Horizontal directional drilling (HDD) allows trenchless installation under all kinds of terrain obstacles (roads, rivers, drainage ditches, watercourses, canals, railroad tracks, green areas, etc.), collision-free with existing underground infrastructure (e.g. water and sewage networks , power cables, gas pipes) thanks to the control of the drilling head.
The technology allows for significant savings compared to traditional excavation techniques, due to the shorter implementation time, no restrictions on traffic and no costly reconstruction of the surface.
Call and ask about the drilling
We have drilling rigs
American company Ditch Witch
JT3020 & #8211; with an extremely strong and reliable anchoring system enabling stable operation in the most difficult conditions with a pulling force of 134kN. Ideal for long holes and large diameters. At the turn of February and March 2017, we made a 300m long parabolic drilling machine with a maximum depth of 17m using a JT3020 drilling rig, reaming the hole to DN480 diameter, pulling in 4 pipelines (3 DN 160 and one DN110 diameter).
JT922 & #8211; the shortest drilling rig in its class, enabling smooth operation in small spaces, with a pulling force of 40kN.
- Technical knowledge supported by many years of operator experience, which translates into high quality of service.
- comprehensive services (pipe welding, bentonite removal),
- modern equipment of the renowned American company Ditch Witch,
- drilling length up to 250 meters, diameter up to Φ450,
- competitive prices,
- short lead times,
- execution of orders throughout the country.
Controlled drills are used in the installation of:
- water supply,
- all kinds of pipelines
Due to the specificity of drilling works, we send a price offer on individual customer inquiry. The main price indicator is the length and diameter of the borehole
Description of controlled drilling technology:
Horizontal directional drilling consists in making a pilot hole in the planned borehole trajectory and boring it to the required diameter to insert a pipe or a bundle of cables into it.
Stages of horizontal horizontal drilling:
- pilot drilling
- pipeline pulling
- drilling rig
- Poles that rotate around their axis and at the same time are pushed in along the designated trajectory
- Pilot head with a measuring probe mounted just behind it
- Employee with probe locator
- Head reaming the pilot hole
- Retractable pipe
- Swivel to prevent pipe turning
In the first stage, according to the planned trajectory of the borehole axis, a pilot hole is made. It is performed at a properly planned point, diagonally down under the so-called entrance angle. Then, at the appropriate depth, the horizontal direction is sought. The borehole usually resembles the shape of a parabola. The drilling of the pilot hole consists of pressing connected drill rods together with their rotation at the same time. At the beginning of the drill string there is a pilot head with a control fin, and directly behind it in a special housing there is a transmitting probe, which gives the angle of the head relative to level, depth of the head relative to the surface and the angle of rotation of the probe, i.e. the exact location of the control plate relative to the axis drilling. The task of drilling rods is to transfer the sliding and rotational movement between the machine and the drilling head as well as transporting the bentonite scrubber under pressure from the tanks to the nozzles in the drilling head.
When pressed into the ground and rotating the pilot head at the same time, the borehole trajectory is straight. When the pilot head together with the drill string is only pressed into the ground, without turning, a twist occurs in the direction depending on the position of the pilot head. The diameter of the pilot head depends on the type of soil. Larger diameters are used for softer soils.
During drilling, a bentonite scrubber is fed through the pilot head, whose task is to remove cuttings, cool and clean the head, reduce friction by lubricating the drill string and stabilize the walls of the hole.
After the head reaches the starting point, a properly selected reamer is installed in place of the pilot head. Depending on the diameter of the hole required, the reaming can be single or multiple. A bentonite scrubber is also fed in the boring step.
At the last transition to the reamer, the so-called a swivel, followed by a welded pipeline or a bundle of cables equal to the length of the borehole. During steady rotary return movement, the pipeline is pulled into the widened pilot hole. The swivel is designed to prevent the pipeline from rotating.
In order to reduce the friction forces of the retractable pipeline against the walls of the borehole, in addition to feeding the bentonite scrubber, pipelines use their suspension, placement on roller guides and ballasting by filling it with water or another liquid during retraction.
The following video presents the course of the controlled drilling process
A radiolocation, magnetic and electromagnetic system is used to control the parameters of the pilot hole being made. It consists of the aforementioned probe (transmitter located just behind the pilot head), a portable locator and a monitor for displaying data. The probe emits a radio signal that is received by a portable locator located directly above the transmitter. The locator receives information about the location of the probe, which is transmitted to the drilling rig operator position.
The latest solutions of radiolocation systems, in particular of locators, allow receiving the signal from the transmitter without the need to locate the locator directly over the transmitter. This is especially important when crossing communication routes and water reservoirs. However, the information obtained is subject to a larger reading error.
The course of technological processes during the implementation of controlled drilling:
- Preparatory work,
- transport of machinery and equipment to the construction site,
- determining the appropriate drilling trajectory (based on the relevant technical documentation),
- proper pipeline preparation (welding),
- proper foundation and anchoring of the drilling device - drilling rig,
- preparation of a properly prepared drilling mud,
- securing the construction site and grounding the drilling unit,
- calibration of appropriate measuring devices & #8211; localization,
- choosing the right angle of attack and starting drilling,
- performing pilot drilling and applying location measurements,
- drilling tool change,
- boring (repetitive process - depending on the diameter of the pipeline),
- drilling tool change,
- assembly of the intake head at the beginning of the pipeline,
- pipeline pulling,
- protection of the introduced pipeline,
- registration of ordinates of the arranged installation,
- cleaning and disassembly of machines and devices,
Before pilot drilling began, pneumatic jacking was used to pass under terrain obstacles.
Pneumatic jacking punches are a simple and cheap method of trenchless underground construction, used in Poland for almost half a century. For the creators of the punch used in jacking is considered to be Poles.
However, jackbacks have some limitations. First of all, this method can be used in compactable soils, because there is no spoil removal, and excess soil is compacted around the pneumatic punch.
Another limitation of the use of pneumatic jacking is the maximum outer diameter of embedded networks. It is maximum 300 mm. On the other hand, the lengths of one-time built-in sections of the network are relatively up to 35m, and in the guided jack method up to 70 m