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Technical
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Technical
Thread Information
Abbreviation
System Name
Compatibility
Seal
Method
BSPP
British Standard Pipe Parallel
Male BSPP with Female BSPP
Female BSPP with Male BSPP
Female BSPP with Male BSPTr
Washer
Washer
Washer
BSPTr
British Standard Pipe Taper
Male BSPTr with Female BSPTr
Male BSPTr with Female BSPP
Female BSPTr with Male BSPTr
Female BSPTr not compatible with Male
BSPP
Thread
Washer
Thread
CHT
American Standard Fire Hose Thread
(1" National Hose Thread is Chemical
Hose Thread, also known as Booster
Hose Thread)
1" Male NH (NST) with 1" Female NH (NST)
1"Female NH (NST) with 1" Male NH (NST)
1" Thread is used on both ¾" hose and 1"
hose.
Not compatible with other systems
Washer
Washer
GHT
Garden Hose Thread
Male GHT with Female GHT
Female GHT with Male GHT
Thread is same for all size hose
Not compatible with other systems
Washer
Washer
IPS
Iron Pipe Straight Thread
Generic Name for Straight Pipe Thread
See NPSH for compatibility
Washer
IPT
Iron Pipe Thread
Generic Name for All Pipe Thread
More information required
NH
or
NST
American Standard Fire Hose Coupling
Thread
(National Hose thread also known as
National Standard Thread)
Male NH (NST) with Female NH (NST)
Female NH (NST) with Male NH (NST)
Not compatible with other systems
Thread pitch and diameters of fire threads
may vary according to local and municipal
regulations.
Washer
Washer
NPT
American Standard Taper Pipe Thread
(National Pipe Tapered)
Male NPT with Female NPT
Male NPT with Female NPTF
Male NPT with Female NPSM
Male NPT with Female NPSH
Female NPT with Male NPT
Female NPT with Male NPTF
Female NPT not compatible with Male NPSM
or Male NPSH
Thread
Thread
Washer
Washer
Thread
Thread
NPTF
American Standard Taper Pipe Fuel
Dryseal Thread (National Pipe Tapered
Fine)
Male NPTF with Female NPTF
Male NPTF with Female NPT
Male NPTF with Female NPSM
Male NPTF with Female NPSH
Female NPTF with Male NPTF
Female NPTF with Male NPT
Female NPTF with Male NPSM or NPSH
Note: NPTF with NPTF threads do not
require sealant for the initial use. After that,
sealant is required.
Thread
Thread
Washer
Washer
Thread
Thread
Not Compatible
NPSH
American Standard Straight Pipe for
Hose Couplings (National Pipe Straight
Hose)
Male NPSH with Female NPSH
Female NPSH with Male NPSH
Female NPSH with Male NPT
Female NPSH with Male NPTF
Female NPSH with Male NPSM
Washer
Washer
Washer
Washer
Washer
NPSM
American Standard Straight Mechanical
Joints (National Pipe Straight
Mechanical)
Male NPSM with Female NPSM
Male NPSM with Female NPSH
Female NPSM with Male NPSM
Female NPSM with Male NPT
Female NPSM with Male NPTF
Seal can be either
mechanical or washer.
Mating fittings must be
of same type.
SIPT
Straight Iron Pipe Thread
Generic name for Straight Pipe Thread
Washer
TIPT
Tapered Iron Pipe Thread
Generic name for Tapered Pipe Thread
Thread