Detection and use of old construction machinery to delay the aging of equipment

As a brand-new approach to restoring the performance of old construction machinery, refurbishment gives the equipment a second life and effectively enhances the average working efficiency of the equipment during its service life. However, most of the construction machinery dealers and users in China do not have a clear concept of refurbishment. Many even think that "refurbishment" is just another interpretation of major overhaul. In fact, refurbishment is far from major overhauls. It has relatively strict standards in aspects such as equipment selection and factory inspection. More importantly, refurbishment to a certain extent is a comprehensive restoration of the equipment's factory performance. As second-hand equipment, it has higher quality and better performance. In today's era of energy shortage, renovation not only holds profound practical significance but also has a promising market development prospect.

Equipment refurbishment is different from major overhaul

It is understood that refurbishment refers to a process method in which only the basic components of the equipment are retained, all moving parts are updated, and finally the manufacturing standards are restored. It is at the highest level in the field of construction machinery maintenance.

According to experts, the maintenance of construction machinery during its service life can be divided into three levels. The highest level is refurbishment, which involves disassembling and reassembling the entire machine and falls within the category of remanufacturing. Every refurbished piece of equipment is renovated from the inside out, from mechanical to electronic, thus ensuring that the performance indicators of the equipment reach or even exceed the standards of brand-new equipment (original machine). Secondly, there is the generally referred to equipment maintenance, which is a means of restoring the main functions and normal working state of the equipment by replacing all damaged parts on the basis of inspecting the main components. The lowest level is simple maintenance of mechanical equipment, that is, to maintain and lubricate the equipment, etc., to ensure that the equipment is in good working condition.

Experts believe that the difference between refurbishment and major overhaul lies in that major overhaul of equipment mainly focuses on repair, while refurbishment mainly involves the replacement of moving parts and the new processing of basic parts, which are the concepts of "repair" and "replacement". Refurbishment involves the complete disassembly of the entire machine, and the re-inspection and new processing of each basic component in accordance with the original factory parts standards. This includes the processing of unqualified shaft holes, the detection and correction of cracks, etc., to restore all parts of the machinery to their original dimensions. Then, new moving parts are reassembled and inspected to meet or basically meet the original machine standards. In addition, technological upgrading is also a major feature of renovation, which can optimize equipment performance by improving the original control system and actuating components. For instance, Jinan Fuqiang Power Co., Ltd. of Sinotruk can refurbished and remanufacture Steyr engines that do not meet the Euro II standard to bring them up to the Euro II standard.

Maintenance is a technical measure taken during the usage stage of a product to maintain its good technical condition and normal operation, often featuring randomness, in-situ nature and emergency response. Maintenance and refurbishment follow different principles in the replacement of components. Major equipment overhauls focus more on correcting damaged parts. For instance, a pin shaft inside a certain part of the equipment was originally supposed to be a transition fit, but due to wear, it may have reached the range of clearance fit. At this point, refurbishment solves the problem by replacing the component. Major overhauls, on the other hand, restore the original transition fit by installing gaskets and sleeves.

The refurbishment process begins with repurchasing second-hand equipment from users. Then, the refurbishment manufacturer needs to comprehensively collect and verify the previous usage data of the equipment, including usage time, working environment, maintenance records, etc. Secondly, all the equipment is disassembled to conduct flaw detection on each basic component. Then, a comprehensive new treatment is carried out on the engine, hydraulic system, electrical system, chassis and other working accessories of the equipment. Finally, new moving parts are added for assembly. After the entire machine passes the performance test, it is released for sale. At present, almost all enterprises engaged in equipment refurbishment have formulated a complete set of inspection standards for refurbished equipment in accordance with the factory standards for new machines, and provide a certain equipment warranty period accordingly.

However, experts point out that not every piece of equipment or at any stage of every piece of equipment is suitable for refurbishment. Equipment with low technical added value, short service life and low value is not suitable for refurbishment. Experts suggest that if the cost of equipment refurbishment exceeds 65% of the value of the new machine, then there is no value in refurbishing it. At present, the business of refurbishing complete machines is more concentrated on high-value and high-tech imported equipment such as large mining equipment, milling machines, pavers and hydraulic excavators.