Page 385 - ParkerBrassCatalog2010

Parker Hannifn Corporation
Parker Brass Products Division
Otsego, Michigan
Catalog 3501E General Technical
N5
N
Thread Specifcations
Dryseal Pipe Threads
All dryseal pipe threads are manufactured in accordance with the
American National Standards Institute (ANSI) B1.20.3 specifcation and
designed to seal pressure tight joints. The threads may incorporate
the NPTF (National Standard Pipe Taper Fuel and Oil), PTF-SAE
Short, PTF-SPL Short or PTF-SPL Extra Short form. Dryseal threads
are used on brass products found within this catalog. Use of a thread
sealant is recommended.
Non-Dryseal Pipe Threads
All non-dryseal pipe threads are manufactured in accordance with the
American National Standards Institute (ANSI) B1.20.1 specifcation.
These tapered pipe threads are used on our carbon and stainless steel
products. Use of a thread sealant is recommended.
Nickel Plating
Nickel plating is available for all standard product fttings. Plating will
increase male pitch diameters and decrease female pitch diameters
of threads. This will affect the assembly characteristics on standard
products.
Nickel plating provides a corrosion resistant coating which is desirable
in many applications. Electrolytic nickel plating is the standard plating
supplied unless otherwise specifed. This will provide a uniform cover-
age of external surfaces; however, internal surfaces may be uncoated.
Unifed Threads
Non-Dryseal Pipe Thread
Flanks are in contact with possible clearance between the
roots and crests.Will not prevent spiral leakage
Dryseal Pipe Thread
Metal to metal contact. Crests of thread are crushed by the
roots when wrench-tightened to form seal.
BS2779 British Standard Pipe Thread for
Non-Pressure Tight Joints
Thread tolerances allow for possible clearance between
threads.Will not prevent leakage paths.
BS21 British Standard Pipe Thread for Pres-
sure Tight Joints
Metal to metal contact provides seal as tapered thread is
wrench-tightened.
All threads in the columns headed “Straight Thread” found within this
catalog are manufactured in accordance with the American National
Standards Institute (ANSI) B1.1 specifcation.
British Standard Pipe Threads BSPT and BSPP
Pressure Tight
The British pipe threaded products found within this catalog intended
for use where pressure tight joints are made on the threads are
manufactured in accordance with British Standard (BS) 21 and
International Standards Organization (ISO) 7-1. The threads are
designated as follows:
Rp: Internal parallel
Rc: Internal taper
Rs: Special external parallel
R: External taper
Use of a thread sealant is recommended with the R series thread. An
elastomeric peripheral seal should be used with the Rs thread.
Non-Pressure Tight
All British Standard parallel pipe threads manufactured in this catalog
according to BS2779 and ISO 228-1 are intended for use where
pressure tight joints are not made on the threads. An elastomeric
peripheral seal should be used. These threads are designated as
follows:
G: Internal Thread
GA, External thread, tight tolerance classifcation
GB, External thread, general purpose and assumed if no
classifcation designation is given