Leading Innovative Company "Maruzen”
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ROCK DRILL / DH204

DH204 Rock Drill: Built Sturdy, Drills with Confidence, Never Stops

1. Rugged Design
Proven in the toughest job sites, built to withstand demanding conditions.

2. Comprehensive After-Sales Support
Fast and reliable maintenance provided by our local distributor network.

3. Portability
Equipped with a Built-In-Compressor—no need for extra external equipment.
Ready to take to the site with minimal setup.

4. High Drilling Performance
4 drilling modes included as standard, adapting to a variety of rock conditions.

Application

  1. Pre-drilling for rock and concrete – for wedges, splitters, or blasting cartridges.
  2. Light crushing work – quick and efficient rock or concrete breaking on site.

Key Benefit: Enables fast, reliable preparation and simplified demolition with minimal equipment.

SPECIFICATIONS

Dimensions(mm) L555×W412×T110
Weight(kg) 20 (Without hoses)
Working Pressure(MPa) 8.8~11.8
Oil Flow(ℓ/min)
Blow Per Minute
Rotation Per Minute
(4 Modes)
20~25ℓ/min: 1000~1250bpm:0~500rpm
Shank Size 7/8″x4-1/4″ (22 x 108mm)
Coupling

3/8” Couplers
Built-in Compressor

Allowable Back Pressure(MPa) 2.5
Extension Hose Max1/2”×20
Recommended Hydraulic Oil ISO VG32(Standard) , ISO VG46 or equivalent.
Other External air supply available

 

[EXTERNAL AIR SUPPLY]

1. In case of deeper drilling(1.5m – 3.0m), air supply from outer source(air compressor)is more effective for drilling.

 (1) Recommended specifications of air source(air compressor)

Air Consumption 0.57㎥/min
Air Pressure 0.5MPa*1

 *1:When the air pressure of air source(compressor)is higher use regulator and adjust the air pressure.

 Be careful not to enter microscopic dust, sand or moisture into the machine through the air line.
 Otherwise, machine may be mechanically trouble.
 To supply clean and dry air into the machine, set-up of the air cleaner is recommendable.

 

(2) How to connect to external air supply
 Take of Plug(47)and connect air hose(IDΦ8.5). Connection of air hose is PT1/4.

 

PRODUCT MOVIES

HOW TO USE

Be sure that pressure and oil flow of the power source is suitable with specification above.

1. Before Start

(1) Open the drill stay and inset the rod.

(2) Close the drill stay. Make sure the rod(or other tools)is firmly locked.

(3) Make sure there are no dust, mud, or other foreigner substance on couplers when attaching extension hose and power source.(Lock couplers after connection.)

(4) Start the power source and allow hydraulic oil to flow into rock drill. 

 

2. Operation

(1) Drilling

Place the end of the rod on the place where you intend to drill, press down the rock drill gently, grip the control lever and start drilling.
   Rotation direction is clockwise when you look from the top of drill.
   (When rotating un-clockwise, please check the hoses are connected correctly.)

For preventing rock drill to bouncing around while operating, let the end of the rod closed to one of your feet and drill until the rock drill can be stably operated.

Adjust the rotation speed according to the type of the rock.

 

MODE Rotation per minutes Application
1 200~250rpm Hard Rock
2 250~350rpm Medium to Hard Rock
3 450~600rpm Soft Rock

* Rotation per minute above is rough standard. Please choose the mode depending on situation.

 

(2) Breaking

Use fluted moil point to have air escape.

Open drill stay and insert moil point.

Close the drill stay. Make sure the moil point has been fastened firmly.

Adjust the knob to “O” position.

 

3. After the Operation

(1) After the operation, stop the power source.

(2) Detach the connection hoses.

(3) Make sure all the couplers on standard hoses(attached to rock drill)and connection hoses are attached to each other to prevent dirt and etc. entering.

(4) Open the drill stay and remove moil point or tool.

(5) Clean all dirt, mud, and etc. on the rock drill.

MAINTENANCE

1. Please carry out the following processing before long-term storage.

 

(1) Connect DH204 with power source, and use moil point to push up the piston to the end.

(2) Apply anti-rust oil to piston from the shank end.

(3) Taking off (58) cleaner cover and (56) cleaner element and (57) cleaner sponge and apply anti-rust oil into the machine through the hole of cleaner case, and operate for about 1 minute in this condition. After that, put on cleaner cover and cleaner element as before.

CAUTION >
Failure to observe above (1) (2) (3) can cause rust inside the rock drill and lead to oil leak and anchoring.

(4) Clean air cleaner.

(5) Wipe the main body with cloth wetting with oil and clean it.
   Put on cover and store at the place where there are no humidity.

 

2. PERIODICAL INSPECTIONS

Ask your dealer for the periodical inspections.

Inspection Item Inspection Cycle
Nitrogen gas charge in accumulator 1 Year
Replacement of accumulator diaphragm 2 Years
Replacement of O-Ring
Replacement of U-Cup Packing
Replacement of compressor piston ring

* Accumulator Nitrogen gas pressure: 3.9MPa (40kgt/)

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