Views: 27 Author: Site Editor Publish Time: 2019-10-01 Origin: Site
1. Construction Profile
Project name: LNG subsidiary project Pipeline directional drilling crossing Phase II
Proprietor / Development unit：CNOOC Eastern Guangdong Liquefied Natural Gas Co.,Ltd
Construction unit: Henan Jinchang Petrochemical Construction Co., Ltd
Project characters: Rongjiang River Ф914mm*1400m natural gas pipeline(steel pipe) crossing project,once again complete the achievement of crossing rivers by large series horizontal directional drilling (HDD) machine.
Geological condition: Entry point and exit point are both clay, most of the crossing stratums consist of silt and sand.
Project difficulities:The geological condition below the river is complicated, too much slit and quicksand ,hard to ream.
Picture 1：The topography of Rongjiang River
2. Construction equipments
“Goodeng mechine”GS5000-L HDD machine, “Goodeng mechine”GN2500 mud pump, “American ParaTrack2” Locator and etc.
Picture 2：＂Goodeng Machine＂GS5000-L HDD machine
Picture. 3：＂Goodeng Machine＂GN2500 Mud pump
Picture 4：“American ParaTrack2” Locator
Risk prevention: No lead from the process, shorten the construction period as much as possible;
Five reamer diameter: 600mm、750mm、900mm、1050mm、1250mm;
Pull back the pipe: adopt 1250mm with pull back pipe.
4. Construction procedure
Pilot：7 days，Speed: 7-13 min/pipe ，Push&pull force:5-13MPa.
Phase I Reaming: Ф600mm Barrel Reamer, Torque: 13-15MPa,Pull force: 3-4MPa, Mud pump flow: 1300L/min;
Phase Ⅱ reaming: Ф750mm Barrel Reamer, Torque: 11-15MPa,Pull force: 3-4MPa, Mud pump flow: 1300L/min;
Phase Ⅲ reaming: Ф900mm Barrel Reamer, Torque: 10-17MPa,Pull force: 3-4MPa, Mud pump flow: 1300L/min;
Phase Ⅳ reaming: Ф1050mm Barrel Reamer, Torque: 10-17MPa,Pull force: 3-4MPa, Mud pump flow: 1300L/min;
Phase Ⅴ reaming: Ф1250mm Barrel Reamer, Torque: 10-17MPa,Pull force: 3-4MPa, Mud pump flow: 1300L/min;
Washing hole: Ф1250mm Barrel Reamer, Pull&push force: 8MPa, Torque: 10MPa, Mud pump flow: 1200L/min;
Drawing: From 18:00, Sep. 12, to 13:00, Sep. 13, 2019, Lasting 19 hrs
Starting Pull force: 8MPa. Torque: 10MPa. Process pull force: 8-20MPa. Mud flow: 1400 L/min.
Starting time:18:00 Sep. 12, 2019. Finishing time: 13:00, Sep. 13, 2019. Lasting 19 hrs.
Picture 5: Starting piloting
Picture 6: Ground reaming
Picture. 8: Under pulling
Picture 9: Success of pulling back pipes
5. Auxiliary Mud
Bentonite Amount：250-280 t
Mud ratio：5% bentonite，0.1%-0.2% Salt Resistant Adhesive,0.15% Lubricant
Mud parameter: Marsh funnel viscosity 50S-60S, apparent viscosity 26mpa.s, plasticity viscosity 12mpa.s, dynamic shear force 8pa.
Picture 10: Happiness of Succeeding pulling back pipes
6. Project Conclusion
Henan Jinchang Petrochemical Construction Co., Ltd’s completement of CNOOC Eastern Guangdong LNG Rongjiang River Pipeline crossing project is another success after Hangjiang Dongxi city Crossing of the project. Both of the two projects are finished by using “Goodeng Machine”HDD machine, setting an example for crossing complicated geological conditions and accumulating experience for work under hard conditions at home in future.