API 7-2 Update



The June 6, 2017 compliance date for the new American Petroleum Institute’s (API) 7-2 Specification for Rotary Shouldered Connection Inspection has arrived.

To help, we’ve highlighted some key points below:

• Resolution of IndicatorsGagemaker-863-indicator  

Indicator resolution requirements have been updated for all lead, height, and taper gages. (API 7-2 7.4.1, 7.5.2, 7.6*) Now gages with alternate indicators may not meet the new API requirements and must be replaced. Here are the new inspection elements and their new required resolutions:

Element to Inspect
New Indicator Resolution

We highly recommend that you check your gages ASAP.  To help, we’ve provided a table to help you determine the correct indicator for your gages. Please note we’ve provided two model numbers for the indicators in some instances as the models have changed over the years, but either is compliant. Most of our indicators have the model number on the indicator face. Also note that we’ve shown gages which we may not manufacture any longer but are still in the field.

Click on the indicator image in the table to enlarge

Element to InspectAPI 7-2 Resolution RequirementExternal/Internal/Both MeasurementModel NumberInch Indicator Metric IndicatorResolutionTravel
Height.0005"/.013mmInternalTH-3009-RSC863 or 2515SGA

Lead.0005"/.013mmBothLG-5002, LG-5003, LG-6001, LG-600280-0403 or 1571SSGA


Taper.001"/.025 mmExternalET-7003, ET-7005, ET-7007882L or 2416SGA w/ lifting lever


Taper.001"/.025 mmInternalIT-6000882I or 2514SRGA




*The 2056 indicator for the IT-6000 for metric threads requires a slight modification to fit the gage.


If you do find that you need replacements, please ask about our Trade-in Program or submit a Trade-in Request.


• New Bevel Diametersgagemaker-api-7-2-update-drawings

Tables for connection bevel diameters have changed. (API 7-2 5.2.2)

• Drawings Require New Angles

All RSC box drawings now require a 30° max back-of-the-box angle. (API 7-2 6.3.3 Fig. 10)


• New emphasis on the effects of lead errorGagemaker-LG-6001-on-part

The effects of lead error on standoff and pitch diameter can no longer be ignored.  Greater emphasis has been placed on mandatory lead inspection. (API 7-2 7.2.1). Lead has a tremendous effect on pitch diameter, and consequently, on standoff as well. The effects of lead error on standoff is more significant than most people realize. For a 2″ TPF rotary shouldered connection, a 0.001″ change in pitch diameter will alter standoff by 0.006″. On the other hand, 0.001″ of lead error correlates to a 0.0035″ change in pitch diameter and a 0.0208″ change in standoff. In other words for this thread, lead error affects standoff over three times as much as the same amount of pitch diameter error. Note that on rotary shouldered connections that just 0.001″ of lead error can cause you to exceed all of your standoff tolerance.

The correlation between PD and stand-off is as follows:  Divide 12 by the Taper per Foot…and that will yield the effect on stand-off, for every 0.001” change in pitch diameter.

Example:  12 / 2 TPF = 6. So, for every 0.001” change in measured Pitch Diameter, the stand-off will be changed by 0.006”.


• Gap on Hand-tight Parts Allowedgageamaker-7-2gap-allowed

If all of your element inspections are within tolerance, a gap between shoulders is allowed when parts are made-up hand-tight. A gap is still prohibited when parts are made up under proper torque. (API 7-2 7.2.3 Fig. 14)

*API (American Petroleum Institute) maintains 685 standards and recommended practices. Many have been incorporated into state and federal regulations; as well as adopted by the International Organization for Standardization.


If you need a refresher on how to inspect RSC thread elements, you can always visit our Youtube channel or check out the video below: