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Pioneering Underground TechnologiesPioneering Underground Technologies

CORE PRODUCTS

Tunnelling

EPB Shield

Mixshield

Single Shield TBM

Double Shield TBM

Gripper TBM

Partial-face Excavation Machine

AVN Machine

Auger Boring Machines

HDD Rig

Direct Pipe

Vertical Shaft Sinking Machine(VSM)

Mining

Exploration

ADDITIONAL EQUIPMENT

Your contact person

Michael GroProduct Manager Pipe Jacking| Utility Tunnelling

Phone +49 7824 302-4340Gross.Michael(at)herrenknecht.com

Partial-face Excavation Machines areequipped with excavators or roadheadersdepending on the project's geology.

Partial-face Excavation MachineEconomical tunnelling technology with highflexibility________________ Partial-face ExcavationMachines made by Herrenknecht are aneconomically interesting solution in homogeneousand almost stable grounds with little or nogroundwater. This tunnelling technology can beeasily adapted to changing geological conditionsboth in loose soils and in hard rock due to itsstrikingly simple design.

One machine, two excavation methodsHerrenknecht shields with partial-face excavation can excavate the soil with two differentcutting tools. In loose soils, the excavator has proved its great value hundreds of times. Theuniversal excavator boom is equipped with a shovel, a ripper tooth or a hydraulic jackhammer depending on the soil conditions. Roadheader booms are used in harder rock with uniaxialcompressive strengths of up to 80 megapascal. Both boom technologies allow quick and easyreplacement of the worn tools. The excavated material is transported by belt conveyors orchain conveyors to the conveying system in the back. The application range of Partial-faceExcavation Machines starts at around 1.5 meters, as it is necessary to access the tunnel.Tunnelling operations with diameters of more than 10 meters can be carried out costeffectively using additional support measures or grout injections to improve the ground.

PROJECT CONFIGURATOR

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Your Selected Files 00Partial-face ExcavationMachinePartial-face ExcavationMachine data sheet

Illustration of a typical Partial-face Excavation Machine with roadheader for pipe jacking

Machine operators workplace with direct viewof the tunnel face for precise control of theexcavation.

GEOLOGY & DIAMETERS FUNCTIONALITYFUNCTIONALITY ADVANTAGESADVANTAGES

Direct visual contact with the geologyOne advantage of Partial-face ExcavationMachines is that the workplace of the operator isjust a few meters away from the open tunnel face.This makes it possible to control excavationprecisely, react swiftly to changes in the groundand take appropriate measures if necessary. Oneexample is the excavation and removal of largeboulders or obstructions without having to createadditional shafts. Direct visual contact with thegeology is also an advantage for the steeringprocess. In pipe jacking, the machine is controlledusing steering cylinders and an articulation joint inthe front section of the shield. With larger

diameters and during segmental lining, the machine is steered via the main thrust cylinders inthe same way as closed-shield machines.

ExcavationEither a roadheader or an excavator remove the soil

Tunnel face supportMechanical support, e.g. extended forward shield at tunnel crown or transverse platforms

RemovalBelt conveyors or chain conveyors provide efficient removal of excavated material

ThrustHydraulic thrust cylinders in the shield or a jacking frame in the launch shaft push the machine forward

Partial-face Excavation Machine ( 11,770 mm)with two cross-bracing platforms, telescopic faceplates in the crown and three flexible excavators.

Safe in hard rock. Partial-face ExcavationMachines with roadheader booms can also beused in geologies with up to 80 MPa compressionstrength.

Tunnel liningPipe jacking or segmental lining

+ Usable in almost all non-groundwater-bearing geologies+ Various excavation tools for various geologies available+ Easily and quickly convertible+ Exact control of the excavation process: the operator is just a few meters away from the open tunnelface+ Low operating costs

Always on the safe sidePartial-face Excavation Machines are opentunnelling shields that do not have a closedsystem for pressure balance at the tunnel face toprovide soil and groundwater support. Therefore,various mechanical methods are used to ensureadequate support and to protect the machineagainst groundwater inflow.

Almost all Partial-face Excavation Machines are designed as forward shields. The rim of theshield and its leading edge are extended forward at the crown section in the direction of drive.Thus the repose angle of the surrounding ground is corrected to ensure controlled removal ofthe excavated material. At the same time, no soil can break away from the top and settlementcan be avoided. The entire shield can also be designed as a so-called poling plate system withthe shield divided into several plates which can be extended individually towards the front. Inchanging ground conditions this means that the natural repose angle can be adjustedcontinuously. Larger diameter machines are equipped with one or more horizontal supportplatforms, which also control the repose angle of the geology. This type of open-face machineallows installation and operation of several excavation tools at a time on different transverseplatforms increasing excavation speed. Often, hydraulically extendible or telescopic faceplates are also installed especially in the crown. They support the tunnel face mechanicallyand are partially retracted during excavation.

In partially water-bearing soils, the Partial-faceExcavation Machines and a part of the tunnel canbe supplied with compressed air through anairlock system. This prevents intrusion ofgroundwater. The operators workplace is locatedin the protected pressurized section. Acompressed air system consisting of two controlloops continuously verifies the required pressureand performs the corresponding adjustment, ifnecessary.

Easily and safely to breakthroughPartial-face Excavation Machines made by Herrenknecht are directly controllable, easy tohandle, easily convertible and can be used in different geological conditions. The machinesachieve good and stable advance rates in suitable grounds at attractive investmentconditions. Therefore, they can be an ideal solution for constructing tunnels, both in pipejacking and segmental lining. Moreover, the exterior diameter of the Partial-face ExcavationMachines can be extended flexibly using an upsize kit. They can therefore be usedsuccessfully in several projects with varying diameters.

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