Testing Capabilities

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Middletown Tube Works is committed to producing the highest quality products with a focus on eliminating problems before they occur. We incorporate a full range of destructive and non-destructive tests to verify conformance to customer quality requirements throughout the product realization process.

Destructive Testing Capabilities

At each tube mill a full round of destructive testing is performed after every startup and weld-in and then at various intervals throughout the manufacturing process. Destructive tests performed can include:

Flare test Flare test	Flare Test: An 8" sample is cut and placed on top of a steel cone and a press is forced down on the top of the sample which flares out the bottom of the sample. A passed test shows no splits to the weld area.
Flatten test Flatten test Flatten Test: A 48" sample is flattened wall to wall the entire length of the sample. The force is applied 90 degrees to the weld seam. A passed test shows no defects to the weld area.
Reduction Test Reduction Test	Reduction Test: A die that is 70% smaller than the finished tube is pressed over the test piece allowing us to simulate the application of a number of our products. A passed test results in a reduced end with no collapse at the weld.
Lap Test Lap Test	Lap Test: A Lap Test is performed to assure proper strip edge alignment. A sample piece is cut on a high speed saw; the face of the sample is then polished and observed and measured under a microscope. A passed test shows edge mis-alignment no greater than 10% of the wall thickness of the tube.

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Non-destructive Testing Capabilities

At each production machine and at other designated points throughout the product realization process as specified by the control plan and or work instructions, material is measured to ensure that it meets all applicable specifications. Types of measurement include:

Eddy Current Testing Eddy Current Testing	Eddy Current Testing: On each tube mill an Eddy Current Tester uses electromagnetic induction to help detect flaws in weld integrity of the tubing without automatic alerting and marking of defective material when a variation is detected in the phase and amplitude of the measured current.
Variable Measurements Variable Measurements	Variable Measurements: Dimensional features such as sheet metal thickness, master coil and/or strip steel width, tube outside diameter, tube wall thickness, tube ID weld seam height (ID Flash), tube overall length and tube straightness are measured using calipers (both hand-held and table mounted), tape measures, micrometers and dial indicators. For specialty sized material, twist can also be measured using a digital protractor.
Attribute Measurements Attribute Measurements	Attribute Measurements: When required by customer end use specifications, custom made attribute check fixtures can be created or obtained for use as an additional check of tube end condition after manufacturing. Plug gages are used to verify tube ID size and ring gages are used to verify tube OD size.

All measuring equipment is calibrated on a set schedule either by the equipment manufacturer or their authorized agent, or in-house at Middletown Tube Works' quality laboratory. All in-house calibration is performed by trained personnel and items are checked against master samples that are verified to NIST by third party calibration sources at least annually.

Additionally, visual inspections are performed throughout the product realization process to ensure proper material condition and to monitor tube conditions such as surface condition, ID debris, end cut, material cleanliness and deterioration, etc.

If a test yields a result outside the acceptable specifications the machine is stopped, quality control determines the source of variation and makes needed corrections

Continual process improvement is an important component in Middletown Tube Works product realization process. The data derived from our tests are used to improve our manufacturing process, assuring superior quality products and a high level of customer satisfaction.

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