The sealing design of portable tableware

Analysis of the Sealing Design of Portable Tableware

The sealing design of portable tableware aims to prevent liquid leakage, food spillage and the spread of odors. The core lies in achieving efficient sealing through structural innovation, material selection and process optimization. The following analysis is conducted from the aspects of sealing principles, key design elements and typical application scenarios.

First, the core principle of sealing design

Physical barrier

Principle: By the deformation of elastic materials (such as silicone and rubber), gaps are filled to form a physical barrier. For instance, when silicone rubber sealing rings are under pressure, they undergo elastic deformation, filling the tiny gap between the container and the lid, and preventing liquids or gases from passing through.

Case: In the threaded sealing structure of the thermos cup, the silicone rubber sealing ring, after being squeezed by the thread, forms a tight fit with the cup mouth, and the leakage rate can be reduced to less than 0.01ml/min.

Air pressure balance

Principle: Balance the internal and external air pressure through a check valve or a breathable membrane to prevent seal failure caused by pressure difference. For example, the air pressure balance valve releases the internal high pressure at the moment the cover is opened to prevent liquid splashing.

Case: The breathable membrane design of the sports water bottle can increase the speed of air pressure balance by three times while preventing water evaporation.

Multiple sealing structure

Principle: By combining physical barriers with air pressure balance, a dual protection is formed. For instance, the combined design of the sealing ring and the snap can simultaneously cope with vibration and pressure changes.

Second, key design elements

Selection of sealing materials

Silicone: It has a wide temperature resistance range (-40℃ to 230℃) and good elasticity, making it suitable for food contact scenarios. For instance, the compression set rate of silicone rubber sealing rings is less than 15%, and they can maintain their sealing performance for a long time.

Rubber: It has strong wear resistance but poor heat resistance and is suitable for non-high-temperature scenarios. For instance, nitrile rubber sealing rings have excellent oil resistance, but they are prone to aging at high temperatures.

Thermoplastic elastomer (TPE) : It combines the properties of both plastic and rubber, is recyclable, but has a relatively high cost.

Sealing structure form

Threaded sealing: Sealing is achieved through threaded fit and sealing rings, and is suitable for cups and kettles. For instance, the double-thread design can make the force on the sealing ring more uniform, reducing the risk of leakage by 50%.

Snap-fit sealing: Sealing is achieved by locking the snap-fit and adhering it to the sealing ring. It is suitable for lunch boxes and bento boxes. For instance, the three-point snap-on design can make the sealing pressure distribution more uniform, and the opening and closing life can reach over 100,000 times.

Flap sealing: Sealing is achieved by the adhesion of the flap to the sealing strip, and it is suitable for seasoning boxes and snack boxes. For instance, the magnetic flap design can increase the adhesion pressure of the sealing strip by 40%, providing a better leak-proof effect.

Optimization of sealing process

Injection molding: The one-piece molding process can reduce seams and lower the risk of leakage. For instance, the injection molding accuracy of silicone rubber sealing rings can reach ±0.05mm, ensuring a perfect fit with the container.

Ultrasonic welding: Materials are fused together through high-frequency vibration to form a seamless connection. For instance, the ultrasonic welding strength of plastic lunch boxes can reach 80% of the base material, and there is no risk of leakage.

Coating treatment: Apply a hydrophobic coating on the sealing surface to reduce liquid residue. For instance, the nano-hydrophobic coating can make the contact Angle exceed 150°, and the liquid will fall off at the slightest shake.

Third, verification methods for sealing design

Leakage test

Pressure test: Fill the container with a pressure of 0.5MPa and observe whether there is any leakage within 1 minute. For example, the leakage of qualified products should be less than 0.05ml/min.

Vibration test: Simulate transportation vibration (frequency 10Hz, amplitude 1mm), and check for leakage after continuous operation for 1 hour. For example, the leakage rate of qualified products should be less than 0.1ml/min.

Opening and closing life test

Cyclic test: Simulate the opening and closing actions in actual use and record the attenuation of sealing performance. For instance, the opening and closing life of a qualified product should reach over 10,000 times, and there should be no significant change in the leakage rate.

Extreme environment testing

High-temperature test: Place in an environment of 80℃ for 24 hours to check whether the sealing material is deformed or aged. For instance, the dimensional change rate of high-quality silicone rubber sealing rings at high temperatures should be less than 2%.

Low-temperature test: Place in an environment of -20℃ for 24 hours to check whether the sealing material becomes brittle or cracked. For example, the low-temperature impact strength of qualified products should reach above 10kJ/m².

Fourth, typical application scenarios and sealing requirements

Outdoor sports scene

Requirements: leak-proof, impact-resistant, and resistant to extreme temperatures.

Design: It adopts double-layer threaded sealing + silicone rubber sealing ring, and is combined with a pressure balance valve to ensure no leakage on bumpy roads.

Office commuting scene

Requirements: Portable, easy to open and close, and odor-proof.

Design: It adopts a magnetic flap cover and TPE sealing strip, combined with a hydrophobic coating, to achieve one-handed operation and quick cleaning.

Children's usage scenarios

Requirements: Safety, prevention of accidental opening, and durability against drops.

Design: It adopts three-point clips and food-grade silicone sealing rings, combined with anti-slip textures, to reduce the risk of accidental opening and damage from drops.