April '21 Update: HART announces expanded manufacturing capacity for Carbon Steel Industrial Unions! Class 3000 and 6000.

How To Order


The charts below contain all the information necessary to place an order. Use the appropriate codes in the manner shown below.

Example: a Class 3000 Female Threaded 1" Union with Viton O-ring and 316 Stainless Steel Ends is coded as follows:

When a size reduction or change in material is needed, simply enter the Tailpiece code and then the Threadpiece code separated by a slash as shown below.

Example: A Dielectric Class 3000 Union with a Dielectric Coated A105 Carbon Steel Tailpiece that is 3/4" Female NPT, with a 304 Stainless 1/2" Male NPT Threadpiece, Teflon O-Ring, is coded as follows:

For more information, a quote, or to order, call 1-800-769-0503 or contact us at sales@hartindustries.com

O Orifice
D Dielectric (Insulating)
H Hammer Lug


Female NPT (FNPT) Class 3000 Pipe 31 31 0  (1/8")
1  (1/4")
2  (3/8")
3  (1/2")
4  (3/4")
5  (1")
6  (1 1/4")
7  (1 1/2")
8  (2")
9  (2 1/2")
10 (3")
11 (3 1/2")
12 (4")

V Viton® Florocarbon A (FKM-A)
E Ethylene Propylene (EPDM)
ES High-Temp Steam EPDM [up to 550*F max] (EPDM E0962)
T Teflon® Tetrafluroethylene (PTFE)
N Neoprene® Polychloroprene (CR)
K Kalrez® 4079 Perfluoroelastomer (FFKM)
HN Hydrogenated Nitrile (HNBR)
EP NSF-61 Approved Ethylene Propylene (EPDM)
G Metallic Spiral Wound Graphite Seal
I No O-Ring (Integral Seat "Ball and Cone")
Teflon®, Viton®, Kalrez® are
Registered Trademarks from DuPont
Male NPT (MNPT) Class 3000 Pipe 32 32
Socket Weld (SW) Class 3000 Pipe 33 33
Socket Weld (SW) Class 3000 Tube 34 34
Butt Weld (BW) Class 3000 Pipe 35 35
Sweat Copper Tube 36 36
Female NPT (FNPT) Class 6000 Pipe 61 61
Male NPT (MNPT) Class 6000 Pipe 62 62
Socket Weld (SW) Class 6000 Pipe 63 63
Socket Weld (SW) Class 6000 Tube 64 64
Butt Weld (BW) Class 6000 Pipe 65 65
A Aluminum
B Brass 464 or 360
CS A105 Carbon Steel
304 A182F304/304L Stainless Steel
304L A182F304/304L Stainless Steel
316 A182F316/316L Stainless Steel
316L A182F316/316L Stainless Steel
A20 Alloy 20 (Carpenter Steel C20)
73 70/30 Copper Nickel
91 90/10 Copper Nickel
H Hastelloy C-276
I Inconel 600
M Monel 400
T Titanium


MNPT: Place desired MNPT Wall Thickness in parentheses. Note: S40 Standard for Class 3000 and S80 Standard for Class 6000 unless otherwise specified.
Example: 6262-5-V-304(S160)
Butt Weld Pipe: Place desired BW Wall Thickness in parentheses. Note: S40 Standard for Class 3000 and S80 Standard for Class 6000 unless otherwise specified.
Example: 3535-5-V-304(S40)
Orifice Unions: Place desired drilled orifice bore in parentheses.
Example: O-3131-5-V-304(0.250")


BSPT-F BSPT (British Standard Pipe Taper) - Female, Rc
BSPT-M BSPT (British Standard Pipe Taper) - Male, R
BW TUBE Butt Weld with Tube O.D.
MALE PIPE END Male Pipe End (unthreaded) for socket welding.
ACME Nut ACME Thread Nut for specialty applications


Call to Order: 800-769-0503

18.06.2013. 09:11