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    10 Products

    Threaded Ring Gauges with Calibration Certificate

    Not only were these gauges calibrated in a lab, but they also come with a certificate that's traceable to NIST. The certificate, sometimes called a test report and long form certificate, details the tested measurements. They’re for checking a part’s external threads to ensure they fall within tolerance.
    A part is within tolerance if it’s easy to thread a go gauge onto the part but difficult to thread a no-go gauge more than two turns. Inspect faster by holding more than one ring gauge with a threaded ring gauge holder.
    Class X Gauges
    Image of Product. Front orientation. Ring Gauges. Threaded Ring Gauges with Calibration Certificate.
    Image of Attribute. Front orientation. Threaded Ring Gauges with Calibration Certificate.
    Go Gauge—Go gauges check the maximum external thread size.
    No-Go Gauge—No-go gauges check the minimum external thread size.
    For Thread Fit—Threads have different classes of fit. Thread fit designates the tightness or looseness of the mating threads. For example, inch threads with a 3A fit have tighter tolerances than threads with a 2A fit.
    Go Gauge
    No-Go Gauge
    Thread
    Size
    Thread
    Direction
    Hardness
    Material
    Certificate Type
    Pitch Dia.
    Tolerance
    Each
    Pitch Dia.
    Tolerance
    Each
    For Class 2A Unified Standard Thread Fit
     
    UNC Thread
    5/16"-18
    		Right Hand
    		Rockwell C60Tool Steel
    		Calibration Certificate Traceable to NIST-0.0003" to 0"3160A16700000000" to 0.0003"3160A2690000000
     
    For Class 3A Unified Standard Thread Fit
     
    UNC Thread
    5/16"-18
    		Right Hand
    		Rockwell C60Tool Steel
    		Calibration Certificate Traceable to NIST-0.0003" to 0"3160A1660000000" to 0.0003"3160A268000000
     

    Threaded Ring Gauges

    Image of Product. Front orientation. Threaded Ring Gauges.
    Check a part’s external threads to make sure they fall within tolerance. You can use these for bolts, threaded rods, bits, and more. All gauges come with a manufacturer’s certificate of accuracy, also known as a certificate of compliance or a short form certification, that verifies the thread sizes are within tolerance.
    The part is within tolerance if it’s easy to thread a go gauge onto, but difficult to thread a no-go gauge more than two turns. Use a threaded ring gauge holder to keep two gauges on hand at once for faster inspection.
    Go Gauge—Go gauges check the maximum external thread size.
    No-Go Gauge—No-go gauges check the minimum external thread size.
    For Thread Fit—Threads have different classes of fit. Thread fit designates the tightness or looseness of the mating threads. For example, inch threads with a 3A fit have tighter tolerances than threads with a 2A fit.
    Go Gauge
    No-Go Gauge
    Thread
    Size
    Thread
    Type
    Hardness
    Material
    Thread
    Direction
    Choose a Thread Fit
    Pitch Dia.
    Tolerance
    Each
    Pitch Dia.
    Tolerance
    Each
    Class X Gauges
    5/16"-18
    		UNC
    		Rockwell C60Tool Steel
    		Right Hand
    		Unified Standard Class 2A, Unified Standard Class 3A
    		-0.0003" to 0"2356A32400000000" to 0.0003"2356A4240000000
     

    Left-Hand Threaded Ring Gauges

    Test if the left-hand threads on parts fall within tolerance. These gauges are often used with parts such as screws, bolts, and threaded rods. All come with a manufacturer’s certificate of accuracy, also known as a certificate of compliance or a short-form certification, that verifies the thread sizes are within tolerance.
    The part is within tolerance if it’s easy to thread a go gauge onto, but difficult to thread a no-go gauge more than two turns. Use a threaded ring gauge holder to keep two gauges on hand at once for faster inspection.
    Class X Gauges
    Image of Product. Front orientation. Ring Gauges. Left-Hand Threaded Ring Gauges.
    Go Gauge—Go gauges check the maximum external thread size.
    No-Go Gauge—No-go gauges check the minimum external thread size.
    For Thread Fit—Thread fit designates the tightness or looseness of mating threads. For inch threads, the higher the class number, the tighter the fit. These metric-threaded ring gauges are class 6g, which is comparable to the fit of those with unified standard class 2A threads.
    Go Gauge
    No-Go Gauge
    Thread
    Size
    Thread
    Direction
    Hardness
    Material
    Certificate Type
    Pitch Dia.
    Tolerance
    Each
    Pitch Dia.
    Tolerance
    Each
    For Class 2A Unified Standard Thread Fit
     
    UNC Thread
    5/16"-18
    		Left Hand
    		Rockwell C60Tool Steel
    		Accuracy Certificate Traceable to NIST-0.0003" to 0"8399N3500000000" to 0.0003"8399N770000000
     

    Left-Hand Threaded Ring Gauges with Calibration Certificate

    Calibrated in a lab and backed by a certificate traceable to NIST, these gauges check if left-hand threads fall within tolerance. The certificate, sometimes called a test report and long-form certificate, details the tested measurements. Use these gauges on screws, threaded rods, and other parts with external threads. For faster tests, hold more than one ring gauge with a threaded ring gauge holder.
    Your part is within tolerance if it’s easy to thread a go gauge onto it but difficult to thread a no-go gauge more than two turns.
    Class X Gauges
    Image of Product. Front orientation. Ring Gauges. Left-Hand Threaded Ring Gauges with Calibration Certificate.
    Image of Attribute. Front orientation. Left-Hand Threaded Ring Gauges with Calibration Certificate.
    Go Gauge—Go gauges check the maximum external thread size.
    No-Go Gauge—No-go gauges check the minimum external thread size.
    For Thread Fit—Thread fit designates the tightness or looseness of mating threads. For inch threads, the higher the class number, the tighter the fit. These metric-threaded ring gauges are class 6g, which is comparable to the fit of those with unified standard class 2A threads.
    Go Gauge
    No-Go Gauge
    Thread
    Size
    Thread
    Direction
    Hardness
    Material
    Certificate Type
    Pitch Dia.
    Tolerance
    Each
    Pitch Dia.
    Tolerance
    Each
    For Class 2A Unified Standard Thread Fit
     
    UNC Thread
    5/16"-18
    		Left Hand
    		Rockwell C60Tool Steel
    		Calibration Certificate Traceable to NIST-0.0003" to 0"7836N3500000000" to 0.0003"7836N770000000
     
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