FYOU PMEC Leading Solutions Crest Diameter and Ovality Inspection Gauges

Crest Diameter and Ovality Inspection

Crest Diameter Gages measure the internal and external pitch diameters of tapered threaded connections. Any slight variations in diameter or ovality are immediately detected with these precision gages granting you total control over your quality. These versatile gages easily adjust to measure thread diameters ranging from 1½” – 20”. The ability to inspect a range of diameters with one gage, eliminates the need for a room full of ring or plug gages.

External Crest Diameter Gage

Internal Crest Diameter Gage

Crest Diameter and Ovality Gages

CDG Series gages detects variations in crest diameter by the use of a gage shoe that rests on the crest of the threads. Variation in diameter is detected by the indicator readout. These gages must be set to a nominal size with one of a variety of setting standards. Refer to the standard chart that follows. All of these gages are API approved for use on tubing and casing.

P/N	Model	Description	Range
CDG-0512-Ext	ZJY5-W	External Crest Diameter Gage	External 1-1/2″~5-1/2″
CDG-0512-Int	ZJY5-N	Internal Crest Diameter Gage	Internal 1-1/2″~5-1/2″
CDG-0020-Ext	ZJY20-W	External Crest Diameter Gage	External 2-3/8″~20″
CDG-0020-Int	ZJY20-N	Internal Crest Diameter Gage	Internal 2-3/8″~20″

Rod Style Setting Standards for CDG Series Crest Diameter Gage

Rod style setting standards are designed to preset all models of the CDG Series gages for accurate inspection of API
threaded connections. Each set of standards consists of two precision ground rods that are ground to lengths in accordance
with API Specification 5B. All the standard styles and connections are available please refer as below chart.

Rod Style Setting Standards for CDG Series Crest Diameter Gage
Thread Type	Connections	PIN Standard Model	Box Standard Model
NUE	2⅜” NUE	CDGR-238NUE-P	CDGR-238NUE-B
	2⅞” NUE	CDGR-278NUE-P	CDGR-278NUE-B
	3½” NUE	CDGR-312NUE-P	CDGR-312NUE-B
	4” NUE	CDGR-4NUE-P	CDGR-4NUE-B
	4½” NUE	CDGR-412NUE-P	CDGR-412NUE-B
EUE	2⅜” EUE	CDGR-238EUE-P	CDGR-238EUE-B
	2⅞” EUE	CDGR-278EUE-P	CDGR-278EUE-B
	3½” EUE	CDGR-312EUE-P	CDGR-312EUE-B
	4” EUE	CDGR-4EUE-P	CDGR-4EUE-B
	4½” EUE	CDGR-412EUE-P	CDGR-412EUE-B


Thread Type	Connection	Pin Standard	Box Standard
Buttress	4½” Buttress	CDGR-412B-P	CDGR-412B-B
	5” Buttress	CDGR-5B-P	CDGR-5B-B
	5½” Buttress	CDGR-512B-P	CDGR-512B-B
	6⅝” Buttress	CDGR-658B-P	CDGR-658B-B
	7” Buttress	CDGR-7B-P	CDGR-7B-B
	7⅝” Buttress	CDGR-758B-P	CDGR-758B-B
	8⅝” Buttress	CDGR-858B-P	CDGR-858B-B
	9⅝” Buttress	CDGR-958B-P	CDGR-958B-B
	10¾” Buttress	CDGR-1034B-P	CDGR-1034B-B
	11¾” Buttress	CDGR-1134B-P	CDGR-1134B-B
	13⅜” Buttress	CDGR-1338B-P	CDGR-1338B-B
	16” Buttress	CDGR-16B-P	CDGR-16B-B
	18⅝” Buttress	CDGR-1858B-P	CDGR-1858B-B
	20” Buttress	CDGR-20B-P	CDGR-20B-B
LTC	4½” 8R LTC	CDGR-412L-P	CDGR-412L-B
	5” 8R LTC	CDGR-5L-P	CDGR-5L-B
	5½” 8R LTC	CDGR-512L-P	CDGR-512L-B
	6⅝” 8R LTC	CDGR-658L-P	CDGR-658L-B
	7” 8R LTC	CDGR-7L-P	CDGR-7L-B
	7⅝” 8R LTC	CDGR-758L-P	CDGR-758L-B
	8⅝” 8R LTC	CDGR-858L-P	CDGR-858L-B
	9⅝” 8R LTC	CDGR-958L-P	CDGR-958L-B>P110 or CDGR-958L-B<P110
	20” 8R LTC	CDGR-20L-P	CDGR-20L-B>JK55 or CDGR-20L-B<JK55


Thread Type	Connection	Pin Standard	Box Standard
STC	4½” – 9.50# 8R STC	CDGR-412S-9-P	CDGR-412S-9-B
	4½” – Other 8R STC	CDGR-412S-O-P	CDGR-412S-O-B
	5” – 11.50# 8R STC	CDGR-5S-11-P	CDGR-5S-11-B
	5” – Other 8R STC	CDGR-5S-O-P	CDGR-5S-O-B
	5½” 8R STC	CDGR-512S-P	CDGR-512S-B
	6⅝” 8R STC	CDGR-658S-P	CDGR-658S-B
	7” – 17.00# 8R STC	CDGR-7S-17-P	CDGR-7S-17-B
	7” – Other 8R STC	CDGR-7S-O-P	CDGR-7S-O-B
	7⅝” 8R STC	CDGR-758S-P	CDGR-758S-B
	8⅝” – 24.00# 8R STC	CDGR-858S-24-P	CDGR-858S-24-B
	8⅝” – Other 8R STC	CDGR-858S-O-P	CDGR-858S-O-B
	9⅝” 8R STC	CDGR-958S-P	CDGR-958S-B>P110 or 958S-B<P110
	10¾” – 32.75# 8R STC	CDGR-1034S-32-P	CDGR-1034S-32-B
	10¾” – Other 8R STC	CDGR-1034S-O-P	CDGR-1034S-O-B>P110 or CDGR-1034S-O-B<P110
	11¾” 8R STC	CDGR-1134S-P	CDGR-1134S-B>P110 or CDGR-1134S-B<P110
	13⅜” 8R STC	CDGR-1338S-P	1338S-B>P110 or 1338S-B<P110
	16” 8R STC	CDGR-16S-P	CDGR-16S-B
	18⅝” 8R STC	CDGR-1858S-P	CDGR-1858S-B
	20” 8R STC	CDGR-20S-P	CDGR-20S-B>JK55 or CDGR-20S-B<JK55

Frame Style Setting Standards for CDG Series Crest Diameter Gage

These frame style setting standards are designed to preset CDG Series gages for accurate inspection of API threaded connections. These standards consist of a rigid, non-adjustable steel block precision machined to proper size to tolerances of ±.0003”.

External Frame Style Setting Standards

Internal Frame Style Setting Standards

Frame Style Setting Standards for CDG Series Crest Diameter Gage
Thread Type	Connections	PIN Standard Model	Box Standard Model
NUE	2⅜” NUE	CDGF-238NUE-P	CDGF-238NUE-B
	2⅞” NUE	CDGF-278NUE-P	CDGF-278NUE-B
	3½” NUE	CDGF-312NUE-P	CDGF-312NUE-B
	4” NUE	CDGF-4NUE-P	CDGF-4NUE-B
	4½” NUE	CDGF-412NUE-P	CDGF-412NUE-B
EUE	2⅜” EUE	CDGF-238EUE-P	CDGF-238EUE-B
	2⅞” EUE	CDGF-278EUE-P	CDGF-278EUE-B
	3½” EUE	CDGF-312EUE-P	CDGF-312EUE-B
	4” EUE	CDGF-4EUE-P	CDGF-4EUE-B
	4½” EUE	CDGF-412EUE-P	CDGF-412EUE-B


Thread Type	Connection	Pin Standard	Box Standard
Buttress	4½” Buttress	CDGF-412B-P	CDGF-412B-B
	5” Buttress	CDGF-5B-P	CDGF-5B-B
	5½” Buttress	CDGF-512B-P	CDGF-512B-B
	6⅝” Buttress	CDGF-658B-P	CDGF-658B-B
	7” Buttress	CDGF-7B-P	CDGF-7B-B
	7⅝” Buttress	CDGF-758B-P	CDGF-758B-B
	8⅝” Buttress	CDGF-858B-P	CDGF-858B-B
	9⅝” Buttress	CDGF-958B-P	CDGF-958B-B
	10¾” Buttress	CDGF-1034B-P	CDGF-1034B-B
	11¾” Buttress	CDGF-1134B-P	CDGF-1134B-B
	13⅜” Buttress	CDGF-1338B-P	CDGF-1338B-B
	16” Buttress	CDGF-16B-P	CDGF-16B-B
	18⅝” Buttress	CDGF-1858B-P	CDGF-1858B-B
	20” Buttress	CDGF-20B-P	CDGF-20B-B
LTC	4½” 8R LTC	CDGF-412L-P	CDGF-412L-B
	5” 8R LTC	CDGF-5L-P	CDGF-5L-B
	5½” 8R LTC	CDGF-512L-P	CDGF-512L-B
	6⅝” 8R LTC	CDGF-658L-P	CDGF-658L-B
	7” 8R LTC	CDGF-7L-P	CDGF-7L-B
	7⅝” 8R LTC	CDGF-758L-P	CDGF-758L-B
	8⅝” 8R LTC	CDGF-858L-P	CDGF-858L-B
	9⅝” 8R LTC	CDGF-958L-P	CDGF-958L-B>P110 or CDGF-958L-B<P110
	20” 8R LTC	CDGF-20L-P	CDGF-20L-B>JK55 or CDGF-20L-B<JK55


Thread Type	Connection	Pin Standard	Box Standard
STC	4½” – 9.50# 8R STC	CDGF-412S-9-P	CDGF-412S-9-B
	4½” – Other 8R STC	CDGF-412S-O-P	CDGF-412S-O-B
	5” – 11.50# 8R STC	CDGF-5S-11-P	CDGF-5S-11-B
	5” – Other 8R STC	CDGF-5S-O-P	CDGF-5S-O-B
	5½” 8R STC	CDGF-512S-P	CDGF-512S-B
	6⅝” 8R STC	CDGF-658S-P	CDGF-658S-B
	7” – 17.00# 8R STC	CDGF-7S-17-P	CDGF-7S-17-B
	7” – Other 8R STC	CDGF-7S-O-P	CDGF-7S-O-B
	7⅝” 8R STC	CDGF-758S-P	CDGF-758S-B
	8⅝” – 24.00# 8R STC	CDGF-858S-24-P	CDGF-858S-24-B
	8⅝” – Other 8R STC	CDGF-858S-O-P	CDGF-858S-O-B
	9⅝” 8R STC	CDGF-958S-P	CDGF-958S-B>P110 or 958S-B<P110
	10¾” – 32.75# 8R STC	CDGF-1034S-32-P	CDGF-1034S-32-B
	10¾” – Other 8R STC	CDGF-1034S-O-P	CDGF-1034S-O-B>P110 or CDGF-1034S-O-B<P110
	11¾” 8R STC	CDGF-1134S-P	CDGF-1134S-B>P110 or CDGF-1134S-B<P110
	13⅜” 8R STC	CDGF-1338S-P	1338S-B>P110 or 1338S-B<P110
	16” 8R STC	CDGF-16S-P	CDGF-16S-B
	18⅝” 8R STC	CDGF-1858S-P	CDGF-1858S-B
	20” 8R STC	CDGF-20S-P	CDGF-20S-B>JK55 or CDGF-20S-B<JK55

For more information click the links below:

Disposition of Allowances, Tolerance and Crest Clearance for Acme Threads

ANSI and International Thread Series Designations

NON-UPSET (NUE) TUBING MASTER GAGES

UP SET (E.U.E) TUBING WORKING GAGES

NON-UPSET (N.U.E) TUBING WORKING GAUGES

Crest Diameter and Ovality Inspection

Crest Diameter and Ovality Inspection

Crest Diameter and Ovality Inspection

External Crest Diameter Gage

Internal Crest Diameter Gage

Rod Style Setting Standards for CDG Series Crest Diameter Gage

Frame Style Setting Standards for CDG Series Crest Diameter Gage

External Frame Style Setting Standards

Internal Frame Style Setting Standards

For more information click the links below:

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