
The Merit 991A2 Flat Hard Rock Chisel is engineered for high-impact performance in demanding demolition, mining, and construction environments. Fully compatible with Rammer hydraulic breakers, this tool delivers consistent energy transfer, reduced wear, and extended service life even under the toughest working conditions.
Built for Hard Rock Performance
Manufactured from premium alloy steel and subjected to advanced heat treatment processes, the 991A2 chisel is designed to withstand extreme stress and abrasion. Its flat chisel profile ensures efficient surface breaking and controlled material removal, making it highly effective in applications involving granite, basalt, and reinforced concrete.
Precision Manufacturing by Merit
Every Merit chisel is produced under strict quality control standards to guarantee dimensional accuracy and material consistency. The 991A2 model is manufactured to OEM-equivalent specifications, ensuring seamless compatibility with Rammer breaker models and reliable field performance.
Technical Specifications
- Diameter: 165.5 mm
- Length: 1,400 mm
- Weight: 218 kg
Key Advantages
- High-grade alloy steel for maximum durability
- Optimized heat treatment for longer service life
- Full compatibility with Rammer hydraulic breakers
- Superior resistance against impact and wear
- Designed to minimize downtime and maintenance costs
Applications
- Hard rock quarrying and mining
- Heavy-duty demolition projects
- Road breaking and trenching operations
- Foundation and tunneling work
Complete 4099 Rammer Hydraulic Breaker Parts List
This comprehensive parts list includes all essential components required for maintenance, repair, and overhaul of 4099 series hydraulic breakers.
Housing Unit – Heavy Duty
- Housing: 168083
- Pad: 104068
- Buffer: 104137
- Plug: 158147, 160576, 400491, 953291
- Seal: 160558
- Wear Parts: 166176
- Shield Plate: 105780
- Wear Plate: 162525
- Label Set: 170456
- Lifting Eye (M36): 901464
- Hex Screws & Fasteners: 90520, 901465, 90521, 90519
Housing Unit – Hard Rock
- Housing: 168080
- Wear Plates: 160797, 160796
- Wear Parts: 166177
Housing Unit – Primary Breaking
- Housing: 168080
- Buffer: 172579
- Buffer Holder: 172287
- Plates & Screws: 172155, 172370, 172371
- Wear Parts: 166177
Hydraulic System Components
Accumulator System
- Accumulator Assembly: 160006
- Membrane: 172307
- Accumulator Body: 160018, 160019
- Sealing Components: O-rings, seals, USIT rings
Main Valve System
- Main Valve Assembly: 169987
- Spools & Bushings: 169988, 169989, 110986, 110781
- Cover & Seals Included
Ram Valve
- Ram Valve Assembly: 171029
- Internal Components: Spool, Spring, Seal, Shim
Pressure Control Valve
- Valve Assembly: 161980
- Components: Spool, Guide, Spring, Shim Plates
Idle / Stroke Selector Valve
- Valve Assembly: 163445
- Complete internal configuration included
Structural & Core Components
Tie Rod Assembly
- Tie Rod: 163002
- Vibration Dampening & Locking Parts Included
Body Components
- Cylinder: 160002
- Piston: 160003
- Valve Body: 162999
- Seal Carrier & Breather System
Front Head Assembly
- Front Head: 173681
- Tool Retention System Included
Tool Bushings
- Upper & Lower Tool Bushings: 160009, 160008
Hydraulic Breaker Working Tools
- Chisel (991) – General demolition
- Moil Point (993) – Precision work
- Blunt Tool (994) – Secondary breaking
- Pyramid Tool (993K3) – Specialized applications
- Hard Rock Chisel (991A2) – Extreme conditions
- Limestone Chisel (991F3) – Softer materials
- Super Blunt (994T2) – High-impact operations
Seal Kits & Service Kits
- Complete Seal Set: 165464
- Service Kit (Basic): K14099
- Heavy Duty Kit: K2A4099
- Hard Rock Kit: K2B4099
- Primary Breaking Kit: K2D4099
All kits are designed to ensure fast servicing, reduced downtime, and reliable sealing performance.
Greasing Equipment & Accessories
- Greasing Block Kit: 168833
- Hose Assembly: 168842
- Greasing Device RG542: 953345
- Grease Cartridge: 951370








