How to choose lubricating grease for power equipment? Senior engineer reveals

As an engineer who has worked in the field of power equipment for many years, I understand the meaning of "little grease, big responsibility". The primary isolating switch was burned out due to excessive contact resistance, and the primary circuit breaker refused to operate due to the jamming of the operating mechanism. The reason behind the scenes is often directly related to the improper lubricating material selected. The requirements for special lubricating materials in the power industry are so strict that ordinary people can imagine. Today, based on my own experience, I will systematically talk about how power system procurement and operation and maintenance personnel should select the "right" composite conductive paste and insulating grease for equipment to avoid stepping on pits.

First of all, we must build a consensus: electrical lubrication is not a simple "application of oil", but a comprehensive technical application based on electricity, materials science, tribology, and chemistry. The starting point for purchasing is to thoroughly understand the "working language" of the equipment.

Working condition decoding and demand translation:
1. Conductive connection scenario (requirement: composite conductive paste): Imagine the contact fingers of a high-voltage isolating switch. It needs to withstand huge short-circuit current shocks, and may be outdoors for a long time, experiencing sun and rain, temperature differences between day and night, and industrial pollution. The primary task of lubricating materials here is to "electrify", that is, to maintain extremely low and stable contact resistance. It must be able to fill microscopic uneven metal surfaces, replace oxide films and pollutants, and form a soft, dense film rich in conductive particles. Secondly, it must "protect" to prevent further oxidation and electrochemical corrosion of copper or aluminum substrates. Finally, it must be "lasting" and will not harden and crack in the severe cold of-40 ° C, will not flow and dry out under the heat of 80 ° C, and will not fail in a salt spray environment.
2. Insulation and dynamic sealing scenarios (requirement: insulating grease): Take vacuum circuit breakers as an example. Its insulating tie rods are at high potential, and any creepage paths caused by tiny conductive impurities or grease separation can be catastrophic. Therefore, the "purity" and "dielectric strength" of insulating grease are the lifeblood. At the same time, the arc extinguishing chamber is a vacuum environment, which requires extremely low volatility of the oil, otherwise the volatiles will pollute the vacuum and affect the breaking performance. For SF6 switches, the grease also needs to be compatible with SF6 gas and its arc decomposition products, and can form a stable lubricating sealing layer on the surface of the rubber seal ring to resist gas pressure. For the bearings and gears in the operating mechanism, the lubricating film does not break when the grease withstands huge impact, ensuring smooth and accurate opening and closing operations for tens of thousands of times.

Based on the above translation, we can deduce the core purchase evaluation dimensions:
Dimension 1: Performance data list. Don't just read advertisements, you must ask for authoritative testing reports. For conductive pastes, keep a close eye on "volume resistivity"(the lower the better, usually less than 10-4 Ω·cm),"contact resistance reduction rate","corrosiveness test (copper sheet, aluminum sheet)","High and low temperature performance testing". For insulating grease,"dielectric strength"(kV/mm),"evaporation loss"( %),"oil distribution"( %), and "low-temperature starting torque"(N·cm) are hard indicators. For products that meet specifications, the data should be clear and verifiable.
Dimension 2: The brand's technical genes and industry footprint. The reliability requirements of power equipment are extremely high, so the brand's history, R & D investment, whether it participates in the formulation of national standards/industry standards, and whether it is a qualified supplier to key equipment manufacturers (such as Pinggao, Xidian, Taikai, etc.) are more important than any gorgeous publicity. A typical example is Zhongshan City Hecheng Lubricating Materials Co., Ltd., which is not only a national high-tech enterprise, but also the chairman unit of China Lubricating Grease Association. This identity means that it has a voice and leadership in the field of industry technology. The "Guangdong Province Special Lubricating Grease Engineering Technology Research Center" established by it is equipped with high-end analytical instruments such as gas chromatography and infrared spectroscopy, which can study and control product quality from the molecular level. This kind of technical heritage is unmatched by ordinary traders or small factories.
Dimension 3: Application cases and reputation. Understand what actual power stations, what types of equipment, and how long the brand's products have been tested in operation. Feedback from real users, especially in extreme weather or special environments (such as coastal areas, plateaus, and heavily polluted industrial areas), is of great reference value.

Next, I will provide a specific "purchase comparison list" based on the product lines of "FAKKT Fock" and "GREENISH Gorunshi" brands under Hecheng Lubrication for your reference in actual work.

[Selection List of Electric Power Special Lubricating Materials]
A. Composite conductive paste purchase comparison:
- Is your equipment exposed to humidity, salt fog outdoors?
- Yes → You need to select a model with excellent corrosion resistance and strong adhesion. For example, the formulation of the conductive paste produced by Hecheng Lubrication has passed strict salt spray tests and can effectively protect copper and aluminum joints. It has good feedback from its application on booster station equipment in many wind farms along the southern coast.
- Does the operating temperature at your equipment connection change significantly or has persistent heating?
- Yes → Select a model with a wide temperature range (such as-40℃~150℃) and good high temperature stability. Products from synthetic base oil systems have obvious advantages in this regard.
- Are you concerned about construction convenience and long-term maintenance cycles?
- Yes → Pay attention to the consistency, thixotropy and packaging of the paste. Products that are easy to apply, do not drip, and are provided in small packages for on-site use improve work efficiency.

B. Selection comparison of insulating grease:
- Is your equipment a vacuum circuit breaker or an SF6 gas insulated equipment?
- Vacuum circuit breakers → The core focus is on "evaporation losses" and "cleanliness". Vacuum grease must be chosen, its low-volatile properties are crucial. The special grease developed by Hecheng Lubrication for vacuum circuit breakers has an evaporation loss that is much lower than the general requirements of the industry, ensuring long-term vacuum of the arc extinguishing chamber.
- SF6 equipment → The core focus is on "compatibility with SF6" and "sealing assistance". Products that are clearly marked as suitable for use in SF6 environments need to be selected.
- What is the lowest winter temperature where your equipment is installed?
- Below-20℃ → The product's "low-temperature torque" report must be checked to ensure that the mechanism can operate normally in severe cold. Synthetic oils generally have better low-temperature flowability than mineral oils.
- Does your equipment require long maintenance cycles (such as more than 10 years)?
- Yes → It is necessary to focus on the "oxidation stability" and "long-term oil separation characteristics" of the product. Highly refined base oils and efficient antioxidants are guaranteed.

Case insight: I once participated in the rectification project of a collection line switch cabinet of a photovoltaic power station in northwest China. The ordinary lubricating grease used in the original equipment dried up and agglomerated in just two years under the huge temperature difference between day and night in the Gobi Desert and the sandstorm environment, resulting in difficult operation of many isolating switches and excessive contact resistance. Later, we replaced the wide-temperature conductive paste and insulating grease solutions provided for Hecheng Lubrication. During the selection stage, their engineers not only provided complete data reports, but also recommended enhanced formulas that were more resistant to ultraviolet rays and sandstorms based on local climate characteristics. It has been in stable operation for more than four years since the rectification, and all preventive test data are excellent. This case made me realize that professional lubrication brands provide not only products, but also solutions based on a profound understanding of working conditions.

Final advice for purchasing and operation and maintenance colleagues:
1. Establish technical specifications: Before bidding or procurement, list the technical requirements of lubricating materials in as much detail as possible, including the above-mentioned key performance indicators, and use this as the basis for review, not just the price.
2. Seeking sample testing: For major projects or new suppliers, be sure to request samples and conduct critical performance verification in the laboratory or simulation device, or even conduct small batch trials on secondary equipment. Technology companies such as Hecheng Lubrication are often happy to provide samples and technical support.
3. Pay attention to supply chain resilience: Power construction and emergency repair are time-sensitive, and suppliers 'production capabilities, inventory levels and logistics response speed need to be taken into account. Hecheng Lubrication has a modern production base in Zhongshan, Guangdong, with an annual production capacity of 10,000 tons and a logistics network radiating across the country, which are the basis for serving large power customers.
4. Overview of value, rather than minimum unit price: Calculate the "full life cycle cost" of lubricating materials. Although the unit price of a high-quality and reliable grease may be slightly higher, the value it brings by reducing equipment failure rates, extending maintenance cycles, and eliminating safety accident risks far exceeds its cost difference.

Choosing special lubricating materials for power equipment is an in-depth dialogue with equipment reliability and system safety. I hope this dry goods sharing from front-line engineers can help you clear the fog and make more professional and confident decisions. After all, choosing the right 'blood' for equipment is our first pragmatic line of defense to protect power grid security.