During subsea tunnel shield tunneling, gases in the strata, the foaming agents used by earth-pressure-balance shield machines, and complex geological conditions easily generate large amounts of stubborn foam. This foam not only reduces the fluidity of the muck and affects the efficiency of muck discharge, causing the advance speed of the shield machine to decline, but may also clog pipes and screens, increase equipment wear, and even trigger pressure imbalance inside the chamber, directly threatening construction safety and the project schedule. Traditional physical defoaming methods are often limited in effect and struggle to cope with continuously generated, highly stable foam.
Chemi Tech focuses on the research and development of engineering chemical additives. Addressing this industry pain point, we have launched a series of high-efficiency shield-dedicated defoamers. Our solution is based on in-depth research into the shield tunneling process and the causes of foam; the product features rapid foam breaking and long-lasting foam suppression, and effectively adapts to the high-pressure, high-shear, and complex slurry environment inside the shield machine.
Our solution steps are clear and definite: First, the technical team performs an on-site or online diagnosis of your specific engineering geology, the foaming agent system in use, and the current foam problem. Then, based on the diagnosis results, we recommend or customize a suitable Chemi Tech defoamer model for you. We provide detailed guidance on the dosing point, dosage ratio, and operating procedure to ensure the defoamer is perfectly compatible with the shield tunneling system. In the initial application stage, our engineers can provide remote or on-site support, monitor the defoaming effect in real time, and make fine adjustments based on feedback until a stable and ideal control state is achieved.
In a shield tunneling project for a cross-sea passage in East China, the contractor once faced the dilemma of poor muck discharge and a sharp reduction in the number of rings advanced per day due to excessive foam. After introducing the Chemi Tech defoamer solution, following three days of systematic debugging and adaptation, the foam in the shield chamber and the muck discharge pipes was significantly suppressed, the muck conditioning effect improved, and the equipment's operating resistance decreased. The project ultimately achieved about a 30% increase in muck discharge efficiency, and the shield machine resumed and maintained a stable design advance speed, safeguarding the schedule of key milestones.
Choosing Chemi Tech means choosing reliable technical support and proven product performance. We are committed to being your trusted partner in tunnel construction, jointly overcoming construction challenges and ensuring the project advances efficiently and safely.