In the metal processing and manufacturing industry, workpieces often need to go through a long or short storage cycle from production to final assembly or export. Some workpieces only need to be placed in the warehouse for a few days, while others have to be shipped overseas, or even stored in extreme temperature, humidity and salt spray environments for months or even years. The different protection cycles determine that the anti-rust plan must be changed accordingly. However, when many companies choose anti-rust products, they often fall into the misunderstanding of "a bottle of anti-rust oil makes the world": using long-term storage oil for short-term protection is expensive and subsequent cleaning is difficult; or using ordinary short-term oil for long-term storage, resulting in a large increase in the risk of rust. The Hank BS-400 series is a series of anti-rust products designed to solve this contradiction, which allows every need "from short-term protection to storage" to find a precisely matched solution.
The so-called "short-term anti-rust" is short for short-term anti-rust. It usually refers to the anti-rust treatment with a protection period of less than a few days to three months, which is suitable for turnover between processes, local transportation or temporary storage. The core requirements of short-term anti-rust are easy construction, fast drying, easy to be removed by subsequent processes, and the unit cost should be low enough. Many workpieces working in progress in mechanical processing plants often need to stay in the workshop for several days after machining, waiting for the next process; or sorting and transshipment before assembly. These scenes require a layer of light and dry anti-rust protection, which can not only isolate hand sweat and moisture in the air, but also do not affect subsequent operations. "Sealing" refers to long-term anti-rust packaging with a protection period of more than three months, or even as long as one or two years. Sealing and anti-rust requires stronger resistance to moisture and heat, salt spray and acid and alkali resistance, thicker oil film, better adhesion, and smooth cleaning or direct use when finally unsealed.
However, in the long-term market practice, the line between short-term prevention and storage is often blurred. Some factories use a valuable high-performance storage oil to save trouble. As a result, the surface of the short-term prevention workpiece is sticky, and after dust accumulation, it becomes a new source of rust. Moreover, the workpiece must be cleaned with solvent before going online, adding additional processes and costs. Some factories, on the contrary, use cheap short-term oil prevention to deal with the long-term storage of export equipment. As a result, the oil film is initialized or volatilized during shipping, and it is already rusted when it arrives in the hands of customers, resulting in huge claims losses. The root cause of these problems is not that the anti-rust product itself is not good, but that the product is not accurately matched according to the actual protection cycle.
The core value of the Hank BS-400 series is that it breaks the simple thinking of "one bottle universal" and covers the whole cycle from short-term protection to storage with a complete product line. This series adopts a unified formula platform, but by adjusting the type of film-forming agent, volatilization speed, oil film thickness and the compounding ratio of anti-rust additives, the performance is divided in steps. Take the three common models as an example: BS-401 is a quick-drying short-term oil-proof oil, which can be dried within a few minutes after spraying or dipping, forming a thin transparent soft film that neither sticks to hands nor absorbs dust. It is suitable for short-term rust prevention from 7 days to 90 days; BS-402 is a medium-cycle soft film anti-rust oil. The oil film is flexible and has certain self-healing properties. It is suitable for storage in indoor warehouses or under simple shading conditions for 90 to 180 days; BS-403 is a hard film storage oil. After drying, it forms a tough translucent film layer that can withstand severe temperature changes, high humidity and salt spray erosion. It is suitable for long-term storage for more than 180 days, especially for export sea or open storage scenarios.
The BS-400 series uses a composite base oil of refined mineral oil and synthetic esters, combined with a variety of high-efficiency anti-rust agents and new film-forming resins. This formula design allows the oil film to generate strong physical and chemical adsorption on the metal surface, forming a dense protective layer. Different anti-rust agent combinations have different shielding effects on water vapor, oxygen and ions. BS-400 adjusts the combination ratio to make short-term, medium-term and long-term protection products have their own focuses: short-term protection pays more attention to volatility and low residue, and long-term protection pays more attention to film strength and corrosion inhibition persistence. It is this "same platform, multi-layer" formula logic that allows users to switch protection needs without changing suppliers, and without worrying about compatibility between different products.
In order to help field engineers make quick decisions, the model of the Hank BS-400 series can be selected according to the following logic: the protection period is within 7 days, and the workpiece is frequently flowing, choose BS-401, pay attention to control the oil film thickness of 3 to 5 microns; the protection period is 7 to 90 days, the storage place is indoor and the surface is required to be non-stick, choose BS-401; if you allow a slight oil sensation and the ambient humidity is large, you can choose BS-402, the oil film thickness can be controlled at 8 to 15 microns; the protection period is 90 to 180 days, and there may be temperature and humidity fluctuations in the storage environment, choose BS-402 directly; the protection period is more than 180 days, or if you need to ship or store in the open air, you must choose BS-403, and the oil film thickness is recommended to reach 15 to 25 microns. In addition, if the workpiece has blind holes, internal cavities, or complex pipelines, it can also be combined with a gas phase rust inhibitor, while the auxiliary model BS-405 in the BS-400 series can cooperate with the oil film and rely on volatile corrosion inhibitor molecules to provide additional protection for surfaces that are not easy to coat in a confined space to avoid cavity failure.
In terms of construction technology, the Hank BS-400 series also emphasizes standardized operation. The recommended process is "pre-treatment oiling film thickness inspection packaging and storage". Before applying oil, it is necessary to ensure that the metal surface is free of acid, alkali, salt and moisture. Especially for workpieces processed by cutting fluid, if the emulsifier, extreme pressure agent and other ingredients in the cutting fluid remain on the surface, it will seriously affect the adhesion of the anti-rust oil, and even react with anti-rust additives, resulting in a significant reduction in the anti-rust period. The correct way is to spray or ultrasonic cleaning with alkaline cleaning agent first, and then dry it with compressed air or hot air. If there is a water film on the surface of the workpiece that is difficult to completely remove, the BS-401W model with water replacement performance in the BS-400 series can be preferred, which can squeeze out the water when the oil film touches the metal surface, thereby reducing the process and improving the efficiency. In terms of oiling methods, it is recommended to dip coat small and medium-sized parts, cover them evenly with bath liquid, and allow excess oil to flow back by hanging; spraying is recommended for large structural parts, which can flexibly control the local thickness; on-site recoating is suitable for brushing, especially for strengthening the rusty parts such as welds and edges. The thickness of the oil film is a key variable in determining the length of the rust prevention period. If the oil film is too thin, it may break at the microscopic spikes. If it is too thick, it wastes material and increases the difficulty of removal. Therefore, qualified enterprises can use a paint film thickness gauge for sampling to ensure that the actual film thickness falls within the recommended range of the product.
From an economic point of view, the classification scheme of the Hank BS-400 series can also significantly reduce the comprehensive cost of use. We might as well calculate an account: if a company handles 100,000 small workpieces a year, if all the high-performance hard film sealing oil is used, each piece will consume an additional 0.5 yuan in solvent cleaning fees and 0.3 yuan in operating man-hours, which alone will cost an additional 80,000 yuan per year; and if all the fast-drying short-term oil protection is used, once long-term storage is required, the cost of rework and rust removal is immeasurable. By dividing the workpiece into short-term protection, medium-term protection, and long-term protection according to the actual protection cycle, and selecting BS-401, BS-402, and BS-403 respectively, the company can not only get the right protection for each product, but also spend every cent of the protection cost on the blade.
In practical applications, the BS-400 series also shows significant flexibility. Some customers want to quickly switch between different models on a rust-proof production line. Hank's tank fluid design supports multi-tank sharing, which can be achieved by simply changing the oil and adjusting the spray parameters. For those orders whose protection period is not fixed, a mixed strategy can even be adopted: use BS-401 for short-term rust prevention first. If the order is found to be delayed or needs to be transferred to long-term storage, there is no need to completely remove the original oil film. You can directly spray BS-403 hard film oil on the surface of BS-401. Due to the fact that the BS-400 series belongs to the same formulation system, there will be no incompatibility, peeling or separation between the two membranes. This flexibility of "short-term anti-upgrade storage" is difficult to achieve in traditional single product solutions. Conversely, if the hard film workpiece of the BS-403 needs to be reprocessed, it can also be easily removed by a special environmentally friendly film remover without damaging the base metal.
When using the Hank BS-400 series, there are sometimes some abnormal conditions. For example, the oil film turns white or emulsified, usually because of the residual moisture on the surface of the workpiece during coating. At this time, the drying process of pre-treatment should be strengthened, or the BS-401W water replacement product should be used instead. For another example, the hard film cracks in a low temperature environment, often because the film layer is too thick or the temperature difference is too large. The amount of oil should be appropriately reduced, and the workpiece should be fully cured after oiling before low temperature storage. For another example, the anti-rust period does not meet expectations. The common reason is that the surface of the workpiece is not cleaned, or the packaging material absorbs moisture and is damaged. By checking one by one, most problems can be solved quickly.
It is worth mentioning that the friendliness of the Hank BS-400 series to the environment and operators has also been systematically optimized. It uses low-odor, low-aromatic environmentally friendly solvents, which reduces the concentration of volatile organic compounds in the workplace and reduces the irritation to the respiratory tract. At the same time, the product does not contain heavy metals and halogen additives, and complies with the requirements of RoHS and Reach regulations, which clears the barrier for customers' compliance review when exporting. For factories that value production safety, the high flash point design of the BS-400 series further reduces the fire hazard, making it widely used in machine shop, assembly shop and warehouse logistics area.
In addition, the Hanke BS-400 series is also quite solid in the verification data of anti-rust performance. According to the laboratory's salt spray box test, the BS-401 can be rust-free for 24 to 48 hours in a neutral salt spray environment, which can meet most indoor short-term protection scenarios; the BS-402 can reach 72 to 96 hours under the same conditions, corresponding to storage protection for about half a year; the BS-403 can pass the neutral salt spray test for more than 120 hours, and after proper packaging, it can cope with the harsh shipping environment. Of course, the actual rust prevention period will also be affected by multiple factors such as packaging materials, temperature and humidity fluctuations, and initial cleanliness, but the data given by the BS-400 series can be used as a basic reference for selection.
To sum up, from short-term protection to storage is not a simple multiple choice question, but a path that requires system matching based on protection cycle, environmental conditions, follow-up processes and cost-effectiveness. The Hank BS-400 series truly realizes the goal of "accurately matching needs" through clear model layers, excellent technical specifications and flexible construction adaptation. It allows every drop of anti-rust oil to play its due value, so that every metal workpiece can be reliably, economically and safely protected during the long journey from factory to unsealing. In today's high-quality manufacturing industry, choosing a scientific anti-rust solution like the Hank BS-400 series is not only a necessary measure to improve product quality, but also an important strategy to reduce operating costs and enhance customer trust.
