Pumper Thread Charts If a thread gauge and caliper are not available, and a sample cannot be sent, the following method can be used to obtain the correct outside diameter and pitch of the thread needed.
	Cut a strip of paper about 1"(25mm) wide, long enough to wrap tightly around the circumference of the male thread and overlap at the ends. With a pin, pierce through both layers of the paper (fig.1). Press your thumb firmly against the thread hard enough to make a thread impression on the strip (fig. 2). Remove the strip and circle the pin holes on the strip with a pencil (fig. 3). Divide the distance between the pin holes by 3.1416. The result is the ODM (outside diameter of the male).
It is important that both the ODM and threads per inch (pitch) of the male part are given when ordering. Always include the paper strip with your correspondence. If not specified, "V" sharp thread will be furnished.

 

COMMONLY USED THREADS

	National Standard NH		Straight Iron Pipe NPSH		New York Corp NYC		New York City FD NYCFD		Eastern Hose		New York Corp NYC		Pacific Coast PCT		Chicago Hose		Chicago Fire Dept CFD		British Standard Pipe Thread BSP
Size	ODM	TPI	ODM	TPI	ODM	TPI	ODM	TPI	ODM	TPI	ODM	TPI	ODM	TPI	ODM	TPI	ODM	TPI	ODM	TPI
¼"	1.375	8	1.035	14	1.062	11.5					1.078	11	1.062	11	1.081	11.5
1"	1.375	8	1.295	11.5					1.660	8	1.422	11	1.312	11.5	1.295	11.5			1.309	11
1½"	1.990	9	1.878	11.5			2.093	11	2.100	8	2.125	11	2.100	11	1.946	11.5	1.933	11.5
2"	2.515	8	2.352	11.5			2.547	11	2.530	8	2.672	7.5	2.550	10	2.522	8			1.882	11
2½"	3.068	7.5	2.841	8			3	8	3.030	8	3.000	8	3.035	7.5	3.043	7	2.990	7.5	2.960	11
3"	3.623	6	3.470	8					3.630	8
3½"	4.243	6	3.970	8					4.070	8							4.052	8	4.125	3
4"	5.010	4	4.470	8					4.610	8			4.828	6			5.011	4	4.625	3
4½"	5.760	4	4.970	8					5.800	4							5.750	4	5.125	3
5"	6.260	4															6.057	4	5.625	3
6"	7.025	4																	6.625	3

NOTE: NPT thread not available on female swivels.

 

SUCTION HOSE THREADS

	American Lafrance			Mack Truck			Seagrave FWD			Hale Fire Pump			Waterous			Ward Lafrance			Maxim
Size	ODM	TPI	Shake	ODM	TPI	Shake	ODM	TPI	Shake	ODM	TPI	Shake	ODM	TPI	Shake	ODM	TPI	Shake	ODM	TPI	Shake
4"	5.085	4	0.050	5.760	4	0.060	4.955	4	0.060	5.010	4	0.050	5.010	4	0.060	5.010	4	0.050	5.000	4	0.050
4½"	5.760	4	0.050	5.760	4	0.050				5.760	4	0.050	5.760	4	0.060	5.760	4	0.050	5.750	4	0.050
5"	6.150	4	0.050	6.205	4	0.050	6.055	4	0.050	6.260	4	0.050	6.260	4	0.060	6.260	4	0.050	6.250	4	0.050
6"	7.000	4	0.050	6.955	4	0.050	7.055	4	0.050	7.025	4	0.050	7.261	4	0.060	7.025	4	0.050	7.000	4	0.050

 

CANADIAN SUCTION HOSE THREADS

	Lafrance			Mack			King Seagrave			American Marsh			Piere Thibault
Size	ODM	TPI	Shake	ODM	TPI	Shake	ODM	TPI	Shake	ODM	TPI	Shake	ODM	TPI	Shake
4"	5.085	4	0.050	4.999	4	0.050	4.938	4	0.050	4.995	4	0.050	4.660	5	0.045
4½"	5.750	4	0.050	5.760	4	0.060	5.750	4	0.050	5.750	4	0.050	5.720	4	0.060
5"	6.150	4	0.050	6.230	4	0.050	6.073	4	0.050	6.062	4	0.050	6.240	4	0.035
6"	7.000	4	0.050	6.980	4	0.050	7.073	4	0.050	6.980	4	0.050	6.940	4	0.074

 

CANADIAN STANDARD 2½" HOSE THREADS

		ODM	TPI
AMA	Alberta Mutual Aid	2.990	8
BCT	British Columbia	3.000	8
CSA	Canadian Standards Assoc.--Ontario	3.125	5
QST	Province of Quebec Std.	3.031	7
WCT	Western Canada Fire Underwriters	3.250	6
	Nova Scotia--Zone 1	3.234	5
QMT	Quebec/Montreal Combination	3.031	7

ODM = Outside diameter of male.
TPI = Thread per inch.

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