Articles tagged with "testing"

Production or fabrication processes can include dozens of stages to convert raw materials into finished goods. Regardless of the raw material or the finished product, one factor is constant - - most metals look alike.

Determining how much a metal can deform before thinning or fracture occurs is necessary for designing a reproducible forming operation. Testing the incoming sheet material is also essential because material properties may vary from coil to coil and affect the part quality and scrap rate. Understanding a material's plastic strain ratio and how to measure it are crucial in accurately establishing a material's formability.

A common thread runs through all effective troubleshooting approaches: the skill of observation. Learn to use it to your advantage.

This article discusses the capabilities and limitations of the two most common online tube monitoring test methods -- eddy current and ultrasonic. It discusses the types of flaws that each is capable of detecting, and shows photographs of three typical flaws -- one that was detected by ultrasonic, one by eddy current, and one by both. It concludes by showing that both methods should be used to provide the most comprehensive testing of welded tube.

Coordinate measuring machines have progressed since their inception in the 1970s.

The article discusses special considerations that must be kept in mind when hardness testing tube and pipe. Rockwell and Brinell are covered. Special considerations include surface finish, wall thickness, deflection, and internal supports.

Most manufacturers measure or test parts to verify that the parts meet quality standards. This conventional approach is time-consuming because testing adds steps and time to the production process. Furthermore, it is only as good as the sample size. A different approach to quality is to use a strain monitor to measure strain on the machine's frame. Comparing the strain with a reference (measured when the machine was known to be producing good parts) is a way to monitor the production process, and it doesn't require extra time or steps.

Manufacturing processes are prone to variances, resulting in manufactured products that do not conform to specifications. Dozens of types of electronic sensors and measurement systems are available that fabricators can use to verify that their products are not defective. Understanding what types of sensors are available and how they work are the first two steps in implementing electronic sensing devices for quality control.

Conventional quality control in tube bending operations usually means detecting the number of links on a tube bending mandrel. When such a system detects that a mandrel link is missing, it shuts down the system so personnel can discard the last bent tube and replace the mandrel. Unfortunately, the broken mandrel link usually is a symptom of a larger problem—one that may have produced poor-quality parts long before the mandrel broke.Another method, process variation monitoring, measures the tension on the mandrel and alerts the equipment operator when the tension changes. This lets the manufacturing personnel know that a problem is developing while it is still small and manageable.

Many manufacturers are familiar with using eddy current systems to inspect their sheet and tubular products. Eddy current testing (ECT) is a nondestructive electromagnetic test that offers a rapid examination to detect surface-breaking flaws or cracks. It can be applied easily to straight sections of both seamless and welded tubing. Tests can be performed online as part of the manufacturing process or offline as part of a supplier or customer quality assurance check.

Details are everything when you're manufacturing stainless steel pipe to exacting specifications.

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Starting a portable GTAW business takes a lot of hard work and dedication, but it also takes the basics of knowing how to start it. It's important to learn about what equipment you need, how to set it up, and how to evaluate your welding before you take your first job.

Leaders who oversee weld designs, materials, methods, personnel training, and manufacturing teams should promote welding performance by addressing quality and testing issues in contracts for any work. Total quality systems and weld acceptance criteria must be specific--specified for each contract--and adherence must be enforced without wavering. Acceptance criteria for welding should be agreed to in a face-to-face meeting before fabrication begins. Before a project begins, all parties should agree on the retention time for inspection and test records—including X-rays, personnel qualifications and other project data--and the contract should state the location and description of the records storage facility.

Although it takes effort and time, procedure qualification testing can help you standardize your welding procedures and know what to expect when it comes to the quality of your manufactured parts.