Prevention is better than Cure - Six Steps to Prevent Faults in Construction Machinery

The use of construction machinery often occurs in some harsh environments. Due to the influence of materials, processes, aging of parts and human factors, various faults are inevitable during the operation of construction machinery. If construction machinery malfunctions during the construction process, it will not only affect the normal construction progress and cause unnecessary financial losses, but also reduce the service life of the construction machinery. How to prevent malfunctions of construction machinery has become a frequently discussed issue among construction units. If the causes of various faults can be analyzed correctly and effective and targeted preventive measures are taken to slow down the damage rate of mechanical parts as much as possible, it is possible to effectively prevent further faults and extend the service life of machinery.

First, make every effort to minimize the influence of harmful factors

Reduce the impact of further impurities

Mechanical impurities generally refer to non-metallic substances such as dust and soil, as well as some metal shavings and wear products produced by the self-lifting of construction machinery during operation. Once these impurities enter the interior of the machinery and reach the mating surfaces of the machinery, the harm is very great. Not only do they impede the relative motion and accelerate the wear of parts, but they also scratch the mating surfaces, damage the lubricating oil film, and cause the temperature of the parts to rise and the lubricating oil to deteriorate. It has been determined that when the mechanical impurities in the lubricating oil increase to 0.15%, the wear degree of the first piston ring of the engine will be 2.5 times greater than the normal value. When impurity particles enter rolling bearings, their service life will be reduced by 80% to 90%. Therefore, for construction machinery operating in harsh and complex environments, it is necessary to use high-quality and well-matched components, lubricating oil and grease to block the source of harmful impurities. Second, it is necessary to do a good job in mechanical protection at the work site to ensure that the corresponding mechanisms can operate normally and prevent various impurities from entering the interior of the machinery. For malfunctioning machinery, it is advisable to have it repaired at a regular repair site as much as possible. When conducting on-site repairs, protective measures should also be taken to prevent the parts to be replaced from being contaminated by dust and other impurities before entering the machinery.

2. Reduce various corrosive effects

The phenomenon where the surface of a metal is damaged due to chemical or electrochemical reactions with the surrounding medium is called corrosion. This corrosive effect not only affects the normal operation of mechanical surface equipment, but also corrodes the internal components of the machinery. For instance, rainwater and chemical substances in the air can enter the interior of mechanical parts through their external channels, gaps, etc., corroding the interior of the mechanical parts, accelerating mechanical wear and increasing mechanical failures. Because this corrosive effect is sometimes invisible. What is intangible is easily overlooked by people, and thus its harmfulness is even greater. During operation, management and operation personnel should, based on the local weather conditions and air pollution situation at that time, take effective measures to minimize the impact of chemical corrosion on the machinery. The key is to prevent the invasion of rainwater and chemical components in the air into the machinery.

3. Reduce the influence of temperature

In work, each component has its own normal temperature range. For instance, the temperature of general cooling water is 80 to 90℃, and that of hydraulic oil in hydraulic transmission systems is 30 to 60℃. If the temperature is lower or higher than this range, it will accelerate the wear of parts, cause the deterioration of lubricating oil, and result in changes in material properties, etc. Tests show that the main transmission gears and bearings of various construction machinery wear out 10 to 12 times more when operating in lubricating oil at -5℃ than when operating in lubricating oil at 3℃. However, when the temperature is too high, it will accelerate the deterioration of the lubricating oil. For instance, when the oil temperature exceeds 55 to 60 degrees Celsius, for every 5 degrees Celsius increase in oil temperature, the oxidation rate of the oil will double. For this reason, during the operation of construction machinery, it is necessary to prevent overloading at low temperatures, ensure the normal operation during the low-speed preheating stage, and wait until the machinery reaches the specified temperature before driving or working. Do not neglect this important task just because no problems occur at that time. Second, it is necessary to prevent the machinery from operating at high temperatures. During the operation of the machinery, the values on various thermometers should be frequently checked. If any problems are found, the machine should be stopped immediately for inspection and any faults should be eliminated promptly. For cases where the cause cannot be identified for the time being, the machinery must not be allowed to operate while faulty without any treatment. In daily work, it is necessary to pay attention to checking the working condition of the cooling system. For water-cooled machinery, it is necessary to inspect and add cooling water before each day's operation. For air-cooled machinery, it is also necessary to regularly clean the dust on the air-cooling system to ensure the unobstructed flow of the heat dissipation air ducts.

Second, ensure reasonable lubrication of the machinery

Wear of the working surface of parts, corrosion of the part surface and aging of materials are the three main failure forms of mechanical parts under normal usage conditions, among which the failure caused by wear of the working surface of parts accounts for the largest proportion. That is to say, the wear and tear of machinery is one of the main reasons that push its various components to the limit technical state. Then, to solve the wear problem of mechanical parts, in addition to using high-quality materials, choosing advanced manufacturing processes and designing reasonable mechanical structures, an important task to be done during the usage process is to ensure the reasonable lubrication of the machinery. According to statistics, more than half of the malfunctions of construction machinery are caused by poor lubrication. Due to the precise fit of various components in construction machinery, good lubrication can help maintain normal working clearances and appropriate working temperatures, thereby reducing the wear of parts and minimizing mechanical failures. Normal and reasonable lubrication is one of the effective measures to reduce mechanical failures. To this end, first of all, it is necessary to select lubricants reasonably. Normal lubricant categories should be chosen based on the types and application structures of the machinery. Appropriate quality grades should be selected according to the requirements of the machinery. Suitable lubricant brands should be chosen based on the working environment of the machinery and different seasons. During use, neither low-grade lubricants nor other types of lubricants should be used as substitutes, and inferior products must not be employed. Second, it is necessary to frequently check the quantity and quality of the lubricant. If the quantity is insufficient, it should be replenished in time; if the quality is poor, it should be replaced promptly. Under emergency conditions, if different types and grades of lubricants are used as substitutes, the lubrication system must be cleaned afterwards and normal lubricants must be replaced in a timely manner.