DKO Blanking Plug Adapter
This is where Helesul DKO (Double Cone O-ring) hydraulic adapters stand out as the strategic choice for manufacturers and operators who refuse to compromise on reliability, delivering a robust solution built on versatility, superior sealing, and global compatibility.
- Technical Details
- Applications
- Dimensions Table (DKO)
- Compliant standards: DIN 2353 (L, S) / ISO 8434-1;
- Outside 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.
Agricultural harvesters and sprayers
In articulated boom circuits and hydraulic controls exposed to constant vibration and uneven terrain, DKO hydraulic adapters maintain a stable seal, mitigate soil contamination from oil leaks, and reduce the need for corrective maintenance. The dual seal withstands the rapid cycles and pressure spikes typical of field maneuvers, preserving overall system efficiency.
Tractors and tillage implements
In reversible plow cylinders, leveling harrows, and subsoilers, the 24° O-ring profile delivers a robust connection against impacts and cyclic loads, ensuring precise actuation responses. Torque repeatability minimizes the risk of loosening and sustains productivity during extended work shifts.
Dump trucks and highway vehicles
During the tipping of dump bodies and platforms, DKO connections contribute to a safe, continuous operation by maintaining a complete seal over repetitive cycles. Their high torque resistance helps preserve assembly integrity following periodic maintenance and inspections across highway fleets.
Boom mowers and side sweepers
Exposed to dust, debris, and extreme temperature fluctuations, articulated arm systems benefit from the resilient sealing of the O-ring and conical seat. This reduces micro-leaks and maintains stable pressure, ultimately extending maintenance intervals and optimizing equipment uptime.
Presses and compactors
In machines requiring constant high pressure, the dual sealing design prevents progressive fluid losses that can compromise force and speed. The result is a more consistent cycle, reduced oil consumption, and an improved hourly yield, particularly in continuous industrial operations.
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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.
Use PTFE tape if the connection will be retightened periodically. Prefer anaerobic sealant for permanent sealing and greater vibration resistance.
In agricultural hydraulic circuits, seal failures can halt a harvester during peak harvest season and drive up maintenance costs. The dual sealing system with O-ring effectively eliminates leaks even under intense vibration and pressure spikes, reducing unplanned downtime and fluid losses by up to 95% when installed per specifications.
The 24° self-centering cone speeds up assembly by up to 40% compared to conventional connections, minimizes rework, and enhances torque repeatability.
Helesul DKO hydraulic adapters (Double Cone O-ring) are engineered for high-reliability sealing in high-pressure hydraulic systems, combining a 24° self-centering cone and O-ring for consistent performance in agricultural machinery and road applications.
With robust construction, they cut 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.

