The M-COATING system is an effective manhole shaft renovation technique and is a very safe procedure. This is true for general safety levels onsite, as well as a high level of personal safety for the operators. The safety procedure have been over ten years in development, involving planning and responding to clients’ requirements and feedback.

Highlights of the system include:

  • All equipment and machines are securely installed in a trailer or on a transporter, and cannot slide or topple.
  • There is a system for tying attachments down or stowing them away.
  • Every vehicle is equipped with lights on all sides for easy visibility in traffic, and safety onsite.
  • Transport accidents are eliminated as far as is humanly possible.
  • The equipment is spaciously designed, to a high technical standard, and can easily cope with extreme operational demands.

Cleaning the structure

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In its M-COATING system, Hermes offers fully automated shaft cleaning using high pressure water jets (TSSR). The latest development, HDS jet, is a fully automated sand and water blasting unit. When using these cleaning techniques, there is no need to enter the shaft to carry out jetting. The whole process is set up and monitored from above the shaft.

Although the operator is not working in the immediate vicinity of the jets, and so not in a confined space, in order to comply with the relevant health and safety rules protective clothing must be worn.

The TSSR – the cleaning rig that travels automatically up and down within the shaft – can be installed in the gap between the winch and the top edge of the shaft, controlled by an easily accessible, adjustable limit switch.

This avoids the TSSR being raised higher than intended, preventing injury. Even if the operator is briefly distracted, the system automatically switches itself off when it reaches the set level.

The high pressure hoses, the mortar-flushing hose, a hose for the hand-lance and the TSSR are always attached to the high-pressure distributor unit. An additional pressure gauge is fitted to the distributor unit, so that the operator can see immediately whether the system is still at the optimal pressure. The mortar-flushing hose is also equipped with a safety valve, so that too much pressure is not used when pumping hoses clean.

Re-coating

During coating, the operator stands beside the shaft, as when supervising the automated coating process. A colleague on the mixer is largely protected from dust thanks to the feed hopper, specially developed for the M-COATING system.

The operator is further protected by the suction funnel that is mounted over the feed hopper, and by a protective mask. Water is automatically measured out, and the mortar is automatically mixed. The mortar drops into the grout tank and from there, is safely pumped to the centrifuge motor through sturdy mortar hoses. A pressure gauge at the pump outlet gives a constant reading of pump pressure.

Once coating is completed, all attachments are flushed through potable water.

To prepare the rig for leaving the site, all attachments and hoses are tied down or securely stowed away, as described above. They remain in position even if the vehicle corners or brakes abruptly.

The generator and HP pump batteries are automatically charged up during transport, in readiness for the next job. The floor of the vehicle is covered in a non-slip coating.

Thanks to the company’s years of experience and a constant exchange of ideas with clients and safety experts, the M-COATING system has achieved the highest level of safety.