How to Size Flare Tee Fittings
- 1). Press the "On/Off" button to turn a pair of digital calipers on. Push the two large jaws together to zero out the display on the calipers.
- 2). Open the two large caliper jaws and insert the threads of a male flare fitting in between them. Close the jaws on the male fitting. Read the size on the digital display for the outside diameter.
- 3). Measure a female flare fitting by placing the small jaws inside the opening and spreading the jaws apart until they touch both internal sides of the fitting. Read the size on the digital display for the inside diameter.
- 4). Place a thread pitch gauge on the threads of a flare fitting that appears to have fingers that will fit into the threads. Try a larger pitch gauge if the threads are wider or a smaller pitch gauge if the threads are closer together until the pitch gauge fits into the threads entirely. Read the measurement on the pitch gauge that fits the threads.
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