Why use dual-fuel forklifts?
Application of liquefied gas forklifts Development of liquefied gas forklifts In the late 1960s and early 1970s, due to the shortage of international crude oil supply, major Western industrial countries had to find new energy sources to replace crude oil. Cleaner and more economical liquefied gas was studied and developed at this time, becoming a new generation of vehicle fuel to replace gasoline and diesel. At the same time, forklifts using liquefied gas as fuel also developed accordingly. Developed countries and regions such as Europe and the United States have vigorously promoted the use of liquefied gas forklifts to meet the needs of carbon emissions, occupational health and efficient operation of enterprises. In recent years, liquefied gas forklifts have continued to expand their market share in developed countries such as Europe and the United States, and their sales have greatly surpassed diesel forklifts and electric forklifts.
Since the reform and opening up, with the vigorous development of China's processing and manufacturing industries, especially in the Pearl River Delta and the Yangtze River Delta, forklifts have fully played their role in handling goods in all walks of life. Foreign-funded and Sino-foreign joint ventures that set up factories in mainland China still retain the habit of using liquefied gas forklifts abroad, which has driven the sales of domestic liquefied gas forklifts. The Chinese government has also begun to pay attention to energy conservation and emission reduction of motor vehicles. The China Industrial Vehicle Association has set energy conservation and environmental protection as the development goal of the "12th Five-Year Plan". Economical, environmentally friendly and efficient liquefied gas forklifts are favored by more and more companies. Why is liquefied gas forklift the future development trend of the forklift industry? What are its advantages? Compared with diesel forklifts
--Liquefied gas beats diesel with an absolute advantage in fuel cost.
--Liquefied gas forklifts are suitable for working indoors and outdoors, and even in working environments with particularly high environmental protection requirements.
--Unlike diesel, liquefied gas does not spill pollutants during the vaporization process, effectively extending the life of the engine.
--Liquid gas forklifts emit almost no harmful particles during operation, thus ensuring the health of workshop workers. The emission of a large number of harmful particles in the exhaust gas of diesel forklifts seriously affects the health of workers' respiratory system.
--The engine vibration amplitude of liquefied gas forklifts is small and the noise is low, which ensures the hearing of workers.
Compared with electric forklifts
--Due to the high industrial electricity price and battery purchase price, the maintenance cost of electric forklifts is high, and liquefied gas forklifts can save more use costs than electric forklifts.
--Even in the case of insufficient fuel, liquefied gas forklifts can always maintain power. The power of electric forklifts will decrease as the power decreases.
--Liquefied gas forklifts can travel on uneven surfaces or steep slopes.
--The carbon emissions of liquefied gas forklifts throughout the product life cycle, i.e. the "carbon footprint", are much smaller than those of electric vehicles.
--Liquefied gas forklifts are quick and convenient to change fuel, while electric forklifts require 8 hours of charging time and 8 hours of battery cooling time.
--Battery manufacturers of electric forklifts seriously affect the local ecological environment and human health. There have been many "blood lead" incidents in China caused by illegal discharge of pollutants by battery companies.
--Liquefied gas forklifts can work at a low temperature of minus 20 degrees.
Natural gas forklift
In the process of using liquefied gas forklift, in order to use it reasonably, the following points should be achieved: 1. First, be familiar with the relevant manuals of liquefied gas forklifts, and have a comprehensive understanding of the liquefied gas conversion system. During the use of the forklift, the forklift should not be parked near heat or fire sources, such as open flames, burning cigarette butts, sparks, electric welding, machines that can generate high temperatures, and electrical equipment: Do not adjust or modify the liquefied gas conversion device without authorization; Regular maintenance and inspection should be carried out on schedule; Stay alert and deal with any leakage or abnormal phenomenon immediately. 2. Achieve reasonable start-up: If dual-fuel uses liquefied gas, you should confirm whether the manual valve on the cylinder is fully opened before work. When the forklift is idle for a long time, its manual valve should be closed: There is no need to step on the accelerator when starting. The dual-fuel system must rotate the switch to the liquefied gas position. After starting, especially in cold areas, it is best to warm up the car for two or three minutes to allow the cooling water system of the internal combustion engine to heat up before driving to ensure that warm water can flow into the vaporizer to accelerate vaporization.
3. Pay attention to the fuel switching method (single-fuel forklifts do not need to be considered): For dual-fuel vehicles, the switching should be done when the forklift is stopped and cannot be switched while driving; when switching from gasoline to liquefied gas, let the internal combustion engine continue to run at the total speed. At this time, the switch can be turned to the middle position to let the gasoline stored in the carburetor burn out until it is turned off, and then the fuel switch can be turned to the liquefied gas position to restart; when switching from carburetor to gasoline, the switch can be directly turned to the gasoline position without stopping in the middle position. At this time, pay attention to pull out the cable. When the dual-fuel system is mainly burning liquefied gas, it is necessary to keep at least 1/4 of the fuel in the gasoline tank in case of emergency. And occasionally you need to burn gasoline to ensure that the gasoline system does not malfunction due to long-term idleness and to prevent the oil pipeline from embrittlement. It is recommended to burn 10 kilograms of gasoline every month.
4. Do the right gas filling; there are two ways to fill gas, one is to change the bottle: the other is to fill directly in the car. When filling or changing the bottle, it must be outdoors to ensure good ventilation. Safety should meet the requirements of local fire protection standards. The car must be parked and turned off, and the driver must leave the driver's seat. Fireworks, heat sources, and fire sources are strictly prohibited around. Handle the cylinder carefully, and do not collide, throw, or roll on the ground. The gas filling personnel must monitor the whole process of filling and must not leave the scene. When filling, put the gas gun on the filling valve on the bottle and tighten it. At the same time, unscrew the 80% liquid level hole on the bottle and start filling. When white mist comes out of the 80% liquid level hole, stop filling immediately, tighten and close the 80% liquid level hole, and check whether the liquid level gauge indicates the correct amount.
Differences between electric forklifts and liquefied gas forklifts
Liquefied gas engines are internal combustion engines. After burning fuel, they push the piston in the cylinder to make a reciprocating motion to convert the chemical energy in the fuel into mechanical energy to drive the vehicle forward. Battery forklifts convert chemical energy into mechanical energy. The main difference between liquefied gas and batteries is the difference in ignition methods caused by the physical properties of the fuel, which shows their different thermal
efficiency, economy, etc. A simple comparison is as follows:
Battery forklift
Features: The battery pack itself is heavy; the motor has poor acceleration and starting performance. The whole vehicle is restricted by the design of the battery pack and is not suitable for working in places with poor road conditions. Standard 8-hour daily fuel consumption: Assuming an 80V520AH battery pack, a three-phase charger input power of 8.9KVA, and a charging time of about 10 hours, it is estimated that each full charge will consume 100 degrees of electricity, which is 125 yuan based on the price of 1.25 yuan/kilowatt on March 10, 2009. Sustainable working time: According to the ampere-hour of the battery pack, it generally takes 10 hours to charge for 8 hours of work, which means that it can only work one shift a day. Later purchase cost: The battery pack needs to be replaced every 3 years, and the cost is roughly 28,000 yuan. Based on the international standard of 1,000 charge and discharge, the additional cost per day is roughly 35 yuan, and the depreciation cost of the smart charger needs to be increased by 12 yuan per day.
Comparison of costs for 250 days of annual work: 3-ton battery forklift, 80V520AH battery pack, charging time is about 10 hours, and 250 days of work: 250 days * 125 yuan/day = 31,250 yuan
2. Liquefied gas forklift
Features: small size, light weight, good starting performance, low price, high speed at maximum power; low vibration and noise.
Standard 8-hour single-day fuel volume: According to the calorific value, it is equivalent to 5.15 liters per hour. Based on the price of 2.61 yuan/liter = 4.93 yuan/kg on March 10, 2009, it is 41 liters per day for 8 hours, about
107 yuan.
Sustainable working time: Replacing the liquefied gas cylinder can continue to work.
Later purchase cost: The gas system is generally attached to the engine. Users only need to purchase a certain number of liquefied gas vehicle cylinders according to production conditions. The market price of each cylinder ranges from 150 to 200 yuan.
-Comparison of costs for 250 days of work per year: K25 engine works 250 days on a 3-ton forklift: 250 days * 107 yuan/day = 26,750 yuan.
Comparison of advantages and disadvantages:
1. Due to the short working time and long charging time of electric vehicles, they are generally not competent for multi-shift work (of course, 2 to 4 battery packs can be considered to solve the problem): battery vehicles can only be used on roads with good working conditions; acceleration and starting performance are significantly worse than internal combustion engines; the most critical thing is that in order to avoid battery explosion, the customer's site also needs a charging and discharging site with a good environment, and regular water replenishment is required, otherwise the battery life is greatly reduced. Compared with the limitations of its use, the comprehensive cost performance is not higher than that of liquefied gas (liquefied petroleum gas) vehicles in some occasions. However, if the user does not consider the time efficiency of charging and the user's on-site working conditions are very good, then the electric forklift is the first choice.
2. Liquefied gas forklift:
(1) Good emissions. Even the simplest open-loop system greatly reduces exhaust emissions. Compared with gasoline, the use of propane reduces CO emissions by 80%, HC by 75%, and NOx by a significant decrease, which plays a positive role in environmental protection.
(2) It is conducive to improving the lubrication condition of the engine. When using liquefied gas as fuel, since the mixed gas entering the engine is a dry mixed gas, the poor gasoline atomization that occurs when using gasoline will not occur. In addition, since there is very little carbon deposit during combustion, the good lubrication condition can extend the service life of the engine by more than double, and also extend the service life of the engine oil, reducing the maintenance cost of the engine.
(3) Improve the working condition of the engine. Since the main component of propane is propane, it has excellent anti-knock performance, an octane number of more than 120, and is not prone to knocking. It can significantly reduce the noise of the engine. At the same time, since the combustion is complete and there is no carbon deposition, the overhaul time of the engine is greatly extended, which can save 50-80% of the maintenance funds.
(4) Reduce fuel costs. Based on today's oil prices, it can save about 1/2 of the daily diesel cost. With the country's fuel tax policy increasing year by year, the economic benefits are very obvious.
(5) It has reliable safety. Since the ignition point of vapor is higher than that of gasoline, the latent heat of vaporization is large, and it has a self-cooling effect, its safety is greatly increased. The cylinder has undergone physical tests, water pressure tests, explosion tests, impact tests, drop tests, fire tests, gunshot tests, penetration tests, and operation tests, and is equipped with explosion-proof devices to ensure safety. (6) For dual-fuel forklifts, since there are two backup fuels, the working time of this type of forklift is increased by about one time. It is beneficial to the multi-shift work system of customers.