Caterpillar H90C Hydraulic Hammer Specs and Applications

[MikePhua]

Definitions and Key Terms

• Hydraulic Hammer / Breaker: An attachment driven by hydraulic fluid power (from an excavator, backhoe, etc.) used for demolition, breaking rock, concrete, or pavement.
  
• Blows per Minute (bpm): Number of impact strikes the hammer delivers in a minute. A higher rate increases productivity, depending on the material.
  
• Energy Class: The force of each blow—often in foot-pounds (ft-lb) or joules (J). Higher energy per blow means deeper or more aggressive breaking.
  
• Operating Pressure: The hydraulic pressure required for the hammer to perform its rated energy and frequency. Measured in psi (pounds per square inch) and/or bar.
  
• Oil Flow (gpm/Lpm): The volume of hydraulic fluid the carrier machine must supply to drive the hammer. Larger flow means more power, assuming the hammer can use it efficiently.
  
• Recommended Carrier Weight: The weight range of machines (excavators, backhoes) that can safely and effectively carry the hammer, matching hydraulic capability and structural strength.
  

History and Product Context
Caterpillar Inc. has produced hydraulic hammers (“breakers”) for many decades, tailoring models to different machine sizes and applications such as mining, road construction, demolition, and quarrying. The “H” series lines (H45, H50, H63, H70, H90C, H100, etc.) are among their mid-to-large size hydraulic hammers, with “silenced” variants (denoted “s”) for noise-sensitive projects. The H90C is designed for carriers in approximately the 6- to 12-tonne range in metric, or about 13,200-26,400 lb machines.
Key Specifications of the CAT H90C Hammer
Below are the typical specifications for the H90C / H90C S model:

• Recommended Carrier Weight: 13,200-26,400 lb (≈ 6,000-12,000 kg)
  
• Working Weight (hammer + standard tool + mounting bracket): about 1,206-1,320 lb (≈ 547-600 kg) depending on variant (silenced vs non-silenced)
  
• Impact Frequency: 500-1,450 bpm (blows per minute)
  
• Energy per Blow (Energy Class): about 1,000 ft-lb (≈ 1,356 J)
  
• Hydraulic Oil Flow Required: 60-150 L/min (≈ 16-39 gpm)
  
• Operating Pressure: around 1,958 psi (≈ 135 bar)
  
• Dimensions / Tool Interface:
  • Tool diameter: ~84 mm (≈ 3.3 in)
    
  • Typical hammer tool length: ~417 mm (≈ 16.4 in) for standard tools with H90C
    
  • Hammer housing height (non-silenced and silenced) and side plate lengths vary; flat-top and pin-on mounting versions exist. For example, flat-top H90C is ~20.1-20.5 in length of side plates, pin-on version ~29.4 in.
    
• Noise / Sound Power Level: The silenced variant reduces noise; sound power levels are reported around 133 dB(A) / 127 dB(A) depending on variant and test conditions.
  

Applications and Best Use Scenarios

• Breaking concrete, road surfaces, pavements.
  
• Trenching through rock for utilities.
  
• Demolition of concrete and weaker rock formations.
  
• Quarry oversize breaking (i.e. splitting large sections).
  
• Often used with excavators in the 7- to 12-ton machine class.
  

Design Features and Durability Enhancements

• The hammer includes full-length side plates to protect the internal “power cell” and front head from damage.
  
• Lower tool bushings are field-replaceable; they have grease retention grooves and dust seals to keep contaminants out. Improves lifespan under abrasive conditions.
  
• There is a high pressure accumulator mounted at the back of hammer to protect against hydraulic pressure spikes, preserving both hammer and carrier pump integrity.
  
• Silenced versions (“s” suffix) reduce sound level, making them more suitable in residential or regulatory noise-sensitive environments.
  

Maintenance and Service Considerations

• Replace the lower tool bushings when wear becomes excessive; grease and dust seals must be maintained regularly.
  
• Inspect tool retention pins and front-head alignment: misalignment increases fatigue and wear.
  
• Maintain hydraulic oil cleanliness: particle contamination damages internal seals, pistons, and bushings.
  
• Check operating pressure and oil flow: low flow or pressure reduces impact energy and can cause overheating or inefficient performance.
  

Real Cases and Anecdotes
A contractor in the Pacific Northwest needed a hammer for demolition in a suburban area. They chose the H90C silenced model because noise limits were strict. After installing it on an 11-ton excavator, they found that even with reinforced concrete walls, the productivity rate matched estimates—about 50-60 cubic yards per shift, similar to unsilenced models but without noise complaints.
Another user in quarry work reported that the standard tool life with H90C (rock chisels in abrasive granite) was about 500‐600 hours; with regular inspection of bushings and ensuring clean hydraulic oil, they extended this to nearly 750 hours.
Suggestions and Solutions

• When using the H90C in highly abrasive material (e.g. quartzite, hard granite), consider using hardened or rehardening tool bits, change bushings and seals more often.
  
• If carrier machine has less hydraulic flow available (below 60 L/min), performance will degrade; consider upgrading hydraulic hoses or pump (if possible) or selecting a smaller hammer.
  
• For transporting the hammer or installing, ensure that mounting brackets (flat-top vs pin-on) are compatible; pin-on adds length and weight but may ease tool change.
  

Conclusion
The Caterpillar H90C / H90C S hydraulic hammer is a mid-to-upper class breaker suited for excavators in the ~6-12 tonne category. It delivers around 1,000 ft-lb (≈ 1,356 J) energy per blow, with 500-1,450 blows per minute, operating at pressures of ~1,958 psi and requiring hydraulic flows of ~60-150 L/min. It balances punch and durability with features like silencing, protective housings, field replaceable bushings, and provisions against pressure spikes. For many demolition, road, and quarry applications it remains a dependable workhorse so long as proper maintenance and matching to carrier capabilities are observed.