Custom Air Releasing Valve for Microwave Lunch Boxes

Air releasing valves used in lunch boxes usually consist of two functional components: an air inlet valve and an air outlet valve. This custom valve project dates back to 2014, when our customer was developing a lunch box designed for office workers who frequently bring meals from home.

For many office employees, reheating food in a microwave during lunchtime is a daily routine. Traditionally, users need to open the lunch box lid before heating. However, when multiple people heat food at the same time, strong food odors can spread in the microwave and affect other meals.

To solve this problem, our customer designed a lunch box lid with an integrated air releasing valve, allowing users to heat food without completely opening the lid.

However, from an engineering perspective, microwave heating requires both air intake and air release to maintain pressure balance inside the container. Initially, the customer considered using a duckbill valve, but since duckbill valves are one-way valves and the installation space on the lid was limited, the solution was not suitable.

After several technical discussions with our engineering team, we recommended using a cross-slit silicone valve with an undercut retention structure. This design allowed the valve to be securely snapped into the lunch box lid while solving the limited assembly space issue.

During the development stage, we produced prototype tooling and conducted multiple tests to optimize the silicone hardness and slit dimensions. Through these trials, we helped the customer achieve a valve design that provided stable performance and reliable airflow control.

The valve is manufactured from food-grade silicone material and features a removable structure, ensuring both food safety and easy cleaning for users.

At Hopewell, we are committed to supporting our customers in developing innovative products. We look forward to helping create more solutions that improve everyday life through reliable silicone valve technology.

Hopewell has over 10 years of experience in designing and manufacturing custom silicone valves for a wide range of consumer and industrial applications.

Contact our team today to discuss your project and explore the right valve solution for your product.