When you look at the numbers of the YO18 hand‑held rock drill, you can roughly guess what kind of tool it is. This is not a toy drill. With a weight of 18 kg and an overall length of about 550 mm, plus a 58 mm cylinder diameter and 45 mm piston stroke, the YO18 is a serious Pneumatic jack hammer for people who need real impact energy in hard rock, but still want the flexibility of a hand held jack hammer.
The basic data looks like this:
Weight: 18 kg
Overall length: 550 mm
Cylinder diameter: 58 mm
Piston stroke: 45 mm
Inner diameter of air pipe: 19 mm
Inner diameter of water pipe: 8 mm
Bit shank: 22 × 108 mm
Service air pressure: 3.9–5.9 × 10⁵ Pa (4–6 kgf/cm²)
Service water pressure: 3.9–5.9 × 10⁵ Pa (4–6 kgf/cm²)
Storage (oil) capacity: 200 ml
From general rock drill knowledge, anything under about 30 kg is normally treated as a hand‑held rock drill. At 18 kg, the YO18 sits in the middle of that range: clearly stronger than 6–12 kg tools, but still portable enough for one person to handle as a hand held jack hammer.
How The YO18 Pneumatic Jack Hammer Actually Works
If we combine the above parameters with the usual working principle of pneumatic rock drills, the picture becomes clearer.
Inside the YO18:
Compressed air at about 0.39–0.59 MPa (the 3.9–5.9 × 10⁵ Pa in the data) drives a piston in a 58 mm cylinder.
The piston moves back and forth with a 45 mm stroke, hitting the tail of a 22 × 108 mm drill steel at high frequency.
Each blow sends an impact wave down the steel to the bit, which cuts into the rock and forms a small pit.
Between blows, the drill steel rotates a small angle, so the next impact falls on fresh rock instead of the previous pit.
Broken rock is flushed out by a mix of compressed air and water that comes through the 19 mm air pipe and 8 mm water pipe.
This is exactly the impact‑plus‑rotation method described in rock drill theory: impact breaks the rock, rotation changes the contact point, and air/water carry the cuttings out. The relatively large 58 mm cylinder and 45 mm stroke tell you the YO18 has higher single‑blow energy than small 6–8 kg drills, which is what you want if you’re drilling harder rock or slightly larger holes.
The data also shows that both service air pressure and service water pressure are in the 3.9–5.9 × 10⁵ Pa (4–6 kgf/cm²) range, which is consistent with general recommendations that pneumatic rock drills work best around 0.45–0.55 MPa, and should not be used below 0.4 MPa if you care about efficiency.
Typical Applications Suggested By The Data
Just from the parameters, we can already see where a YO18 jack hammer makes sense:
Tunneling and mining headings
With 18 kg weight and a 58 mm cylinder, the YO18 has enough strength for face drilling in underground headings, where you need reliable impact and wet drilling. The 22 × 108 mm shank matches common chisel and cross bits used for blast holes.Quarry bench and secondary blasting
Compared with very light hand drills, the extra weight helps control recoil when you drill into hard rock benches or break oversize boulders.Slope support and anchor holes
The combination of air + water (both at 3.9–5.9 × 10⁵ Pa) and an 8 mm water line makes it suitable for environments where dust must be controlled, like slope stabilization or underground support.
In short, this Pneumatic jack hammer is for users who feel that 6–10 kg tools are not strong enough, but a full air‑leg machine is too heavy and complicated for their job.
Questions Buyers Usually Ask About The YO18 Hand Held Jack Hammer
Below are a few questions that usually come up in practice, answered using the YO18 data and general rock drill principles.
1. Is 18 kg still reasonable for hand‑held work?
According to standard rock drill classification, tools under about 30 kg are still considered hand‑held. At 18 kg, the YO18 is heavier than a Y8 or Y12 style drill, but still clearly in the hand held jack hammer range.
What the 18 kg really gives you:
Better stability on the rock surface
More usable impact energy from the 58 mm cylinder
Less “jumping” when the bit hits hard or uneven rock
If the job involves mainly horizontal or inclined holes (face drilling, benching), most operators will find 18 kg acceptable. For long periods of overhead drilling, a lighter jack hammer may be more comfortable, but you lose some of the power that the YO18 provides.
2. How big of a compressor do I need?
The data gives us service air pressure 3.9–5.9 × 10⁵ Pa (4–6 kgf/cm²) and an air hose inner diameter of 19 mm. The 19 mm hose alone tells you the YO18 wants more air than smaller drills that use 13 mm hoses.
From general experience with Pneumatic jack hammers:
The key is not just compressor pressure, but pressure at the drill while it is working.
With a 19 mm hose, pressure drop is smaller than with a thin hose, but you still need a compressor that can hold about 0.45–0.55 MPa at the YO18 under load.
For one YO18 Pneumatic jack hammer, many sites use compressors around 1.5–2.5 m³/min at 0.5–0.7 MPa. If you plan to run two or three YO18 units at the same time, you simply scale up so that each machine can still get close to the 3.9–5.9 × 10⁵ Pa working range.
3. How should I set air and water pressure?
The product data is quite clear:
Service air pressure: 3.9–5.9 × 10⁵ Pa (4–6 kgf/cm²)
Service water pressure: 3.9–5.9 × 10⁵ Pa (4–6 kgf/cm²)
Based on general rock drill practice:
Try to keep air pressure around 0.45–0.55 MPa at the machine; don’t let it drop below 0.4 MPa, otherwise drilling speed and flushing get noticeably worse.
Water pressure can be in the same range, but it should not be much higher than the air pressure. If water pressure is too high compared to air, water can force its way into parts of the jack hammer where it shouldn’t be, wash away oil, and increase wear.
So, a practical rule for the YO18: air and water both inside the 4–6 kgf/cm² zone, with air usually slightly higher or at least not lower.
4. What kind of bits and steels can I use?
The YO18 uses:
22 × 108 mm shank specification
This is one of the most common standards for hand held jack hammers and rock drills. It means:
You can choose from a wide variety of chisel bits, cross bits, button bits, etc., as long as the shank is 22 × 108 mm.
It’s easy to find compatible bits and rods in most mining and quarry markets.
Given the 58 mm cylinder and 45 mm stroke, the YO18 has enough impact to drive typical 22 × 108 mm bits in medium and hard rock without feeling under‑powered, provided you keep the air pressure where it should be.
5. What is the 200 ml storage capacity for?
The storage capacity 200 ml in the data is for oil. The YO18 has internal space or an attached oiler that can hold about 200 ml of lubricating oil.
From rock drill maintenance experience:
This does not mean you can forget about lubrication. It simply reduces how often you must refill.
You should always use clean rock drill oil, never dirty waste oil. Dirty oil brings abrasive particles into the Pneumatic jack hammer, which shortens the life of the cylinder and valve parts.
During operation, check that there is a thin oil film at the shank and a light oil mist in the exhaust. That’s a simple way to verify the oil feed is working.
The combination of a 200 ml oil reservoir and regular checks is usually enough to keep the YO18 well lubricated during a working shift.
6. What daily maintenance should I plan for?
The YO18 does not require anything very special; it follows typical Pneumatic jack hammer care:
Before starting:
Blow out the 19 mm air hose to remove water and dust.
Check oil level in the 200 ml storage.
Start‑up:
Open air slowly, let the drill run at low speed for a short time, listen for abnormal sounds.
During work:
Watch hose connections, nuts and bolts; vibration can gradually loosen them.
At the end of the shift:
Shut off the water first.
Let the YO18 run on air only for a little while to blow out remaining water inside.
If the machine will sit idle for longer, add some oil and store it in a dry place.
These small steps, combined with correct air and water pressure, are usually enough to keep a YO18 hand held jack hammer in good condition.
A Short Wrap‑Up
If we put all the numbers and principles together, the YO18 hand‑held rock drill is basically a strong, wet‑drilling Pneumatic jack hammer for serious rock work:
18 kg weight and 550 mm length – still portable, but clearly more robust than small 6–10 kg drills.
58 mm cylinder, 45 mm stroke, 19 mm air pipe – built to hit harder and take more air.
22 × 108 mm shank – uses standard hand‑held drill steels and bits.
3.9–5.9 × 10⁵ Pa air and water pressure, 8 mm water pipe – suited to wet drilling with good dust control.
200 ml oil storage – supports longer running with proper lubrication.
For tunneling, small mining, quarry benching or slope support in medium‑hard to hard rock, the YO18 is the kind of hand held jack hammer that makes sense when you want more power than a light tool, but still want the flexibility and simplicity of a Pneumatic jack hammer that one person can handle.