Equipment lubrication management

Thread Content

2. Types of Lubricants and Their Performance Parameters 　　 Due to the special nature of pharmaceutical production, pharmaceutical equipment needs to be properly lubricated in order to remain operational. At the same time, it is necessary to ensure production quality by preventing any potential secondary contamination of the equipment, as well as avoiding all factors that could pose a threat to the safety of drugs. Therefore, GMP considers the structure, performance, parameters of pharmaceutical equipment, as well as the lubricants used with it, to be sources of contamination, and these aspects are regarded as key points for controlling and verifying the performance of equipment in pharmaceutical production. Therefore, mastering the basic knowledge of lubricants is key to selecting them properly, ensuring proper lubrication of equipment, and maintaining the quality of pharmaceuticals. 　　 2.1 Types of Lubricants 　　 2.1.1 Liquid Lubricants 　　 Liquid lubricants mainly include mineral oils, animal and vegetable oils, synthetic oils, and water. These lubricants can form an oil film between the frictioning surfaces, completely separating the two surfaces from each other; the friction occurs between the liquid molecules within this oil film, thereby achieving the purpose of lubrication. 　　 2.1.2 Semi-solid lubricants Semi-solid lubricants mainly include animal fats, mineral oils, and synthetic fats. These types of lubricants can form a semi-solid adsorption film between the friction surfaces, thereby achieving the purpose of lubrication. 　　 2.1.3 Solid Lubricants Solid lubricants refer to solid substances in powder or film form that are added between the moving surfaces in contact with each other, thereby creating an embedded solid abrasive layer to achieve the purpose of lubrication. It is mainly used in friction areas where the use of lubricants is not possible or inconvenient. Common materials include graphite, molybdenum disulfide, polytetrafluoroethylene, nylon, lead, etc. 　　 2.1.4 Gas lubricants Gas lubricants mainly include gases such as air, nitrogen, and helium. Their main advantages are low viscosity, minimal variation in viscosity with temperature, extremely low frictional resistance, low temperature rise, and low raw material costs; they are particularly suitable for lubricating precision equipment and high-speed bearings. 　　 Among them, liquid lubricants (lubricating oils) and semi-solid lubricants (greases) are the most commonly used lubricants in pharmaceutical equipment. 　　 2.2 Performance indicators of lubricants The most commonly used lubricants in pharmaceutical equipment are lubricating oils and greases; their performance is analyzed as follows: 2.2.1 Main performance indicators of lubricating oils (1) Viscosity, which indicates the thickness of the lubricating oil. It represents the internal friction force that arises when there is relative movement between the oil molecules. The magnitude of this resistance is expressed by viscosity; the higher the viscosity, the greater the internal frictional resistance and the poorer the fluidity. Viscosity is the most important performance parameter of lubricating oils, and it is also the main factor considered when selecting such oils. (2) Flash point refers to the lowest temperature at which, under certain conditions of heating, the vaporized oil mixture with air reaches a certain concentration that allows it to ignite in contact with a flame, resulting in a brief flash fire. The lowest temperature at which the flickering persists for more than 5 seconds is called the ignition point, which serves as a measure of the flammability of lubricating oils. For lubrication in high-temperature and flammable environments, lubricants with a flash point 20–30°C higher than the operating temperature should be used. 　　 (3) The freezing point refers to the highest temperature at which the lubricant loses its ability to flow freely under specified conditions. It not only indicates the wax content in the lubricant but also serves as an important indicator for the performance of the lubricant at low temperatures. The operating temperature of ordinary lubricants must be 5–10°C higher than their freezing point. 　　 (4) Others: Other performance indicators of lubricating oils include the acid number, which reflects corrosion resistance ； Antioxidant stability reflecting the ability to resist oxidative deterioration ； Reflects the anti-emulsification property when mixed with water ； Corrosivity, which reflects the degree to which lubricant causes corrosion in metals, etc. Many of its properties need to be improved using additives, such as antioxidant preservatives, anti-emulsifiers, antifoamers, demulsifiers, thickeners, etc. In actual production, under many operating conditions, the use of additives can **improve** the performance of lubricants, and their service life can also be extended significantly. 　　 2.2.2 Main performance indicators of grease 　　 (1) Appearance, including color, luster, transparency, consistency, impurities, and uniformity. Generally, a thin layer of 1–2 mm of lubricant is applied to clean, colorless glass, and then inspected under light. 　　 (2) Penetration, an indicator that characterizes the consistency of grease, indicating the level of internal resistance and the degree of fluidity in the grease. The lower the penetration, the harder the grease, the greater its viscosity, the stronger its load-bearing capacity, and the better its sealing performance ； Conversely, the greater the liquidity, the weaker the load-bearing capacity, and the sealing performance is also relatively poorer. The selection should be based on temperature, speed, load, and operating conditions. 　　 (3) Dropping point, indicating the heat resistance of the grease. The drip point of grease determines its operating temperature; when using it, it is necessary to choose grease with a drip point that is 20–30°C higher than the operating temperature. 　　 (4) Others: Other performance indicators of grease include: resistance to air oxidation, i.e., oxidative stability ； Mechanical stability, the ability to resist mechanical shear forces ； The stability of colloids, which enables them to resist the effects of temperature and pressure while maintaining their colloidal structure. In actual production, under many operating conditions, the use of additives can **improve** the performance of lubricants, allowing their service life to be extended significantly. 　　 3. Selection of lubricants 　　 Only by using lubricants correctly can their technical properties be utilized, which in turn ensures the proper operation of pharmaceutical equipment, prolongs its lifespan, saves on lubricant costs and energy consumption, and enhances economic and social benefits. 　　 3.1 Basic requirements for selecting lubricants 　　 In the lubrication management of pharmaceutical equipment, in addition to meeting the prerequisite that the selected lubricant must not cause secondary contamination of drugs or affect their quality, it must also satisfy the following requirements: it should have an appropriate viscosity, be able to form a lubricating film between the moving parts of the friction pairs, and not easily leak away ； It has sufficient oiliness, allowing it to adhere firmly to the friction surfaces and form a strong, pressure-resistant flexible film that can withstand certain loads without being crushed ； It has a certain degree of stability, which prevents it from oxidizing and deteriorating, thereby preserving its effectiveness. 　　 3.2 Criteria for selecting lubricants 　　 3.2.1 Original data on pharmaceutical equipment 　　 It is advisable to use the lubricants specified or recommended in the manufacturer’s instructions for the pharmaceutical equipment, as the products and designs involved have undergone thorough evaluation and extensive testing regarding the lubricants to be used in such equipment; generally, the lubricants they recommend are highly reliable. 　　 3.2.2 Load conditions 　　 When the load is high, it is necessary to choose lubricating oil with a higher viscosity or lubricating grease with a lower penetration. Various lubricants and greases have a certain load-carrying capacity. Generally, oils with higher viscosity result in oil films that are less likely to be disrupted in friction pairs; for low-speed, high-load friction pairs operating in a boundary-lubrication condition, the adhesiveness and extreme pressure properties of the lubricant also need to be taken into account. 　　 3.2.3 Relative motion speed 　　 For high-speed, low-load moving pairs, lubricants with lower viscosity or greases with higher penetration should be used ； For high-speed rotating joints, the effect of centrifugal force must be taken into account; lubricants with higher viscosity or greases with lower penetration should be selected as long as the temperature rise remains within acceptable limits ； Reciprocating and intermittent motions experience large speed variations, which are unfavorable for the formation of an oil film; therefore, lubricants with higher viscosity should be used. 　　 3.2.4 Surface roughness 　　 For moving pairs that require high surface precision and small clearances, lubricants with lower viscosity should be used. In particular, the bearing clearance of the spindles in precision components is the main factor that determines the viscosity of the lubricant to be used. For kinematic pairs with a rough surface, lubricants with higher viscosity or greases with lower penetration should be used. When the hardness of the materials of the components in contact is low, a lubricant with higher viscosity should also be selected. 　　 3.2.5 Operating Temperature and Environment 　　 When the operating temperature is high, lubricants with a high flash point, high viscosity, and good oxidation stability, or greases with a low penetration value, high drip point, and high heat resistance, should be selected ； At low operating temperatures, lubricants with a lower freezing point, lower viscosity, and less moisture, or greases with a higher penetration value and low-temperature resistance, should be selected ； In working environments with corrosive media, lubricants with good corrosion and rust resistance should be selected ； In humid working environments, or under conditions where there is frequent contact with water, lubricants or greases with strong emulsion resistance, as well as good oiliness and rust-resistant properties, should be selected. 　　 3.2.6 Lubrication system 　　 For wear-prone components such as oil nozzles, oil cups, and oil holes that require manual lubrication, lubricants with an appropriate viscosity should be used ； For lubrication areas that absorb oil through oil lines and oil felt, lubricants with lower viscosity should be used ； For circulating lubrication systems, the lubricating oil is also required to have high antioxidant stability and minimal mechanical impurities, in order to ensure the long-term cleanliness and stability of the system. 　　 Based on the various criteria for selecting lubricants mentioned above, in practical applications it is necessary to make a reasonable decision by taking into account the operating conditions of the equipment, the requirements set by the manufacturer, as well as the specifications and descriptions related to the oil. The goal is to meet the technical requirements for lubrication while also ensuring cost-effectiveness. 　　 4 Methods for Lubrication Management of Pharmaceutical Equipment 　Lubrication management of pharmaceutical equipment is highly complex and cumbersome; it should be managed based on the actual conditions of the equipment during the production process. Pharmaceutical companies should pay attention to lubrication management and can take the following measures to improve its level. 　　 4.1 Formulating a lubrication management system 　　 Establish the policies and objectives for the company’s lubrication management; determine the organizational structure for such management based on the size of the pharmaceutical company, the characteristics of its equipment, production conditions, and manufacturing processes, and develop relevant rules and regulations. The lubrication management system clearly specifies the responsibilities for lubrication management assigned to the enterprise, production workshops, and operators, and establishes a lubrication management organization structure. Each pharmaceutical production workshop is equipped with a lubrication supervisor who is responsible for managing the lubrication of the equipment in that workshop, ensuring that proper attention is paid to this aspect of equipment maintenance. 　　 4.2 Strengthening education and training on lubrication knowledge Maintenance tasks such as performance monitoring of pharmaceutical equipment during operation are primarily carried out by operators, while the repair or adjustment of the equipment relies on the skills and sense of responsibility of maintenance personnel. Lubrication techniques and management are put into practice through the efforts of both operators and maintenance workers. Given the varying skill levels of employees in pharmaceutical companies, with most of them lacking basic knowledge of lubrication techniques and management practices, it is crucial to provide them with training in these areas. Companies should hold regular training sessions on equipment lubrication each year, and implement the \"five fixed principles\" of proper lubrication – fixing the quality, quantity, timing, location, and responsible person – to ensure that equipment is lubricated correctly, reasonably, and in a timely manner. 　　 4.3 Regular inspection of lubrication equipment 　　 Enterprises should regularly inspect and monitor the lubrication status of their equipment, in order to identify and resolve any issues within the lubrication system promptly. The inspection includes the lubrication equipment, the usage of lubricating oil, the condition of equipment lubrication, as well as records of oil filling and replacement. Any issues identified must be addressed and corrected. 　　 4.4 Improve equipment lubrication documentation 　Records should be kept for the lubrication of critical equipment; these records should include diagrams showing the lubrication system, the locations that require lubrication, and the names of the lubricants used. Detailed records of any repairs carried out on the lubrication equipment should also be maintained, to provide a basis for better maintenance of such equipment.