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In addition to energy saving and consumption reduction, the current task of the cement grinding system is to improve the quality of the finished cement without reducing its production volume, so as to meet the ISO cement strength standards. Among the more than 8,000 cement enterprises in our country, only a small proportion can reach or come close to international standards; the vast majority of these enterprises have significant gaps compared to international standards in terms of cement fineness (specific surface area), early and late strength, particle size distribution, and particle roundness. This requires cement companies to innovate in the technology and equipment used for cement grinding in order to meet the ISO standards for cement strength. As is well known, the effective power of ball mills is about 1% to 2%, whereas that of crushers is 30% to 40%, representing a difference of roughly 15 to 30 times. Pre-grinding technology, which means “more crushing and less grinding,” is one of the excellent technical measures to be introduced into the cement grinding process. The PSL-type jet crusher plays an important role in pre-crushing technology. The PSL type jet crusher is characterized by the following features: First, it operates on the principle of \"centrifugal cleavage crushing\"; it has no hammers and few wear-prone components, which results in low maintenance costs and high operational efficiency. II. It has a compact structure, consisting of a main unit, an internal swirl device, an oil supply and lubrication system, an electrical control system, and a drive unit. The drive unit uses a V-belt to rotate the impeller of the main unit at high speed; surrounding the impeller is a crushing chamber formed by the machine body, within which three layers of impact plates are arranged in a specific pattern. III. After crushing, 80% of the material particles have a size of less than 5 millimeters; the particle size remains stable and is not affected by the degree of wear of vulnerable components. IV. An optimally designed distribution cone is installed at the center of the impeller to serve as a flow divider ； The channel structure is special, with material always forming a cushion to reduce impeller wear; meanwhile, the impellers are made of wear-resistant alloy materials, allowing each impeller to last for 2 to 3 years. V. The wear-prone nozzles are made of wear-resistant alloy materials; through optimized design, each protective plate is capable of processing 20,000 to 30,000 tons of clinker. VI. A counterplate with a unique structure is installed in the crushing chamber, and each counterplate can be adjusted upward, downward, or in terms of its orientation up to 6 times, **which increases the service life of the counterplates. VII. It is equipped with an oil supply and lubrication system as well as a bearing oil deficiency alarm device, which ensures continuous oil supply during the operation of the main engine to lubricate and cool the bearings. In the event of a lack of oil in the bearings, the alarm system emits a signal to shut down the machine, thereby ensuring the safe operation of the equipment. VIII. An internal swirl device is installed to circulate the high-speed air flow with a high dust concentration generated during the operation of the main unit, thereby reducing pollution to the external environment caused by dust leakage. 9. Compared with other crushers, this equipment is compact, requires less investment, yields quick results, operates stably, and has a high operational rate. When the PSL70 jet crusher was used in conjunction with a cement mill of 2.2×6.5 meters in diameter at a certain factory, the fineness of the cement remained unchanged, at 2%–4% on a 0.08 mm sieve (residue). The original production rate was 14–16 tons per shift, with an electricity consumption of 30–32 kWh per ton; now the production rate is 20 tons per hour, representing an increase of over 25% per shift, while the electricity consumption for cement production has decreased by about 15%. A raw material mill with a diameter of 2.2×6.5 meters in a circulating production system; the particle size of the material fed into the mill is 25 millimeters, with an average particle size of 15 millimeters. The raw material sieve residue is 8%, the output per shift is 25–28 tons, the power consumption for processing raw material is 19 kilowatt-hours per ton, and the installed capacity is 530 kilowatts. By using a PSL-type jet crusher and replacing the original double-rotor classifier with a KX-type high-fine rotor classifier, the residual solids in the raw material are reduced to 8%. The production rate is 35–36 tons per hour, with a maximum of 38 tons per hour. The electricity consumption per ton of raw material is 14.7 kilowatt-hours per ton, resulting in a reduction of 2.00 yuan in production costs per ton of raw material, for an annual savings of 500,000 yuan. (Note: Originally, the two raw material grinders supplied raw material for two kilns; now one grinder supplies raw material for two kilns, with a slight surplus remaining.) There are many devices used for crushing; jaw crushers, hammer crushers, impact crushers, and vertical shaft crushers, when used in combination with grinders, all yield certain results. However, the aforementioned crushers suffer from drawbacks such as leakage of large pieces, large variations in particle size, high maintenance difficulty, and high maintenance costs. The roller press developed in the late 1980s offers better control over particle size compared to earlier types of crushers, and its performance is also much improved; it is an excellent piece of equipment. However, the one-time investment in such equipment is high and maintenance is difficult; as a result, companies often cannot handle these issues on their own. The PSL type jet crusher can be used in conjunction with raw material mills and cement mills, and it is particularly suitable for cement mills. There are two ways to integrate it: one is to place it in front of the clinker storage area, where the clinker coming out of the kiln passes through an iron remover before entering the crusher, after which it is lifted into the storage area and mixed with other materials for grinding ； Another option is to place it in front of the feed end of the mill; the material, after passing through an iron remover and then into the crusher, enters the mill for grinding. Through practice, it has been found that in the use of PSL-type jet crushers, the best crushing efficiency is achieved when the particle size of the material is between 60 mm and 80 mm, with little powdered material present. Therefore, regardless of the method used, the best approach is to have the material pass through a vibrating screen or a rotary sieve before entering the machine, as this allows it to perform more effectively. When using this device, special attention should be paid to tasks such as iron removal, oil change, checking for wear, and maintaining cleanliness.