Whether a manufacturing plant specializes in washing machines or agricultural equipment, they will require screws, nuts and bolts to assemble products. Ring gages help ensure that each metal component meets the precise thread specifications.
Our guide will explore the best practices for calibrating thread ring gages, enabling you to maintain reliable results. We’ll also discuss why you should use a set plug along with your ring gage during calibration. Read on to discover expert insights into the procedure and enhance accuracy within your applications.
What Is a Thread Ring Gage?
Thread ring gages are essential to manufacturing operations. These ring-shaped pieces of equipment check the external dimensions of components, namely the angle, pitch and diameter. Technicians will record these thread measurements and compare them against international standards/set-plugs.
If a thread falls outside of the specifications, the component is properly adjusted to meet optimum specifications. Prioritizing this process helps to ensure that internal and external threads fit together, and the load is balanced.
The Thread Ring Gage Calibration Procedure
Frequently calibrating your thread ring gages ensures the accuracy of results over time. In addition, the calibration process helps to spot signs of wear and tear early so you can maintain the integrity of your ring gage. Here’s a brief breakdown of how to calibrate thread ring gages for optimum reliability:
Match the ring gage with the set plug: Ensure an accurate match by ensuring the pitch diameters and size of both components match. Once you select an appropriate pair, coat the plug gage with light viscosity oil.
Inspect the ring gage for discrepancies: Dents, raised metal edges and embedded metal filings will impact the reliability of the calibration. Maintain greater accuracy by carefully inspecting the ring gauge before each use.
Ensure the set-plug is in tolerance/calibrated: Use the calibrated set-plug, obtain the correct level of drag on the full form and truncated portions of the calibrated set-plug. If the optimal level of drag is obtained, the calibration is complete. If the drag is not optimal, move on to the next step.
Prepare the functional adjustment: A ring gage has two screws — a locking screw and an adjusting screw. Loosen the locking screw by turning it in a counterclockwise motion. Follow this step by turning the adjusting screw in a clockwise direction to obtain a more lose drag. Turn the adjusting screw counterclockwise to obtain a more snug drag. Tighten locking screw once optimum drag is obtained.
Obtain the correct level of drag: Ensure the appropriate amount of drag by rotating the adjusting screw counterclockwise (Tighten) or clockwise (Loosen) while turning the ring on the thread setting plug. By adjusting the ring gage you will obtain the optimal amount of drag, thereby, completing the calibration.
Double-check the drag: Once you’ve established the correct level of drag, recheck a second time with your calibrated set-plug. If you again have the optimal level of drag, the calibration is complete.
Seal the adjustment screws: Once you’ve correctly set the locking and adjusting screws, seal them with wax to ensure they do not move future use.
Calibrating a thread ring without a set-plug: It is essential to accompany all thread rings with matching set-plugs. Most calibration labs will have matching set-plugs for standard size thread rings. When purchasing a special size thread ring, to achieve optimal functional calibrations, it is essential to purchase the matching set-plug to accompany the ring to be calibrated and then used to calibrate the thread ring. Without a matching set-plug, only a non-functional measurement of the pitch diameter and can be achieved leaving it up to the owner to determine if this measurement meets their specifications.
Requirements for Calibrating Thread Ring Gages
All ring gages must meet national or international specifications. The American National Standards Institute (ANSI) and The American Society of Mechanical Engineers (ASME) determine the calibration standards in the United States. Here’s an overview of the criteria:
Trained personnel must inspect all gages to ensure they comply with the specified specifications and tolerance guidelines
Reference standards must be traceable to System International (S.I.) units
Gages will also need to undergo extensive inspections to certify they meet the ANSI and ASME requirements
Why Follow ASME/ANSI Recommendations?
Following the meticulous guidelines of the ASME/ANSI standards is worth the extra legwork. Here are some reasons why:
Legal requirement: Following ASME/ANSI guidelines means your ring gauge meets industry standards. For many businesses, meeting sector regulations is a prerequisite for legal operations.
Enhanced credibility: Clients are more likely to trust measurements that comply with industry regulations. Giving clients extra peace of mind is a drawcard for increased business.
International acceptance: By complying with standards set by government-recognized bodies such as ISO, you show the world that your products are trusted.
Why Should I Buy a Set Plug With My Thread Ring Gage?
When purchasing a thread ring gage, sales representatives may prompt you to add a set plug to your order. Here are some reasons why it’s necessary to buy both components:
Calibrating a thread ring without a set-plug: It is essential to accompany all thread rings with matching set-plugs. Most calibration labs will have matching set-plugs for standard size thread rings. When purchasing a special size thread ring, to achieve optimal functional calibrations, it is essential to purchase the matching set-plug to accompany the ring to be calibrated and then used to calibrate the thread ring. Without a matching set-plug, only a non-functional measurement of the pitch diameter and can be achieved leaving it up to the owner to determine if this measurement meets their specifications.
Account for all measurements: Factors such as flank angle, lead, root clearance and helical offset are important to ensure a functional fit. Set the plugs to measure these aspects for enhanced reliability.
Remove subjectivity: What constitutes as a firm or loose grip is subjective — we need more uniform methods to ensure consistency. Plug gages help to create a more uniform standard for accuracy.
Consequences of Uncalibrated Ring Gauges
Taking the time to calibrate your gauges is in everyone’s best interests. Here are some situations that could occur when using incorrectly uncalibrated tools:
Quality control: Uncalibrated ring gauges result in inaccurate measurements, ultimately leading to faulty components. Inconsistencies with quality affect product safety and the company’s reputation.
Excessive scrap materials: Accuracy is paramount for many industries — especially the aerospace and automotive sectors. Incorrectly calibrated ring gauges result in faulty components, which inevitably become scrap metals.
Safety issues: If components with inaccurate threads enter the market, they could pose a safety risk to manufacturing teams and users. Workplace hazards prevent seamless workflows and have the potential to result in costly lawsuits.
Certification challenges: Submitting components with incorrect measurements will likely cause delays with certification. This could prevent businesses from coordinating with other companies.
Additional costs: Between reworking metal components or sending faulty elements to the scrap pile, uncalibrated ring gauges result in various additional costs. These expenses add up and have a significant impact on your bottom line.
Contact the Experts at Garber Metrology for Thread Ring Gauge Calibration
Ring gauges will experience subtle changes over time, impacting the reliability of results. Regular calibration mitigates inaccuracies and ensures greater consistency. If you’re looking for expert calibration efforts, Garber Metrology offers the tools you need. Our fast in-house calibration services also allow you to drop off your ring gauges at our offices and collect them within five business days.
