Pneumatic and hydraulic rock bolting machines, while both serving the core function of rock support operations—such as drilling, bolt installation, and grout mixing—differ significantly due to their drive mechanisms: pneumatic machines rely on compressed air, whereas hydraulic machines use hydraulic oil. This fundamental difference leads to notable distinctions in performance, applicable scenarios, and practical roles, primarily in the following aspects:

   I. Core Functional Differences

   1. Power Output and Operating Capability

  ① Pneumatic Rock Bolting Machine:

   Driven by compressed air, its power output (thrust and torque) is limited by air pressure (typically 0.5–0.7 MPa), resulting in medium-level overall power.

   Drilling Capability: Suitable for medium-soft rock (uniaxial compressive strength ≤ 60 MPa) and shallow holes (hole depth ≤ 3 meters). Efficiency drops significantly in hard rock or deeper drilling, with a higher risk of drill jamming.

   Installation Force: Thrust and torque are less stable, making it difficult to apply high prestress for bolts such as high-strength threaded bolts. More suitable for installing standard, non-prestressed bolts.

  ② Hydraulic Rock Bolting Machine:

   Powered by high-pressure oil from a hydraulic pump (typically 10–20 MPa), offering strong and controllable power output with much higher thrust and torque than pneumatic models.

   Drilling Capability: Efficient in hard rock (uniaxial compressive strength ≥ 80 MPa) and deep hole operations (depth 3–10 meters). Drilling force is stable, less prone to jamming, and offers better accuracy (verticality and hole consistency).

   Installation Force: Thrust and torque can be precisely controlled via hydraulic valves, enabling the stable application of high prestress (up to several tons), ideal for demanding support scenarios such as initial tunnel support or high slope reinforcement.

   2. Operating Efficiency and Stability

   ① Pneumatic Rock Bolting Machine:

   Performance is affected by compressor flow and air pressure fluctuations (e.g., pressure drops in long pipelines). Drilling speed and grout mixing (rotation speed) can be unstable. It typically takes 5–10 minutes to complete one bolt installation.

  ② Hydraulic Rock Bolting Machine:

   The hydraulic system provides stable pressure and flow, with 30%–50% faster drilling speeds in hard rock compared to pneumatic models. Mixing is more uniform, ensuring full grout blending (fewer bubbles and stronger adhesion). A single bolt installation usually takes 3–6 minutes, making it ideal for large-scale, high-strength support projects.

   3. Operational Flexibility and Adaptability

   ① Pneumatic Rock Bolting Machine:

   Simple structure (mainly pneumatic motor, reducer, drill rod), lightweight (15–30 kg), easy to operate handheld or with a light frame. Well-suited for confined spaces such as underground coal mine roadways or small-section tunnels.

  ② Hydraulic Rock Bolting Machine:

   Requires a hydraulic station or onboard hydraulic system. Heavier main unit (typically 50–200 kg or more), usually needs rails or robotic arms for feed control. Less flexible, better for open spaces like open-pit slopes or large-section tunnels.

   II. Practical Differences in Application Scenarios and Value

   1. Suitable Environments

   ① Pneumatic Rock Bolting Machine:

   Ideal Scenarios: Explosive or flammable environments (e.g., coal mines, gas tunnels), since compressed air operation creates no sparks and is naturally explosion-proof. Also suitable for narrow, low-clearance spaces (e.g., roadways < 2.5 meters in height), due to light weight and ease of operation.

   Limitations: Requires an air compressor and pipelines, making it impractical in areas with no or unstable air supply (e.g., remote slopes).

   ② Hydraulic Rock Bolting Machine:

   Ideal Scenarios: Projects requiring hard rock drilling, deep holes, and high prestress (e.g., subway tunnels, hydropower slopes, metal mines). Ensures support strength and efficiency. Independent of air sources, suitable for field or large-scale operations.

   Limitations: Potential for hydraulic oil leakage (environmental pollution), and hydraulic components (pumps, valves) are sensitive to dust and impurities. Additional protection needed in dusty environments like dry mines.

  2. Safety and Maintenance Costs

   ① Pneumatic Rock Bolting Machine:

   Safety: No oil leakage risk. Components (pneumatic motor, air lines) are wear-resistant. Failures usually result from air supply interruption, without risk of high-pressure oil spray. Ideal for clean environments (e.g., slopes near food production facilities).

   Maintenance: Simple structure with few wear parts (mainly drill bits and seals), low maintenance cost, and easy for workers to learn and operate.

   ② Hydraulic Rock Bolting Machine:

   Safety: Requires measures to prevent oil leakage (which could pollute soil/water). High-pressure hoses may rupture, potentially causing injury. Regular inspection of seals and lines is necessary.

   Maintenance: Precision components like hydraulic pumps and valves require regular oil changes and filtration. Maintenance costs are higher, and operators need technical skills (e.g., hydraulic system tuning).

   Pneumatic rock bolting machines are characterized by their lightweight design, explosion-proof operation, and low cost, making them suitable for simple support tasks in medium-soft rock, narrow spaces, or flammable/explosive environments.

   Hydraulic rock bolting machines excel in high power, efficiency, and stability, making them ideal for complex projects involving hard rock, deep holes, and high prestress requirements.

   The choice between them should be based on a comprehensive assessment of rock hardness, working space, environmental safety, and required support strength. Ultimately, it is a trade-off between flexibility and lightness versus power and efficiency.