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HK Series (Brass)
ISO 7241-1 B Interchange
Fluid transfer & Hydraulic application

Danfoss Hansen HK brass is a general purpose industrial
interchange coupling available in valved or non-valved
designs, offered in brass for excelllent corrosion resistance
in rugged applications where stainless steel is
unacceptable. The HK Series features a ball latch
mechanism with automatic self-sealing poppet valves
Brass_HK

Product Features

• Meets dimensional requirements to ISO standard
7241-1 Series B
• The coupling that sets the industry standard
• Self-sealing poppet valve design provides excellent high and low
pressure sealing
• Standard seal material: Nitrile (NBR)
• Seal options available in PTFE, Neoprene, FKM, EPDM, and Kalrez®
• Standard body material: Zinc trivalent plated steel with stainless
steel springs, balls and retaining rings.
• PTFE back up rings in sockets (females

European Pressure Equipment Directive

Couplings with nominal diameters up to and including 25 mm
are designed and manufactured under Article 4.3 of the Eu
ropean Pressure Equipment Directive 2014/68/EU. Couplings
with nominal diameters greater than 25 mm are designed and
manufactured in accordance with stipulations of Module A of the
European Pressure Equipment Directive 2014/68/EU. They should
not be used to convey unstable gases.
Group 1 = Hazardous media / Group 2 = Other media

Physical Characteristics
Series Specifications Table
Series Body Size (in) ISO Size (mm) Nominal Flow Diameter (mm) Max. Pressure
Non-Hazardous (bar)
Max. Pressure
Non-Hazardous (psi)
Max. Pressure
Hazardous (bar)
Max. Pressure
Hazardous (psi)
Rated Flow (lpm) Rated Flow (gpm) Air Inclusion (cc max.) Fluid Loss (cc max.)
1HK 5 4.4 207 3,000 207 3,000 3 0.8 0.6 0.5
2HK ¼ 6.3 5.9 186 2,700 186 2,700 12 3 1.2 0.9
3HK 10 7.8 152 2,200 152 2,200 23 6 2.9 2.1
4HK ½ 12.5 10 155 2,250 155 2,250 45 12 3.6 3.5
6HK ¾ 20 17 138 2,000 138 2,000 100 26 11.5 9.3
8HK 1 25 19.6 103 1,500 103 1,500 189 50 18.0 16.9
10HK 1¼** 26.7 83 1,200 37 537 288 76 48.0 48.0
12HK 40 35.1 104 1,500 29 421 375 99 91.3 91.3
20HK 50 46 49 700 21 305 757 200 209.9 209.9

* For questions related to vacuum please contact Danfoss.
** No ISO Standard available for the 10HK

Applications & Markets
• Agriculture
• Hydraulic Tool
• General Industry
• Construction
• Fluid Transfer
• Transportation
• Military
• Law Enforcement/Rescue
• Chemical
• Oil and Gas
• Consumer Products
• HVAC
• Food and Beverage
• Trucks
• Aerospace
• Medical

Flow Data

flowchart brass hk

Seal Elastomer Data*

Seal Elastomer** Max. Operation Temperature Range
Nitrile (NBR) -40°C to +121°C / -40°F to +250°F
Neoprene -54°C to +100°C / -65°F to +212°F
EPDM -54°C to +149°C / -65°F to +300°F
FKM -29°C to +204°C / -15°F to +400°F

* For reference only, based on Danfoss recommended temperatures.
** For seals not listed, contact Danfoss.

HK Series (Steel)
ISO 7241-1 B Interchange

Sockets/Female

Hansen 1HK-8HK Socket
HK1-8 Series Specifications Table
Part Number Body Size (in) ISO Size (mm) Thread Size (NPTF) Thread Size (BSPP) Fig. A (in) B (in) Across Flats (in) A (mm) B (mm) Across Flats (mm)
B1H11 5 ⅛-27 1 1.91 0.98 0.56 48.5 24.9 14.2
B2H16 ¼ 6.3 ¼-18 1 2.26 1.14 0.75 57.4 29.0 19.1
B2H16BS ¼ 6.3 ¼-19 1 2.31 1.14 0.75 58.7 29.0 19.1
B3H21 10 ⅜-18 1 2.56 1.42 0.88 65.0 36.1 22.4
B3H21BS 10 ⅜-19 1 2.56 1.42 0.88 65.0 36.1 22.4
B4HP26 ½ 12.5 ½-14 1 2.96 1.86 1.13 75.2 47.2 28.7
B4HP26BS ½ 12.5 ½-14 1 2.96 1.86 1.13 75.2 47.2 28.7
B6HP31 ¾ 20 ¾-14 1 3.48 2.22 1.31 88.4 56.4 33.3
B6HP31BS ¾ 20 ¾-14 1 3.48 2.22 1.31 88.4 56.4 33.3
B8HP36 1 25 1-11½ 1 4.13 2.61 1.75 104.9 66.3 44.5
B8HP36BS 1 25 1-11 1 4.13 2.61 1.75 104.9 66.3 44.5

A=Overall Length, B=Maximum Diameter
To obtain connected length of coupling, add dimensions A (Fig. 1) and E (Fig. 3) together

Sockets/Female

Hansen 10HK-20HK Socket
HK10/12/20 Series Specifications Table
Part Number Body Size (in) ISO Size (mm) Thread Size (NPTF) Thread Size (BSPP) Fig. A (in) B (in) Hex (in) A (mm) B (mm) Hex (mm)
B10H41* 1¼-11½ 2 4.51 2.73 2.38 114.6 69.3 60.5
B12H41 40 1¼-11½ 2 4.82 3.23 2.38 122.4 82.0 60.5
B12H41BS 40 1¼-11 2 4.82 3.23 2.38 122.4 82.0 60.5
B12H46 40 1½-11 2 4.82 3.23 2.38 122.4 82.0 60.5
B12H46BS 40 1½-11 2 4.82 3.23 2.38 122.4 82.0 60.5
B20H51 50 2-11½ 2 5.55 4.11 3.75 141.0 104.4 95.3
B20H51BS 50 2-11 2 5.55 4.11 3.75 141.0 104.4 95.3
B20H56 50 2½-8 2 6.14 4.11 3.75 156.0 104.4 95.3
B20H56BS 50 2½-11 2 6.14 4.11 3.75 156.0 104.4 95.3
B20H61 50 3-8 2 7.00 4.11 4.00 177.8 104.4 101.6
B20H61BS 50 3-11 2 7.00 4.11 4.00 177.8 104.4 101.6

Plugs/Male

Hansen 1HK-8HK Plug
HK1-8 Series Specifications Table
Part Number Body Size (in) ISO Size (mm) Thread Size (NPTF) Thread Size (BSPP) Fig. C (in) D (in) E (in) Hex (in) C (mm) D (mm) E (mm) Hex (mm)
B1K11 5 ⅛-27 3 1.26 0.65 0.44 0.56 32.0 16.5 11.2 14.2
B2K16 ¼ 6.3 ¼-18 3 1.52 0.87 0.56 0.75 38.6 22.1 14.2 19.1
B2K16BS ¼ 6.3 ¼-19 3 1.52 0.87 0.56 0.75 38.6 22.1 14.2 19.1
B3K21 10 ⅜-18 3 1.76 1.01 0.61 0.88 44.7 25.7 15.5 22.4
B3K21BS 10 ⅜-19 3 1.76 1.01 0.61 0.88 44.7 25.7 15.5 22.4
B4KP26 ½ 12.5 ½-14 3 2.03 1.30 0.76 1.13 51.6 33.0 19.3 28.7
B4KP26BS ½ 12.5 ½-14 3 2.03 1.30 0.76 1.13 51.6 33.0 19.3 28.7
B6KP31 ¾ 20 ¾-14 3 2.36 1.52 0.71 1.31 59.9 38.6 18.0 33.3
B6KP31BS ¾ 20 ¾-14 3 2.36 1.52 0.71 1.31 59.9 38.6 18.0 33.3
B8KP36 1 25 1-11½ 3 2.85 1.88 0.97 1.63 72.4 47.8 24.6 41.4
B8KP36BS 1 25 1-11 3 2.85 1.88 0.97 1.63 72.4 47.8 24.6 41.4

C=Overall Length, D=Maximum Diameter, E=Exposed Length when Connected
To obtain connected length of coupling, add dimensions A (Fig. 1) and E (Fig. 3) together

Plugs/Male

Hansen 10HK-20HK Plug
HK10/12/20 Series Specifications Table
Part Number Body Size (in) ISO Size (mm) Thread Size (NPTF) Thread Size (BSPP) Fig. C (in) D (in) E (in) Hex (in) C (mm) D (mm) E (mm) Hex (mm)
B10K41* 1¼-11½ 4 4.25 2.74 2.33 2.38 108.0 69.6 59.2 60.5
B12K41 40 1¼-11½ 4 4.76 2.74 2.67 2.38 120.9 69.6 67.8 60.5
B12K41BS 40 1¼-11 4 4.76 2.74 2.67 2.38 120.9 69.6 67.8 60.5
B12K46 40 1½-11 4 4.76 2.74 2.67 2.38 120.9 69.6 67.8 60.5
B12K46BS 40 1½-11 4 4.76 2.74 2.67 2.38 120.9 69.6 67.8 60.5
B20K51 50 2-11½ 4 5.49 4.33 2.97 3.75 139.4 110.0 75.4 95.3
B20K51BS 50 2-11 4 5.49 4.33 2.97 3.75 139.4 110.0 75.4 95.3
B20K56 50 2½-8 4 6.08 4.33 3.56 3.75 154.4 110.0 90.4 95.3
B20K56BS 50 2½-11 4 6.08 4.33 3.56 3.75 154.4 110.0 90.4 95.3
B20K61 50 3-8 4 6.94 4.62 4.42 4.00 176.3 117.3 112.3 101.6
B20K61BS 50 3-11 4 6.94 4.62 4.42 4.00 176.3 117.3 112.3 101.6

C=Overall Length, D=Maximum Diameter, E=Exposed Length when Connected
* ISO 7241-1 Series B does not include 1-¼ inch body size couplings; therefore, Series 10HK is not covered by this standard
To obtain connected length of coupling, add dimensions A (Fig. 2) and E (Fig. 4) together.

Dust Plugs and Dust Caps Accessories

Hansen 1HK-20HK Dustcaps
Coupling Series Dust Cap and Plug Part Numbers
Coupling Series Plug Dust Cap Part No. (Metal) Plug Dust Cap Part No. (Vinyl) Socket Dust Plug Part No. (Metal) Socket Dust Plug Part No. (Vinyl)
1HK XPDC1HK* XPPDC1HK SDC1HK* XPSDC1HK
2HK XPDC2HK* XPPDC2HK SDC2HK* XPSDC2HK
3HK XPDC3HK* XPPDC3HK SDC3HK* XPSDC3HK
4HK XPDC4HK** XPPDC4HK(RD)*** SDC4HK** XPSDC4HK(RD)***
6HK XPDC6HK** XPPDC6HK(RD)*** SDC6HK** XPSDC6HK(RD)***
8HK XPDC8HK** XPPDC8HK(RD)*** SDC8HK** XPSDC8HK(RD)***
12HK XPDC12HK** SDC12HK**
20HK XPDC20HK** SDC20HK**