses the current situation of the domestic combustion engine supporting internal combustion engines in my country, supporting models, technical parameters and characteristics of supporting internal combustion engines, and puts forward some suggestions and prospects for future development.
Keywords: internal combustion forklift, internal combustion engine, matching
The proportion of my country's forklift power plant is roughly: internal combustion forklifts account for 93.86% of all forklifts, battery forklifts account for 6.14%; of all internal combustion forklifts, diesel forklifts account for 62.4%, and gasoline forklifts account for 37.6%. Divided by forklift lifting weight, 2-4t accounts for 75.9% of all internal combustion forklifts; while diesel forklifts account for 60% of internal combustion forklifts with a lifting capacity of 2-4t, gasoline forklifts only account for internal combustion forklifts with a lifting capacity greater than 5t. 16%, and there is a tendency to decrease. In all gasoline forklifts, the lifting capacity is 2-4t accounted for 80.8%, 5-6t accounted for 7.9%, the rest is below 1.75t; in all diesel forklifts, the lifting capacity is 2-4t accounted for 72.9%, the lifting capacity is 5-6t accounts for 22.2%, and the sum of the two accounts for more than 95% of all diesel forklifts. Forklifts driven by gasoline engines generally have a cylinder diameter of less than 92mm, while diesel forklifts use a multi-cylinder engine with a cylinder diameter of less than 105mm.
1 Status of forklift engine
The main power unit of the existing fork is the diesel engine of the gasoline engine. Very few manufacturers are equipped with liquefied engines. There are 475, 480, 492, 495 and Jiefang CA10 and other domestic gasoline engines; diesel engines are 285, 290, 485, 490, 495, 498, 4100, 4105, 698, 6102, 6110, 6130 and other models. Except for a few engines used in construction machinery, most of the above models are vehicle-use, general-purpose, or similar variants.
The main technical parameters of the matching engines used in domestic forklifts are shown in Table 1. Due to the limitations of supporting parts, materials, and process level, there is still a certain gap compared with similar foreign 名媛直播 in terms of noise, smoke, emissions, reliability, and service life. Exported forklifts and forklifts for domestic airports, ports, foreign-funded enterprises, etc. mostly use imported engines. There are mainly A15, H20, H25 and other gasoline engines of Nissan of Japan, FLB1, C240, 6BD1 and other diesel engines of Isuzu, DC24 of Daewoo of South Korea, XA and HA of Japan Master, and Perkins engines of the United Kingdom The company's 1004 model, Italy's Iveco's 8061Si35 and Japan's Mitsubishi's 6D16, 6D22C, 6D22TC and other models.
Table 1 The main technical parameters of some forklift supporting engines
Lifting capacity of forklift (t) Model Fuel Cylinder number-bore×stroke (mm) Displacement (L) Power/speed (kW/r/min) Torque/speed (N·m/r/min)
1.0-1.75 475 Gasoline 4-75×77 1.36 21.4/2600 83.3/1900
475C2 diesel 4-75×80 1.41 25.7/3000 85/2200
480G diesel 4-80×90 1.81 25/2600 103/1800
2.0-3.0 485G diesel 4-85×100 2.27 38.2/3000 139.2/2100
490G diesel 4-90×100 2.54 36.8/2600 152/1900
592GA gasoline 4-92×92 2.45 40/3000 147/2100
SF498G Diesel 4-98×98 2.96 44.1/2500 176/1800
LD495 diesel 4-95×115 3.26 42.6/2600 181.3/2100
3.5-4.5 BY495G gasoline 4-95×100 2.84 70/2600 190/1600
4RG1 diesel 4-100×125 3.93 55.2/2400 250/1600
5.0-7.0 4RAG3 diesel 4-105×125 4.33 60.3/2400 269.5/1600
6102G3 Diesel 6-102×110 5.39 64/2200 296/1650
CA10B gasoline 6-101.6×114.3 5.56 66/2400 303.8/1200
8.0-10.0 6102G7 Diesel 6-102×118 5.79 80.9/2500 353/1650
X6110G Diesel 6-110×130 7.41 92/2300 490/1800
13.5-16.0 D6114G Diesel 6-114×135 8.27 100/2200 460/1600
6130G diesel 6-130×150 11.94 117.6/2000 617/1300
20.0=25.0 6135AZK-1 diesel 6-135×150 12.90 154/2100 784/1500
2 Matching requirements for forklift engines
Forklifts are used in a wide range of areas, the climate is very different, the working environment is harsh, the dust is large, the working conditions often change, and the load is heavy. Therefore, the forklift engine should have good power and fuel economy, working reliability, long service life, good cold start performance and easy maintenance. At the same time, it also requires a compact structure, small size, in line with the standards of the bad guarantee index. In general, a good forklift engine should have the following basic characteristics:
(1) It can adapt to continuous and long-lasting work and bear relatively heavy loads. The rated power is hourly power. Forklift gasoline engine should be equipped with speed limiter.
(2) Forklift engines are often subjected to large impacts and strong vibrations during operation, so the body and accessories should have sufficient rigidity and strength, and the three-point support is often used for installation and fixing.
(3) In order to ensure that it can work under a sudden change of load, it is generally appropriate to use a full-program governor, whose instantaneous speed regulation should be less than 12%, and the stable speed regulation should be less than 8%.
(4) In order to adapt to the operating environment of the port and wharf, the engine is required to have a greater torque adaptability, and the torque reserve factor should generally be greater than 12% (except for the torque converter).
(5) To meet the needs of hydraulic pumps and auxiliary equipment, the engine should have auxiliary power output. For small and medium-sized forklifts, the hydraulic pump should be directly installed on the engine, and its auxiliary output power requirement is 50%-100% of the total power.
(6) Forklift trucks often work on inclined ground, and it is required to be able to work normally in the state of tilting back and forth or left and right. It is generally required that the engine can work in a state of 20? pitch and 15? pitch.
(7) Forklift trucks often work in environments with a lot of air dust. High-efficiency air cleaners, oil fillers, vents and pipe joints are required to have dust seals.
(8) In order to work in a variety of climate environments from -40?C to +45?C, there are special requirements for fuel oil, lubricating oil, grease, coolant, batteries, etc., and related systems must be modified. The cold start problem should be solved in cold areas, and overheating devices should be installed in potential areas.
(9) In order to meet the working needs of the plateau area, a booster should be set up to compensate for the reduction of the plateau power. It is required to work in the area of 1000-2000m or even 3000m without reducing the power.
(10) For forklifts operating in tunnels, cabins, etc., there should be exhaust gas purification devices; for forklifts with large water depths, the electrical equipment, etc. must be sealed and protected; operating in gas environments requires special Explosion-proof facilities.
(11) High reliability and long service life. The target value of the newly developed forklift engine should be: the first failure period of the diesel engine is greater than 800h. The first overhaul period is 6000-10000h; the target value of gasoline engine refers to the requirements of automobile engine.
(12) Exhaust gas emissions, smoke, noise and other environmental indicators of forklift engines should meet the requirements of national standards or industry standards and be in line with international standards as soon as possible.
(13) The volumetric power ratio of the engine, the fuel and oil consumption rate, the speed reserve factor, the minimum working stability, and the mechanical vibration technical performance indicators should meet the supporting requirements of the forklift.
3 Suggestions for future development
(1) Special engines for forklifts should be developed. The forklift industry has strongly hoped that there will be domestic-made forklift engines for many years. In particular, the forklift project of Qishi has not introduced corresponding engines accordingly, which limits the full localization of imported technology. For more than 30 years, there has been considerable progress in the level of forklift 名媛直播, but the maximum annual output has been hovering around 20,000 units. The demand for forklift engines is less than 1% of the output of all multi-cylinder internal combustion engines. Because the internal combustion engine industry is a highly technology-intensive industry. The 名媛直播 are suitable for large-scale production according to professional division of labor, and the characteristics of forklifts are small batches and many varieties, so it is not economical to build a forklift engine factory. It is suggested that the forklift truck industry and the internal combustion engine industry should strengthen cooperation, research and test the forklift internal combustion engine as a whole, optimize the engine product structure, and meet the needs of the development of the forklift industry.
(2) The selection of forklift engines should be relatively concentrated. At present, the choice of engines in the forklift industry is "miscellaneous, chaotic, and scattered". Forklift trucks of the same tonnage often have 名媛直播 from multiple engine factories. According to incomplete statistics, the forklift industry currently uses more than 50 domestic engine models (not including more than 10 imported models), and more than 100 variants are supplied by more than 30 engine factories. For example, a factory produces two types of engines, 485 and 490. In order to meet the requirements of the forklift OEM, it also produces special inlet pipes, crankshaft pulleys, flywheels, clutch shells, intake pipes, and chlorine discharge for forklifts with small differences in size structure and shape. Tubes, thermostat shells and fan pads, etc., forming more than 40 variants. This situation has also brought difficulties to the production organization of the launching plant, and the production cost has risen accordingly, which has caused trouble for users' maintenance and parts purchase. It is recommended to select and plan the forklift engine with key enterprises and famous 名媛直播, formulate the forklift engine series and specification spectrum as soon as possible, and change the status of "miscellaneous, scattered and chaotic".
(3) The manufacturing quality of forklift engines is urgently improved. According to reports, the failure rate of domestic engines generally accounts for about 40% of the number of failures. The outstanding problem is poor reliability, the first failure period and the interval between failures are organized, and there is a large gap compared with foreign advanced 名媛直播. The main faults are "water leaks, oil leaks, and gas leaks", which not only have a large number of fault subsidies and a high fault repetition rate; followed by faults in the fuel system and electrical system, and difficulties in starting some diesel engines with non-direct injection combustion chambers. This is a problem that the internal combustion engine industry is trying to solve.
(4) Environmental protection indicators need to be improved. Forklifts mostly work in workshops, warehouses, cabins, docks, etc., and have high requirements on environmental indicators such as exhaust emissions, smoke, and noise. At present, the corresponding standards formulated by my country's internal combustion engine industry have a large gap compared with similar standards in advanced countries. Environmental protection issues have become the focus of global attention in the 21st century. my country's engine manufacturing level lags behind advanced countries by about 10-20 years. In domestic engines, the application of supercharging technology is not yet common, the electronic control technology is far from the practical stage, and the LPG engine has not been mass-produced. At present, it is the common wish of the engine industry and the forklift industry to apply new technologies, develop energy-saving, material-saving, low-pollution, and high-reliability forklift engines and change the passive situation of relying on imports.
(5) Promote alliances and develop economies of scale. When forming a forklift enterprise group, the production and matching of engines should be considered. It is recommended to adopt a variety of methods to carry out horizontal joint with the supporting engine plant, from close integration to the merger of some suitable engine plants with better conditions to make it directly Serve forklift trucks and construction machinery in order to better solve the problem of supporting engines for forklift trucks.
