Pipe Tap Nomenclature

Tue, 31 Aug 2021 09:35:49 GMT

go to see Welding Machine for Pipe Tap Nomenclature

I am looking at two 1" pipe taps, both are from Vermont American, one slightly longer than the other, each is labeled as followsonger tap:1 NPT HSS 11 1/2GM2FSlightly shorter tap:1 NPT HSS 11 1/2GM2DI understand most of this nomenclature, (1", National Pipe Taper, High Speed Steel, 11 1/2 tpi) but I don't know what the "G" represents, and I don't know what the difference is between the M2F and the M2D other than the latter is a bit shorter. I am sure there is something more technical than this.The Vermont American web site knowledgebase and tap information pages offered no explanations, and the site does not offer an email address or inquiry form.So.. I was hoping someone here could shed some light on these designations.Thanks!MondoMember, AWSLincoln ProMIG 140Lincoln AC TombstoneCraftsman Lathe 12 x 24 c1935Atlas MFC Horizontal MillCraftsman Commercial Lathe 12 x 36 c1970- - - I'll just keep on keepin' on.
Reply:I think this PDF will explain it to you.I believe the M2F is or fuel, and the M2G is for gas.http://www.iceweb.com.au/Tubings/Gla...ech%20Info.pdf.No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
ReplySW: Thank you for the reference, My search did not find that one.  This helps, but does not explain the markings directly.  There is still something missing....  the markings on the taps are as shown:GM2FandGM2DG for gas, on both?   Then what is designated by the M2F and M2D ?Can I safely assume the F is for Dryseal (Fuel) as suggested in the Glastonbury document? But then what about the D?  And why the M2 that appears in both?I will try to make some sense of it.  Maybe I will need to write a letter to VA in Lyndonville.- MondoPS:  Vermont American no longer maintains offices in Lyndonville VT.  Now owned by Robert Bosch, GmbH in Germany, the US office is in Illinois.   mLast edited by Mondo; 01-09-2013 at 10:41 AM.Reason: add post script.Member, AWSLincoln ProMIG 140Lincoln AC TombstoneCraftsman Lathe 12 x 24 c1935Atlas MFC Horizontal MillCraftsman Commercial Lathe 12 x 36 c1970- - - I'll just keep on keepin' on.
Reply:Give 'em a call.I use dryseal medium hook pipe taps but I still apply some type od sealant, usually anerobic.  One issue with a dryseal fit is sometimes the male-female threads will sieze.  sealant eliminates that if, you ever have to take it apart.Not fond of Vermont-American tooling.  Not a quality or at least not the quality of Cleveland Twist but cheaper for sure.Machinerys Handbook will give you all the nomenclature breakdowns.  It's nice to have a copy on the shelf and it don't have to be a current one.  The current ones have everything up to date concerning new advancements but an older one will have what you require as well.
Replyure speculation, but here goes.  The dryseal and other types of threads should be part of the NPT designation, (NPTF)so anyway, G = Ground, not too many other ways to make a tap, (a good one anyway)M2 = type of steel used (a HSS tool steel)D or F = who knows, but maybe the length of the tap!also here is the link to contact VAhttp://www.vermontamerican.com/Compa...mation/EmailUsExperience is something you get right after you need it
Reply:Originally Posted by Fred sPure speculation, but here goes.  The dryseal and other types of threads should be part of the NPT designation, (NPTF)so anyway, G = Ground, not too many other ways to make a tap, (a good one anyway)M2 = type of steel used (a HSS tool steel)D or F = who knows, but maybe the length of the tap!also here is the link to contact VAhttp://www.vermontamerican.com/Compa...mation/EmailUs
Reply:FredS:Thanks for the link to the VA email form.  I sent them essentially the same inquiry.Where did you find the form?- MondoMember, AWSLincoln ProMIG 140Lincoln AC TombstoneCraftsman Lathe 12 x 24 c1935Atlas MFC Horizontal MillCraftsman Commercial Lathe 12 x 36 c1970- - - I'll just keep on keepin' on.
Reply:clear at the bottom of the page, tiny little fontExperience is something you get right after you need it
Reply:Originally Posted by Fred sclear at the bottom of the page, tiny little font
Reply:Two emails to VA and this is their final answer:"Our technicians do not have any information on this. They suggested that they may have been old manufacturer date codes. The way date codes have been marked has changed several times over the years as the companies have changed hands."- MondoMember, AWSLincoln ProMIG 140Lincoln AC TombstoneCraftsman Lathe 12 x 24 c1935Atlas MFC Horizontal MillCraftsman Commercial Lathe 12 x 36 c1970- - - I'll just keep on keepin' on.
Reply:if the primary difference is the style on the end it could mean drill and flute.  any chance that corresponds to the implied function?