Optimization of the Process of Connection/Disconnection of Slurry Pipes During the Construction of a Tunnel

50000.00 EUR
Review deadline: 
Saturday, May 18, 2019

The Seeker is a tunnel boring machine that produces small diameter (600mm) underground structures with medium diameters (2600mm) based on prefabricated modules (concrete, GRP, sandstone or other composite materials).

As part of its achievements, the Seeker must descend these modules at the bottom of the borehole and then push them one after the other using a thrust bench powered by hydraulic cylinders. (video explaination: https://youtu.be/ccD4AxFoTEk)

This handling requires the connection and disconnection of many pipes and connectors, tedious steps that do not represent the actual working time. There are several pipes and connectors:

● 2 slurry pipes (length: 2-3m, diameter: 85 to 125 mm depending on the size of the microtunnelling), one for transmitting pressurized water to the drill head and the other to evacuate the sludge recovered during drilling. For small diameter tunnels, these 2 pipes are lowered, sometimes coupled by a twinning piece within each concrete module.
Example for an AVN600XC Microtunnelling
Slurry pipes DN100 (2x 2m)

These pipes have a very varied type of attachment system, "Bauer" connection or "victaulic" connection for example, often clogged with mud and other impurities, are taking long time to connect and disconnect. Their weight (100Kg or more depending on the diameters of the modules) makes handling difficult for operators. These pipes are connected to other semi-rigid pipes of the same section connected to the lift pump to evacuate the recovered sludge.

● 4 black hydraulic hoses (length: 6 ml in general, diameter: variable according to their functions and the size of the microtunnelling) ensuring the hydraulic supply of the cutting wheel and the guiding cylinders of the machine at the front of the tunnel
Example for an AVN600XC Microtunnelling
30S (DN25) Cutting Wheel Drive (2x 6m)
8S (DN06) Steering Hose (6m)
8L Return Oil Hose (6m)

● 1 black hydraulic hose (length: 6 ml in general, diameter: variable according to the size of the microtunnelling) intended to pressurize lubrication products. Allowing the section to slide better during the pushing. Fixing these pipes is still done with a wrench.
Example for an AVN600XC Microtunnelling
18L (DN16) Bentonite Line (6m)

● One or more orange data cables (Length: 6 ml in general, diameter: variable depending on the size of the microtunnelling) allowing the electrical connection of the target.
NB: the configurations depend on the types of microtunnelling but for the example of the AVN600XC, it is a hydraulic motor.
Example for an AVN600XC microtunnelling with target in 37 poles
37-pin Data Cable (6m)

● Ventilation pipe for the largest diameter of modules (Length: variable, diameter: variable) allowing aeration within the tunnel. The connection of this pipe is made using tape to attach the sleeve to the air intake. Rare on small diameters.

Today, the handling time between the end of thrust of the previous concrete module and the beginning of thrust of the new module is about 30 minutes for the small diameter (400 mm) up to 2-3 hours (rather 2h) for larger diameters (2600mm). The space between the push bench and the thrust helmet limits the movement of operators already hampered by a slippery and sluggish environment.

Through this challenge, it is this unproductive time (= no-thrust time) that the Seeker seeks to reduce by optimizing, simplifying, shortening the steps of connection and disconnection of all these pipes and connectors. By making handling easier and faster, it is the improvement of the productivity and the cost of the microtunnelling which is above all sought after. Evolving in a wet and slippery environment, the simplification of this handling will reduce, if possible, the arduousness as well as improve the safety of the operators. On a day of 8 hours about 30% of the time can be taken to make these connections.

The total gain of each step will have to reach 50% of unproductive process time.

Order of idea of the time required at the end of thrust of a pipe and the beginning of thrust of the following pipe:
DN 600 800: 30 minutes
DN1000: 40 minutes
DN1200: 50 minutes

For the full information, please check the pdf document below. For submitting your innovative solution, please register (or login if you already have an account) and then you will find a submit solution button below on this challenge page.