Standard: ASME - ANSI B2.2


This standard is available for individual purchase.

or unlock this standard with a subscription to IHS Standards Expert

IHS Standards Expert subscription, simplifies and expedites the process for finding and managing standards by giving you access to standards from over 370 standards developing organizations (SDOs).

  • Maximize product development and R&D with direct access to over 1.6 million standards
  • Discover new markets: Identify unmet needs and discover next-generation technologies
  • Improve quality by leveraging consistent standards to meet customer and market requirements
  • Minimize risk: Mitigate liability and better understand compliance regulations
  • Boost efficiency: Speed up research, capture and reuse expertise
For additional product information, visit the IHS Standards Expert page.

For more information or a custom quote, visit the IHS Contact Us page for regional contact information.


Dryseol Pipe Threads

Dryseal pipe threads differ from the USA (American) pipe thread, as their purpose is to seal pressuretight joints without the necessity of using sealing compounds. To accomplish this some modification of thread form, greater accuracy in manufacture, and more analytical gaging are required. The roots of both the external and internal threads are truncated slightly more than the crests, Le. roots have wider flats than crests, so that metal-to-metal contact occurs at the crests and roots coincident with or prior to flank contact, see Fig. 1. Thus as the threads are assembled by wrenching, the roots of the threads crush the sharper crests of the mating threads. This sealing action at both the major and minor diameters tends to prevent spiral leakage and makes the joints pressuretight without the necessity of using sealing compounds, provided that the mating threads are in accordance with standard specifications and tolerances and are not damaged by galling in assembly. These ends are accomplished by the use of properly designed threading tools. Also, it is necessary that both external and internal threads have full thread height for the entire effective length of the thread makeup. That is, the diameters of the hole before tapping and of the external thread blank correspond to the maximum material limits.

However, where not functionally objectionable, the use of a compatible lubricant or sealant may be used to minimize the possibility of galling. This is desirable in assembling Dryseal pipe threads in refrigeration and other systems to effect a pressuretight seal.1

1The refrigeration industry has generally accepted the use of a sealant to obtain an absolute pressuretight joint, when assembling taper pipe threads made according to USAS B2.1 or USAS B2.2.

Organization: ASME International
Document Number: ansi b2.2
Publish Date: 1968-01-01
Page Count: 63
Change Type: ERTA
Available Languages: EN
DOD Adopted: NO
ANSI Approved: NO
Most Recent Revision: YES
Current Version: NO
Status: Inactive