Shield dispersant is a chemical additive that prevents clay clogging (mud cake formation) on the cutterhead and in the excavation chamber during tunnelling in cohesive ground. In clay
Shield foaming agent is used for soil conditioning in EPB tunnelling. The foam solution (agent + water) is mixed with compressed air in a foam generator to produce fine, stable foam,
The main bearing is the most expensive rotating component of a TBM. Water or sand ingress can cause catastrophic failure. HBW is a high-viscosity EP (extreme pressure) seal grease,