Natural gas line installation

Ngày đăng: 06/04/2021

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With a simple natural gas line installation process, shorten the construction time, less impact on the environment and living activities of the residents around the construction area.

Natural gas line installation

Oriented drilling technology is currently used a lot in urban areas. The reason comes from the outstanding advantages of this technology.

Most wells drilled for water, oil, and natural gas are drilled in the vertical direction. However, this method can lead to environmental pollution. Meanwhile, it was found that drilling at a better vertical angle could hit the target and obtain information more efficiently. That is the reason that oriented horizontal drilling technology was born. And now this is a drilling method that is used a lot by its outstanding advantages.

The applications of directional horizontal drilling technology

The directional horizontal drilling technology provides a solution for underground pipe installation without the need for open excavation. Therefore, this technology is applied in many cases such as:

Used for underground pipe installation works on roads.
Installing small diameter electric, telecommunication, and water supply pipes.
Mount pipes up to 300mm in size with a maximum distance of 60m.

HDD-oriented pipe pulling technology is a new method of pipe construction with controlled underground drilling, the direction of the drill, which can control the direction of the drill in the predetermined direction with angles up and down through sales. Permissible curved glass of drill rod.

Underground drilling technology has many advantages such as high working efficiency, very economic efficiency, no influence on the surface, allowing control of the drilling direction, the direction of drilling, so it has outstanding advantages over traditional construction methods and other modern, unexplored modern technologies are experimenting and applying in Vietnam.

Gas pipe installation guide

With a simple natural gas line installation process, shorten the construction time, less impact on the environment and living activities of the residents around the construction area.

Drilling cycle in 03 steps:

B1. Pilot bore: positioning the alignment by GPS (positioning device is attached to the drill head)

B2. Drilling: Backward drilling and reaming in opposite direction.

B3. Pipeline installation.

Specifically:

I. Steps to drill natural gas line installation

1. Pilot bore

Based on the blueprint, use the TriHawk drill bit to drill at a suitable inclination angle. When the drill head reaches the design turning point, adjust the tip of the drill head to an angle of "12 clocks" and then use the thrust to gradually change the direction of the drill to the horizontal with the predetermined depth according to the design. Then continue the traversing traverse using a rotating technique - pushing the drill head until the turning point goes up. Continue to adjust the tip of the drill head to the "12 clocks" angle and use the drill head thrust to advance towards the pre-set target point. During the drilling process, the drilling fluid is pumped to the drill head through a tank - pump - system that is needed to lubricate the drill head.

Direction control is controlled based on the asymmetric mechanism of the drill bit mounted on the drill head. The whole signal serving the direction of the drill head is determined by the transmitter inside the drill head, this transmitter must be continuously active during the drilling and ensure to send the signal. at least 25m away from upwards.

Right above the drill head, a receiver is used along the route to follow the movement of the drill to determine the parameters: depth, temperature, rotation angle, and inclination of the drill head.

This information is transmitted by the detector via radio waves to the remote display device placed on the drill to help the machine operator orient the drill towards the design depth and direction.

For construction across rivers, lakes, seas, ... the transmitting device will broadcast directly to satellites and transmit back to the terrestrial transceiver system and display device on the monitor screen. The directional drill line must be strictly controlled to follow a predetermined direction by the design and must strictly comply with permissible tolerances.

The drill data recorded by the software can be easily verified.

End the guide drilling process when the drill goes through the predetermined route.

2. Backreaming to expand the drilling line (back reaming)

After the directional drilling is completed, the TriHawk drill head and the drill bit will be replaced with a reamer. Applying the rotation-drag technique to bring the lagoon back to the drilling machine at a speed consistent with the geological strata that the drill line goes through with a suitable amount of drilling fluid pumped in, the reverse head has the effect of widening the drill line into a line to create a pipe filled with drilling fluid with a diameter equal to 110% of the planned pipe size to be installed. The operation of the lagoon must comply with a process calculated based on the engineering geological report to ensure the wall strength of the tunnel to maintain a good quality of internal drilling fluid during construction. . Maintaining the stability of the tunnel and the quality of the internal drilling fluid are decisive to the success of the next drafting, especially for drilling lines greater than 1,000m in length.

At the end of the stage, Nong moves to step 3.

3. Pipeline installation

3.1. Pipe pulling technique.

The pipe is pulled by the force transmitted from the drill through the back-breaking structure attached to a rotating joint with a rotating technique - pulling the drill rod gradually towards the drill. The drilling fluid is pumped into the tunnel with the right mode to minimize friction on the pipe body, preventing the possibility of tunnel collapse.

Pipe pulling is carried out with a timetable carefully planned to every detail by the length of the drill line and must be done continuously, with absolutely no downtime. The larger the drilling length, the more geological layer changes leading to a higher risk of the pipe body load. The drilling fluid must be carefully calculated to always ensure the movement along the pipe body to help lubricate, reduce the possibility of stuck in the process of pulling the pipe.

The pipe pulling parameters are often unstable, so the person in charge of the engineering must always take into account the case of increased tensile load and reserve the plan to change drilling fluid, tensile speed.

II. Relevant contents should pay attention in the work of underground natural gas line installation

1. Drilling fluid used for construction

a) Function of drilling fluid.

Drilling fluids are an important ingredient in the success of drilling. Basically, the drilling solution is a mixture of water, bentonite, and additives. The amount of bentonite used is calculated based on the geological parameters of the project and the diameter and length of the drill line.

The drilling fluid has the following functions:

- Mix soil, rock, sand in the tunnel where the drill head and the lagoon pass through when it is pumped with high pressure.

- Establish and maintain tunnel stability (avoid tunnel collapse).

- Lubricate drill heads, breakers, and drill rods, reducing heat concentration on these tools.

- Transporting soil, rock, and sand in the tunnel.

With the geological region of salinity or high pH, several additive components are added to limit the deterioration of these functions:

- Main agent: Aus - Gel

- Au. Agent: XAN BORE

- Au. Agent: AMC - Pac – R

Another important feature of the drilling fluid is that it is reusable through the use of recycling equipment: The bentonite solution tank consists of a storage tank system, a filter tank, and a sedimentation tank.

b) Drilling fluid mixing techniques

Mixing the drilling fluid in the correct ratio and mode to form the mixture to match the required parameters of the project requires knowledge and experience through many drilling projects.

Personnel Minh Phuong Corp has been trained directly in Vietnam by experts in both theory and practice on the site. Thereby, applying to the project, depending on the geological condition, the staff and experts of the company will add special additives that can help reduce the load, further prevent stickiness for the drilling head and increase. flexibility and resistance to drilling fluid loss in tunnels.

2. Arrangement of drilling machine anchoring system, floor frame.

Anti-slip drilling anchors play a very important role in the drilling construction process. The machine unstable when drilling will cause the additional load to bend the drill rod, reduce the transmission capacity to the drill head/breaker, creating the risk of labor accidents. When the instability is increased without a solution to the destruction of the foundation where the drill is placed, the machine is tilted excessively and it is imperative to rework the foundation, floor, and stabilization anchors. construction can be continued. The time and cost spent for this re-treatment are at least 2 times if it meets the requirements from the beginning.

Thus, the positioning of the drilling machine plays a very important role in ensuring the construction progress, preventing accidents and incidents.

Construction experience and professionalism and methodology of the construction team play an important role in the field assessment of the foundation, giving the right handling solution from the beginning.

The platform is applied for soft ground and must be assembled from large plate-shaped complexes such as H, I, U, Larsen steel piles together with a steel clamping system, absolutely no cajuput sheet is used. lanyard, ... and forced to achieve a rejection by a pile press. To prevent vibrations and subsidence, sandbags are compacted to form a solid surface. After completing the floor, the floor must be tested to load and repair immediately the points still subsidence, subsidence ...

Learn more UNDERGROUND CABLE INSTALLATION METHODS