Thread Height

Thread height is the distance between the crest and the root of the thread, normal to the axis of the thread. Several issues are easily detected by simply inspecting thread height.

Proper thread height maximizes the performance of any threaded connection. Thread height inspection is required by API. Thread height affects the interchangeability and the integrity of the threaded assembly.

Gagemaker Thread Height Diagram

From detecting a chipped tool to preventing a connection from pulling apart under critical loads, inspecting thread height is valuable. Gagemaker manufactures thread height gages for both external and internal threaded connections for a variety of forms and sizes (tapered or straight). These gages provide immediate feedback on the integrity of your threads. Our thread height gages are designed for various thread types, forms, and sizes.

 

External Thread Height Gages

Gagemaker manufactures many models of external thread height gages. Specify the type of thread when ordering.

Some gages require a setting standard, see below for standards.

Contact point listed in description (e.g. T072) is included, but may specify other.

TH-0000-on-Pin-TRAN-

External Thread Height Gages
ConnectionMin. BoreIndicator TravelIndicator ResolutionDial TypeIncluded Contact Point*Standard requiredDescriptionModel
USS Improved Buttress2.950”.250”.001”0-25-0, BalancedTBRYesExternal Thread Height Gage for USS Improved Buttress, 0-25-0, T500C-USSTH-3000-USS
¾” TPF Buttress2.930”.250”.0005”0-25-0, BalancedT072YesExternal Thread Height Gage, 0-25-0, T072TH-3002B**
¾” TPF Buttress3.730”.500".0001”0-10-0, BalancedT072YesExternal Thread Height Gage, 0-10-0, .0001” Resolution Indicator, T072TH-3002B-1
¾” TPF Buttress2.930”5 mm.01 mm0-50-0, BalancedT072YesExternal Thread Height Gage, 0-50-0, Metric Indicator, T072TH-3002B-M**
1” TPF Buttress2.930”.250”.0005”0-25-0, BalancedT072YesExternal Thread Height Gage with Step Base, 0-25-0, T072TH-3003B
1” TPF Buttress3.730”.250”.0001”0-10-0, BalancedT072YesExternal Thread Height Gage with Step Base, 0-10-0, .0001” Resolution Indicator, T072TH-3003B-1
8 Round3.400”.185”.001”0-100 ContinuousT501NoExternal Thread Height Gage, 0-100, T501TH-3001R
8 Round4.25”.190”.0001”0-5-0, BalancedT501YesExternal Thread Height Gage, 0-5-0, .0001” Resolution Indicator, T501TH-3001R-1
8 Round3.400”.162”/4.1 mm.01 mm0-10-0, BalancedT501YesExternal Thread Height Gage, 0-10-0, Metric Indicator, T501TH-3001R-M
8 Round & 10 Round3.400”.162”.001”0-50-0, BalancedT501YesExternal Thread Height Gage, 0-50-0, T501TH-3002R
8 Round & 10 Round4.25”.500".0001”0-10-0, BalancedT501YesExternal Thread Height Gage, 0-10-0, .0001” Resolution Indicator, T501TH-3002R-1
8 Round & 10 Round3.400”5 mm.01 mm0-50-0, BalancedT501YesExternal Thread Height Gage, 0-50-0, Metric Indicator, T501TH-3002R-M
Rotary Shouldered Connections, Tool Joints2.930”.250”.0005” 0-25-0, BalancedT072YesExternal Thread Height Gage, 0-25-0, T072TH-3000-RSC
Rotary Shouldered Connections, Tool Joints3.730”.250".0001”0-25-0, Balanced
T072YesExternal Thread Height Gage, 0-25-0, .0001” Resolution Indicator, T072TH-3000-RSC-1
Rotary Shouldered Connections, Tool Joints2.930”5 mm.01 mm0-50-0, BalancedT072YesExternal Thread Height Gage, 0-50-0, Metric Indicator, T072TH-3000-RSC-M
UN/UNJ/UNR, ACME, Stub ACME, Stub ACME Modified 1, Stub ACME Modified 2, Metric M & MJ, 7° X 45° Buttress, Line Pipe, and General Purpose Pipe Threads2.930".196”.001”0-100, ContinuousT500CNoExternal Thread Height Gage, 0-100, T500CTH-3001V
UN/UNJ/UNR, ACME, Stub ACME, Stub ACME Modified 1, Stub ACME Modified 2, Metric M & MJ, 7° X 45° Buttress, Line Pipe, and General Purpose Pipe Threads3.730”.500".0001”0-10-0, BalancedT500CYesExternal Thread Height Gage, 0-10-0, .0001” Resolution Indicator, T500CTH-3001V-1
UN/UNJ/UNR, ACME, Stub ACME, Stub ACME Modified 1, Stub ACME Modified 2, Metric M & MJ, 7° X 45° Buttress, Line Pipe, and General Purpose Pipe Threads2.930”.250".0005”0-10-0, BalancedT500CYesExternal Thread Height Gage, 0-10-0, .0005” Resolution Indicator, T500CTH-3001V-5
UN/UNJ/UNR, ACME, Stub ACME, Stub ACME Modified 1, Stub ACME Modified 2, Metric M & MJ, 7° X 45° Buttress, Line Pipe, and General Purpose Pipe Threads2.930”5 mm.01 mm0-10-0, BalancedT500CYesExternal Thread Height Gage, 0-10-0, Metric Indicator, T500CTH-3001V-M
Line Pipe, Tool Joints2.930”.250”.001”0-50-0, BalancedT500CYesExternal Thread Height Gage, 0-50-0, T500CTH-3002V
Line Pipe, Tool Joints3.730”.500".0001”0-10-0, BalancedT500CYesExternal Thread Height Gage, 0-50-0, .0001” Resolution Indicator, T500CTH-3002V-1
*TH-3002B and TH-3002B-M also serve as an external thread addendum (shave) gage, THS-1014S standard required

 

Internal Thread Height Gages

TH3006oncasing

Gagemaker also manufactures several models of internal thread height gages. Please specify the type of thread when ordering.

Some gages require a setting standard, see below for standards.

Contact point listed in description (e.g. T072) is included, but may specify other.

Internal Thread Height Gages
ConnectionMin. BoreIndicator TravelIndicator ResolutionDial TypeIncluded Contact Point*Standard requiredDescriptionModel
Line Pipe1.50”.250”.0005”0-25-0, BalancedT500CYesInternal Thread Height Gage, 0-25-0, T500CTH-3004
Line Pipe1.50”.250”.0001”0-25-0, BalancedT500CYesInternal Thread Height Gage, 0-25-0, .0001” Indicator Resolution, T500CTH-3004-1
Line Pipe1.50"/38.1 mm10 mm.01 mm0-50-0, BalancedT500CYesInternal Thread Height Gage, 0-50-0, Metric IndicatorTH-3004-M
8 Round & 10 Round1.50”.105”.0005”0-25-0, BalancedT502 and T503YesInternal Thread Height Gage, 0-25-0, T502 and T503TH-3006
8 Round & 10 Round1.50”.105”.0001”0-25-0, BalancedT502 and T503YesInternal Thread Height Gage, 0-25-0, .0001” Indicator Resolution, T502 and T503TH-3006-1
8 Round & 10 Round1.50”/38.1 mm10 mm.01 mm0-50-0, BalancedT502 and T503YesInternal Thread Height Gage, 0-50-0, Metric IndicatorTH-3006-M
8 Round & 10 Round1.575”.500”.0005”0-25-0, BalancedT502 and T503YesInternal Thread Height Gage, 0-25-0, T502 and T503TH-3008
¾” TPF Buttress1.50”.250”.0005”0-25-0, BalancedT072YesInternal Thread Height Gage, 0-25-0, T072TH-3009
Rotary Shouldered Connections1.50”.250”.0005”0-25-0, BalancedT072YesInternal Thread Height, 0-25-0, 1" Base Length, T072TH-3009-RSC
Rotary Shouldered Connections1.50”.250”.0001”0-10-0, BalancedT072YesInternal Thread Height, 0-25-0, .0001” Indicator Resolution, 1" Base Length, T072TH-3009-RSC-1
UN/UNJ/UNR, ACME, Stub ACME, Stub ACME Modified 1, Stub ACME Modified 2, Metric M & MJ, 7° X 45° Buttress, Line Pipe, and General Purpose Pipe Threads1.50”.250”.001”0-100 ContinuousT500CNoInternal Thread Height, 0-100, 1" Base Length (TPD), T500TH-3010
USS Improved Buttress1.50”.250”.001”0-25-0, BalancedT500C-USSYesInternal Thread Height, T500C-USSTH-3010-USS
¾” - 2" NPT, AMT.750".250”.005”0-25-0, BalancedT500CYesInternal Thread Height Gage, 0-25-0TH-3012
¾” - 2" NPT, AMT.750".500”.0001”0-10-0, BalancedT500CYesInternal Thread Height Gage, 0-25-0, .0001” Indicator ResolutionTH-3012-1

 

 

Thread Addendum Gages

Thread addendum is now a mandated inspection according to the API 5B Specification 16th Ed. Gagemaker also manufactures several models of thread addendum (a.k.a. shave) gages. Please specify the type of thread when ordering.

Addendum gages require setting with a particular standard. Standard sold separately.

Contact point (T072) is included with every TA-3002. For 10 Round threads, a different contact point (T057) is required and sold separately.

Thread-Addendum-Newsletter

Thread Addendum Gages
ConnectionMin. BoreIndicator TravelIndicator ResolutionDial TypeRequired Contact Point*Standard requiredDescriptionModel
8 Round2.930”.250”.0005”0-25-0, BalancedT072TAS-1014External Addendum Gage, 0-25-0, T072TA-3002
10 Round2.930”.250”.0005”0-25-0, BalancedT057TAS-1014External Addendum Gage, 0-25-0TA-3002
8 Round3.730”.500".0001”0-10-0, BalancedT072TAS-1014External Addendum Gage, 0-10-0, .0001” Resolution Indicator, T072TA-3002-1
10 Round3.730”.500".0001”0-10-0, BalancedT057TAS-1014External Addendum Gage, 0-10-0, .0001” Resolution IndicatorTA-3002-1
8 Round2.930”5 mm.01 mm0-50-0, BalancedT072TAS-1014External Addendum Gage, 0-50-0, Metric Indicator, T072TA-3002-M
10 Round2.930”5 mm.01 mm0-50-0, BalancedT057TAS-1014External Addendum Gage, 0-50-0, Metric IndicatorTA-3002-M
8 Round0.750".250”.0005”0-25-0, Balanced T072TAS-1014Internal Addendum Gage, 0-25-0, T072TA-3012
10 Round0.750".250”.0005”0-25-0, Balanced T057TAS-1014Internal Addendum Gage, 0-25-0TA-3012
*T072 is included with every TA-3002. A T057 for 10 Round is sold separately.

Thread Height Standards

TCHeightStandard

Gagemaker manufactures precision setting standards for presetting thread height gages. Please specify type of thread when ordering.

Custom or special standards are available, please contact customer service for more information.

Rotary Shouldered Connection Standards
Connection TypeConnection SizeTPITPFThread Form Required Contact PointModel
Hughes External Flush2⅜” - 2⅞” 62”V-0.032T034THS-10322-RS
API Numbered Connections #23 - #5042”V-0.038RT072THS-10382-RS
Double Streamline3½” - 5½”42”V-0.038RT072THS-10382-RS
API Full Hole4”42”V-0.038RT072THS-10382-RS
Hughes Slim Hole2⅜” - 4½” 42”V-0.038RT072THS-10382-RS
Hughes External Flush3½” - 4½”42”V-0.038RT072THS-10382-RS
Hughes Xtra Hole2⅞” - 5”42”V-0.038RT072THS-10382-RS
Internal Flush2⅜” - 6⅝” 42”V-0.038RT072THS-10382-RS
Wide Open2⅜” - 4½” 42”V-0.038RT072THS-10382-RS
API Numbered Connections #56 - #8443”V-0.038RT072THS-10383-RS
API Regular2⅜” - 4½”53”V-0.040T034THS-10403-RS
API Full Hole2⅞”, 3½”, & 4½”53”V-0.040T034THS-10403-RS
API Regular6⅝” 42”V-0.050T044THS-10502-RS
API Full Hole5½” & 6⅝” 42”V-0.050T044THS-10502-RS
API Regular5½”, 7⅝”, & 8⅝” 43”V-0.050T044THS-10503-RS
API Numbered Connections#10, #12, #13, #1661.5”V-0.055T072THS-10551.5-RS
API Regular (Macaroni Tubing)1” - 1.5”61.5”V-0.055T072THS-10551.5-RS
American Open Hole2⅜” - 4½” 41.5”V-0.076T044THS-10761.5-RS
P.A.C. Connections 2⅜” - 3½” 41.5”V-0.076T044THS-10761.5-RS
Hughes H-902⅜” - 3½” 3.52”90-V-0.050T072THS-10H90-2
Hughes H-907” - 8⅝”3.53”90-V-0.050T072THS-10H90-3
Hughes Slimline H-902⅜” - 3½” 31”90-V-0.084T072THS-SL-H90
Tubing & Casing Standards
ConnectionTPFDescriptionThread Form Model
8 Round & 10 Round¾”Thread Height Standard, 8 & 10 RoundEUE, NUE, LTC, STCTHS-1014
8 & 11½ Pitch "V" Threads¾”Thread Height Standard, 8 & 11½ Pitch "V" ThreadsLine Pipe & NPTTHS-1015
13⅜” & Smaller Buttress¾”Thread Height Standard, ¾” ButtressButtressTHS-1017
16” & Larger Buttress1”Thread Height Standard, 1” ButtressButtressTHS-1018
USS Improved Buttress¾”Thread Height Standard, USS ButtressUSS Improved ButtressTHS-10409

 

 

Thread Height Contact Points

Gagemaker thread height gages use a variety of contact points, from our traditional threaded shank ball contact point to specialized points for a particular thread form. The ball contact points are carbide balls precision ground to strict industry standards.

Thread Height Contact Points
ConnectionThread FormBall DiameterDescriptionGageModel
ButtressButtress (¾” & 1”).072”Thread height contact point for buttress threadsTH-3002B, TH-3002B-1, TH-3002B-M, TH-3003B, TH-3003B-1, TH-3009T072
8 RoundLTC, STC, EUE, & NUE.072”Thread shave/addendum contact point for 8 RoundTH-3002B, TH-3002B-1, TH-3002B-MT072
10 RoundEUE & NUE.057”Thread shave/addendum contact point for 10 RoundTH-3002B, TH-3002B-1, TH-3002B-MT057
Rotary Shouldered ConnectionsV-0.038R.072”.072” Thread height contact point for Rotary Shouldered ConnectionsTH-3000-RSC, TH-3000-RSC-1, TH-3000-RSC-MTH-3009RSCT072
Rotary Shouldered ConnectionsV-0.055.072”.072” Thread height contact point for Rotary Shouldered ConnectionsTH-3000RSC, TH-3009RSCT072
Rotary Shouldered ConnectionsV-0.050.044”.044” Thread height contact point for Rotary Shouldered ConnectionsTH-3000RSC, TH-3009RSCT044
Rotary Shouldered ConnectionsV-0.076.072”.072” Thread height contact point for Rotary Shouldered ConnectionsTH-3000RSC, TH-3009RSCT072
Rotary Shouldered ConnectionsV-0.032.034”.034” Thread height contact point for Rotary Shouldered ConnectionsTH-3000RSC, TH-3009RSCT034
Rotary Shouldered ConnectionsV-0.040.034”.034” Thread height contact point for Rotary Shouldered ConnectionsTH-3000RSC, TH-3009RSCT034
ANSI Threads, ASME Threads, ISO Threads, "V" Threads, Line Pipe, and General Purpose Pipe ThreadsUN/UNJ/UNR, ACME, Stub ACME, Stub ACME Modified 1, Stub ACME Modified 2, Metric M & MJ, 7° X 45° Buttress, "V" Threads, Line Pipe, and General Purpose Pipe Threads-50° cone contact pointTH-3001V, TH-3001V-1, TH-3001V-5, TH-3002V, TH-3002V-1, and TH-3004T500C
USS Improved ButtressUSS Improved Buttress-Narrow cone contact point for USS Improved ButtressTH-3000-USSTBR
8 Round & 10 RoundLTC, STC, EUE, & NUE-50° cone contact point, "V" Threads for TH-3001R, TH-3001R-1, TH-3002R, and TH-3002R-1TH-3001R, TH-3001R-1, TH-3002R, TH-3002R-1T501
8 Round & 10 RoundLTC, STC, EUE, & NUE-Self-centering sleeve for T501 & T503 contact pointsTH-3001R, TH-3001R-1, TH-3002R, TH-3002R-1, TH-3006T502
8 Round, 10 Round, "V" ThreadsLTC, STC, EUE, NUE, & Line Pipe-50° cone contact point, "V" Threads for TH-3006TH-3006T503
Extreme LineExtreme Line-.063 R Extreme Line contact pointSpecialE-Line