A small can sealing machine is designed for small and medium-sized enterprises (SMEs) to handle their operations. These entrepreneurs typically manage all aspects of their business on their own, including preparing raw materials, manufacturing products, finding customers, selling products, shipping (to retailers or consumers), managing finances, and maintaining equipment. Given that small business operators often handle every task themselves, they must focus most of their time on managing operations and customer relations. Additionally, they often have limited capital and thus cannot afford multiple machines. Consequently, the machinery must be versatile, durable, and not overly specialized. For maintenance, small operators typically have little time to care for machinery, so it needs to be exceptionally durable and require minimal upkeep. For small can sealing machines used in food packaging, in addition to meeting the above characteristics, it is crucial that the sealing standards meet international standards to facilitate future export opportunities as the customer base expands. Key Features Needed for Small Can Seamer Machines Considering the differences between small and large-scale manufacturing businesses, designing machinery for SME use should address the following: 1. Ease of Use and Maintenance: The machine should be easy to operate and maintain without requiring specialized knowledge or technical expertise. 2. Cost Efficiency: It should require minimal maintenance time and operate most efficiently. 3. Energy Efficiency: Low energy consumption is important since energy costs accumulate over time. 4. Minimal Parts: Fewer parts are preferable, provided they maintain high operational efficiency. 5. Continuous Operation: The machine should be capable of continuous operation as needed by the user. 6. Safety: The machine should be safe for operators. 7. Environmental Friendliness: It should produce minimal pollution. 8. Lubricant Usage: Minimal lubricant use to avoid contamination of food products. 9. Durability: The machine should have a long lifespan and a short payback period. Design Considerations for Small Can Seamer Machines 1. Double Seam Quality: The machine must achieve the required double seam quality or meet the specified standards. 2. Flexibility: It should be adjustable for different can diameters and heights, and accommodate frequent changes in can and lid sizes easily and quickly. 3. Size: The machine should not be excessively large. 4. Ease of Operation: It should be user-friendly with minimal training required and not depend on specialized technicians. 5. Smooth Operation: The machine should operate smoothly with low vibration, minimal noise, and without the need for overly robust structures to support vibrations. Key Components of a Small Can Seamer Machine 1. Structure: This part determines the machine's appearance and performs several functions: Supports various working components. Absorbs forces, particularly vibrations during operation. Serves as the mounting base for the machine. 2. Working Parts: These are crucial for the machine’s operation: Chuck and Drive Mechanism: Typically involves a shaft connected to the chuck, driven by an electric motor. Lifter and Lifting Mechanism: The lifter plate is more complex, especially for machines designed for metal cans requiring standard body hook measurements. Considerations When Purchasing a Small Can Seamer Machine 1. Double Seam Quality: Ensure it can achieve the desired double seam quality. 2. Durability: The machine should be robust and use standard parts. 3. Corrosion Resistance: Components should be made from materials resistant to rust, such as aluminum or Stainless Steel Grade 304, 316. 4. Can Rotation: For rotating can models, ensure the cans rotate uniformly without wobbling. 5. Speed: For rotating can models: i. Manual machines should not exceed 750 RPM. ii. Semi-automatic or automatic machines should not exceed 1,400 RPM. For stationary can models (where rollers rotate around the chuck): i. Consider the centrifugal forces generated and ensure safety guards are in place to prevent accidents.

What to Do if a Can Dents When Chilled? Causes: Expansion of Water: When water inside the can turns into ice, it expands, causing increased pressure on the can walls, potentially leading to dents. Vacuum Effect: When water cools down near 3.98°C, it contracts, creating a vacuum inside the can, which can also lead to dents. Properties of Water: Volume and Density: Water has the highest density at 3.98°C. If the temperature deviates from this point, water expands. This is why ice floats on water. Expansion When Turning to Ice: Expansion When Freezing: Water increases its volume by about 9% when it transitions from liquid to solid (ice). Preventive Measures: Reduce Temperature Before Filling: Before filling the can with water, reduce the water temperature to 3.98-6°C to prevent vacuum formation when chilled. Use Flexible Containers: Use cans that can slightly expand, such as those with lids that adjust to internal pressure changes. Avoid Freezing: Avoid chilling the cans to the freezing point to prevent water from turning into ice and expanding. Additional Precautions: Check Can Quality: Use sturdy cans that can withstand the expansion of water. Control Transport Temperature: Maintain a moderate temperature during transportation to prevent water inside the cans from freezing. Proper Filling: Ensure there is enough space inside the can to accommodate water expansion if it freezes. By maintaining the quality of cans and preventing dents when chilled, customer satisfaction can be enhanced, and losses during production and distribution can be minimized effectively. Properties of Water Molecular Structure: Water Molecule (H2O): Consists of two hydrogen atoms and one oxygen atom connected by covalent bonds, with a 105° angle between them. Oxygen has a negative charge, and hydrogen has a positive charge. Hydrogen Bonds: Water molecules are connected by hydrogen bonds, forming a tetrahedral structure, which causes water to occupy more space when it freezes. Figure 1 Water Molecule Figure 2 Hydrogen bonds have a distance of 177 picometers, while covalent bonds have a distance of 99 picometers. Surface Tension: A clear example of hydrogen bonding is water's surface tension. We can observe that water droplets on a surface or on a lotus leaf are spherical, resembling a convex lens. When a glass is filled with water, the water surface bulges slightly above the rim. Without surface tension caused by hydrogen bonds, the water surface would be flat and level with the glass rim. Surface tension is a special property of water, stronger than that of other liquids except mercury, which is the only liquid element. Surface tension causes water to cohere and seep through every nook and cranny, even through holes and cracks in rocks. Thus, water plays a revolutionary role in shaping the Earth's surface. State Changes: At sea level atmospheric pressure, water is in a liquid state. Water changes to a gas (steam) when its temperature reaches the boiling point at 100°C and changes to a solid state when its temperature drops to the freezing point at 0°C. The process of state change in water involves the absorption or release of heat without a change in temperature, known as latent heat. The unit for latent heat is the calorie. 1 calorie is the amount of heat required to raise the temperature of 1 gram of water by 1°C. Therefore, adding 10 calories to 1 gram of water will increase its temperature by 10°C. Figure 3 Energy Required for Water State Changes Under atmospheric pressure at sea level, water will turn into a solid state at 0°C. When examining the graph in Figure 4, it is evident that water has the highest density at 4°C and remains in a liquid state. When water changes to a solid state at 0°C, its volume increases by approximately 9%. We can see this when a glass filled with water and placed in the freezer will overflow or cause the glass to break as the ice expands. Similarly, when water in rock crevices freezes, it expands, causing the rock to break and contributing to the weathering process, which produces sediment. Figure 4 Density of Water at Different Temperatures Water is a wonder of the universe. Generally, matter becomes denser when it transitions to a solid state. However, water becomes less dense when it changes to a solid state, which is why ice floats on water. If ice were denser than water, as air temperature drops, ocean water would freeze and sink to the ocean floor, making it impossible for organisms living on the ocean floor to survive. Therefore, water becoming less dense when it freezes is beneficial and conducive to life on Earth. When air temperatures drop below freezing, ice forms on the surface of the ocean, acting as an insulator to prevent the underlying seawater from losing heat and freezing completely. This allows marine life to survive in the ocean comfortably. Reference List Lesa 2022. สมบัติของน้ำ - LESA: ศูนย์การเรียนรู้วิทยาศาสตร์โลกและดาราศาสตร์. [online] Available at: https://shorturl.asia/mTIJ4 [Accessed 10 September 2022].

During COVID 19 Pandemic, LAZ-Step Ltd. pays attention to the safety of customers. Thus, COVID-19 protocol to be followed : All of our employees are fully vaccinated -two doses of Sinopharm and one dose of Moderna. 2. Employees must take monthly COVID19 tests from the laboratory facility and weekly self-testing ATK tests at the office. Covid test with LAB agency - MeDiSee, Vehicle Health Check Antigen Test Kit (ATK) - Self-test 3. Guidelines to prevent and control COVID 19 Providing alcohol gel station before entering the shop or touching commodities Must wear a face mask all the time in the facilities. Booking appointments in advance via phone call is recommended We have closely monitored the situation of the spread of the Coronavirus Disease (COVID-19) to fully take care of the safety of all employees and customers.