Straight Adapter Female DKO x Male O-Ring
This is where Helesul DKO hydraulic adapters (Double Cone O-ring) stand out as the strategic choice for manufacturers and operators who demand unwavering reliability, delivering a robust solution built on versatility, superior sealing, and global compatibility.
- Technical Details
- Applications
- Dimensions Table (O-Ring)
- Size Chart (DKO)
- Standards met: DIN 2353 (L, S) / ISO 8434-1;
- External diameters: 6 mm – 42 mm (metric tubes);
- Maximum operating pressure: 420 bar (6,000 PSI);
- Operating temperature: -40°C to +120°C;
- Body material: carbon steel;
- Surface finish: trivalent zinc plating;
- O-ring: NBR 90 Shore A;
- Certification: ISO 9001.
Harvesters and Agricultural Sprayers
In articulated boom circuits and hydraulic controls exposed to constant vibration and uneven terrain, DKO hydraulic adapters maintain stable sealing, mitigate soil contamination from oil leaks, and reduce corrective interventions. The dual sealing system withstands rapid cycles and pressure spikes typical of field maneuvering, preserving overall system efficiency.
Tractors and Soil Preparation Implements
In reversible plow cylinders, leveling discs, and subsoilers, the 24° O-ring profile delivers a robust connection against impacts and cyclic loads, ensuring precise actuation response. Torque repeatability minimizes loosening and sustains productivity throughout extended working shifts.
Dump Trucks and Road Vehicles
In tipper body and platform lifting operations, DKO connections contribute to safe and continuous operation, maintaining full sealing throughout repetitive cycles. High torque resistance helps preserve assembly integrity after periodic maintenance and inspections across road fleets.
Mowers and Side Sweepers
Exposed to dust, debris, and thermal variations, articulated arm systems benefit from the resilient O-ring and conical seat sealing, reducing micro-leaks and maintaining stable pressure. This extends maintenance intervals and optimizes equipment availability.
Presses and Compactors
In machines operating under constant high pressure, the dual sealing system prevents progressive fluid losses that degrade force and speed. The result is a more consistent cycle, lower oil consumption, and improved output per hour — especially in continuous industrial operations.
|
|
Nominal Size |
Bore (D) [mm] |
|
5/16"-24 |
7,9 |
|
|
3/8"-24 |
9,5 |
|
|
7/16"-24 |
11,1 |
|
|
1/2"-20 |
12,7 |
|
|
9/16"-18 |
14,3 |
|
|
3/4"-16 |
19,0 |
|
|
7/8"-14 |
22,2 |
|
|
1.1/16"-12 |
27,0 |
|
|
1.3/16"-12 |
30,2 |
|
|
1.5/16"-12 |
33,4 |
|
|
1.5/8"-12 |
41,3 |
![]() |
Nominal Sizer |
Tube [mm] |
External Thread (d) [mm] |
Internal Thread (D) [mm] |
|
|
|
Light Series |
Heavy Series |
|
|
|
|
M12x1,5 |
6 |
- |
12 |
10,4 |
|
|
M14x1,5 |
8 |
6 |
14 |
12,4 |
|
|
M16x1,5 |
10 |
8 |
16 |
14,4 |
|
|
M18x1,5 |
12 |
10 |
18 |
16,4 |
|
|
M20x1,5 |
- |
12 |
20 |
18,4 |
|
|
M22x1,5 |
15 |
14 |
22 |
20,4 |
|
|
M24x1,5 |
- |
16 |
24 |
22,4 |
|
|
M26x1,5 |
18 |
- |
26 |
24,4 |
|
|
M30x2 |
22 |
20 |
30 |
27,8 |
|
|
M36x2 |
28 |
25 |
36 |
33,8 |
|
|
M42x2 |
- |
30 |
42 |
39,8 |
|
|
M45x2 |
35 |
- |
45 |
42,8 |
|
|
M52x2 |
45 |
38 |
52 |
49,8 |
|
In general, yes, thanks to the metric and UNF options and the use of adapters when necessary. Check the thread/port pair and the machine pattern.
Fewer microleaks, faster assembly and less rework, which translates into more available machines and lower fluid consumption throughout the life cycle.
DKO (Double Cone O-ring) adapters use a double O-ring sealing system, while traditional JICs have only one sealing cone. The DKO system reduces leaks by up to 98% and offers a useful life 3 times longer, with tolerance to multiple assembly and disassembly without loss of efficiency.
Under normal conditions, no. The O-ring compensates for microsettlements. Use a torque wrench when assembling and follow the torque table by gauge. Frequent retightening may damage the O-ring.
Use PTFE tape if the connection will be retightened periodically. Prefer anaerobic sealant for permanent sealing and greater vibration resistance.
In agricultural hydraulic circuits, sealing failures can halt a harvester mid-harvest and generate high maintenance costs. The dual O-ring sealing system helps eliminate leaks even under intense vibration and pressure spikes, reducing unplanned downtime and fluid losses by up to 95% when installed per specifications.
The self-centering 24° cone speeds up assembly by up to 40% compared to conventional connections, minimizing rework and improving torque repeatability.
Helesul DKO hydraulic adapters (Double Cone O-ring) are designed for high-reliability sealing in high-pressure hydraulic systems, combining a self-centering 24° cone and O-ring for consistent performance in agricultural machinery and road applications.
With robust construction, they reduce leaks, simplify assembly, and boost equipment uptime even under vibration, intense cycles, and harsh environments.
All Helesul hydraulic adapters are manufactured to ISO, SAE, and DIN standards, ensuring interchangeability, safety, and predictable field performance.


