08-30-2021, 09:02 AM
A fixed head leak tester is a procedure used to determine if an object, product, or system functions within a specified leak limit. A leak occurs when a gas or liquid flows through an object via an imperfection or manufacturing defect such as a hole, crack or weak seal. These imperfections create high- and low-pressure zones within a product, forcing the gas or liquid to flow from the high-pressure area to the low-pressure area. The primary leak test method discussed in this article uses pressurized air to identify leaks.
Considerations for leak testing:
What is the intended use of the part?
What medium is being constrained inside or outside of a part? A medical device manufacturer designing an IV set may try to keep saline inside the IV set. An automotive manufacturer may have designed their manifold to prevent exhaust gases from escaping the exhaust manifold. An acceptable hole or porosity in these parts is contingent upon the application by which a leak limit will be determined.
Medium
During the design and development of a product it is important to consider the test criteria to ensure a part has been manufactured correctly. Design criteria such as test pressures, access ports, shared walls or vessels, internal test volumes, and leak rate specifications all have an impact on the complexity and time required for a leak test. How the object connects to a leak test system helps to determine what kind of leak test will be run on the object. A fully enclosed object with no port to fill the item, such as a waterproof enclosed electronic device, requires a chamber test which includes a sealing fixture. An object with one port or opening, such as a catheter, can be directly connected to the front port of a leak tester without a fixture.
Conveyor has been a staple in the materials handling industry for decades. As the demand for reduced cost, increased throughput and integrated automation grows, so does the need for conveyor systems of all types.
Regardless, traditional belt conveyor is a simple, time-tested technology. It’s less expensive than powered buffer conveyor, it provides a more stable surface, and it can convey a variety of products. Poly bags, envelopes and electronics are examples of products handled easily by belt conveyor that are often too small or too light to be conveyed directly on rollers.
Roller conveyorLine-shaft conveyor is the least expensive type of roller conveyor. It has been in the market for a long time, but it has limitations. Even though line-shaft flexible conveyor costs less, explains Don Erickson, director engineering for Automotion, it is parts-intensive, which leads to high maintenance requirements.