Portable Skid-Mounted Mud Pumps for TBM Support: Keep the Boring Moving

Technical Specifications

Key Applications

Slurry Shield TBM Support

For slurry TBMs, our pump circulates bentonite suspension to the cutterhead, transports excavated soil to the separation plant, and maintains face pressure. We size the pump to match your slurry circuit flow and head requirements – typically 200–600 GPM at 50–150 PSI.

EPB Foam Injection

Earth Pressure Balance TBMs inject foam (a mixture of water, surfactant, and compressed air) to condition the soil. Our pump precisely meters foam solution into the injection line. The low-shear design prevents foam collapse – you get consistent conditioning, lower surfactant consumption, and fewer cutterhead clogging incidents.

Cutterhead Cooling & Flushing

Hard-rock TBMs generate enormous heat at the cutterhead. Our pump circulates cooling water or low-viscosity fluid through the cutterhead sprays, extending tool life and reducing disc cutter changeouts. The skid unit also serves as a high-pressure flushing source when you need to clear mud-packed cutters.

Grout & Backfill Pumping (Standby)

When the TBM’s primary grout pump fails, our mud pump can temporarily take over annular gap filling. Swap to a larger liner and you’re pumping cementitious grout at moderate pressures – enough to get you to the next maintenance bay.

Emergency Dewatering in the Tunnel

Tunnel inflows happen. Our pump doubles as a high-capacity dewatering unit – just change the fluid end configuration (we offer a quick-change kit). One machine for both TBM support and emergency water management.

Why Choose SJ Petroleum Machinery?

Built on Decades of Heavy-Duty Pumping Experience

SJ Petroleum Machinery is a wholly-owned subsidiary of Sinopec Oilfield Equipment Corporation – a company that has supplied high-pressure mud pumps to oilfields on six continents. That same engineering DNA goes into every TBM support pump. But we didn't just shrink an oilfield pump. We redesigned it for tunnel conditions: lower height, narrower width, simpler controls, and easier maintenance.

Tunneling-Specific Features at No Extra Cost

Standard on every TBM pump: external packing adjustment (no tools needed), color-coded lubrication points (grease every 8 hours), a drip pan with drain port (keeps the tunnel floor clean), and lifting eyes rated for 5x safe working load. These aren’t "options” – they're standard because tunnel crews told us what they need.

Global Compliance for Underground Safety

We offer ATEX Zone 1 and IECEx certified electric motors and control panels for methane-prone tunnels. All surface temperatures are limited to T4 (135°C). Our diesel version includes a flame arrestor, spark arrestor muffler, and automatic shutdown on high exhaust temperature. You get the documentation you need for your risk assessment.

Spare Parts Compatibility

We know TBM crews have limited storage space. That’s why our wear parts (liners, valves, packing, gaskets) are interchangeable with popular brands like Gardner Denver, Wheatley, and NOV. You don't need to stock a unique consumable. Just use what you already have, or buy from us – whichever is easier.

On-Site Technical Support (Yes, Underground)

Our service engineers have worked inside TBMs. They’re not afraid of the dark or the mud. For a fixed daily rate plus travel, we'll send a technician to your jobsite – anywhere in the world – to commission the pump, train your crew, and assist with the first liner change. Video support is always free.

Straightforward Pricing, No "Tunnel Tax”

Some suppliers charge double for "tunneling-certified” equipment. We don’t. Our pricing is based on real costs plus a fair margin. If you need ATEX or special materials, we add the actual procurement cost – nothing more. Request a quote and you'll see the difference.

Frequently Asked Questions (FAQ)

Q1: Can this pump run continuously for a 48-hour TBM shift?

Absolutely. The power end is rated for 24/7 continuous operation with a 100% duty cycle at rated pressure and flow. We recommend changing packing every 300–400 hours and inspecting valves every 200 hours – but the pump won’t stop unless you stop it.

Q2: What about foam injection – won’t the pump destroy the foam bubbles?

We tested this. With standard chevron packing and a 3″ discharge line, our triplex pump reduces foam volume by less than 8% at 100 GPM, compared to 30–40% for a centrifugal pump. For critical foam applications, we offer a low-shear valve design that cuts shear by another 50% – ask about our "FoamGuard” option.

Q3: How do I power the pump inside a TBM?

Two common methods:

• Trailing cable: 400V or 690V AC from the tunnel lighting/power transformer. Our standard electric motor works directly.

• Generator: For small TBMs or remote sections, we can mount a 100–200 kVA generator on a separate skid – but that adds noise and exhaust handling.
  Most customers use the trailing cable. We include a 10-meter pigtail with a CEE plug (or your specified connector).

Q4: Can I use the same pump for bentonite slurry and then switch to cement grout?

Yes, but you must flush thoroughly with water between fluids. Cement grout left to set inside the pump will destroy valves and liners. We recommend dedicating one pump to each fluid if you change frequently. For emergency use, it’s fine – just clean immediately after.

Q5: What maintenance can my crew do underground without specialized tools?

• Adjust packing (external nut)

• Replace valves and seats (socket wrench)

• Replace packing (split gland – no plunger removal)

• Replace liners (requires liner puller – we supply one with each pump)

• Grease all bearings (grease gun)
  Major overhauls (crankshaft bearings, connecting rods) should be done at surface or by our technician.

Q6: Is the pump certified for use in explosive atmospheres (methane)?

Yes – for the electric version with ATEX Zone 1 motor and EX d control panel. The pump itself has no ignition sources (no belts, no open sparks). We provide an EC-type examination certificate and installation drawing for your safety case. Diesel version in ATEX is possible but requires additional ventilation – discuss with our engineering team.

Q7: What’s the typical lifespan of wear parts in TBM service?

Using clean bentonite (no sand) at moderate pressure (500 PSI):

• Liners: 3,000+ hours

• Valves: 1,500–2,000 hours

• Packing: 500–800 hours
  With sandy ground water or abrasive soils, reduce by 50–70%. We recommend a spare parts kit for every 500 hours of operation.

Q8: How long does it take to get a pump and spare parts?

Standard configuration (electric motor, 300 HP, 3″ fluid end): 4–6 weeks EXW Jingzhou. Air freight of spare parts: 3–5 days to most international airports. We maintain a small stock of common liners, valves, and packing in our Houston and Dubai hubs.

Q9: Can you customize the skid to fit my TBM’s gantry mounting holes?

Yes. Send us a dimensional drawing or mounting pattern. We’ll weld the appropriate brackets and drill mounting holes to match. No charge for standard patterns (150mm, 200mm rail spacing). Custom patterns require a small engineering fee – waived if you order 3+ units.

Q10: Do you offer a trial or rental program?

Yes, for established tunneling contractors. We have demo units available for 30-day rental (shipping extra). Rental cost is deducted from purchase price if you buy within 60 days. Ask our sales team for availability.