1、 Project Summary
This project for the Indian government image—- natural gas pipeline project from the westIndia to New Delhi，Mainly crossing the Yamuna River of UP state ,India, pipe material is steel pipe with diameter Ø 915 mm, crossing length 2000 meters.
The project owner: Gas Authority of India.Ltd(GALL).
Construction party: TRENCHLESS ENGINEERING SERVICES PVT LTD
Project characteristics: Confirmed by the official, project of directional cross the Yamuna river with steel pipe Φ915mm×2000m which refresh India’s national record of 350T Drilling rig’s crossing length .
The Soil conditions: Through the formation of river silt, soft sand layer, etc.
The terrain conditions: Through the terrain elevation difference about 15 meters, Need through flood-preventiondams and rivers,the depth of river is 6 meters,and the width of river is about 200 meters.
Project challenge: River silt and quicksand layer make it difficult to form the pilot,and pipe weight over 800 ton,So the pulley bracket will be used during the process of construction to reduce the pipeline friction with the ground.
Picture1：GD3500-L(S) Drilling from Goodeng Machine, China
2、 Construction equipment
Horizontal directional drilling rig adopts GD3500-L(S) Drilling from Goodeng Machine, China , and Guide device adopts ParaTrack2 Magnetic orientation instrument from America, and mud pump adopts F500(2000L/min) from Mitsubishi Japan.
Picture2： （Yamuna River）
Picture3： GD3500-L(S) Drilling from Goodeng Machine, China
Picture4： ParaTrack2 Magnetic orientation instrument from America
Picture5： F500 (2000L/min) mud pump from Mitsubishi Japan
Adopts seamless process to reduce the Construction period. And use ParaTrack2 Magnetic orientation instrument.
Level 4 reaming:20 inches(500mm),36 inches(915mm),42 inches(1067mm),48 inches(1219mm).
Drawn tube: Using the 1066mm (42 inches) barrel reamer for pulling back.
4 、Construction Process
Guiding holes:Six days,Guiding speed 1rod/15min,Max mud pump flow:600L/min,Torque:10-15Mpa,Push&pull force:5-7Mpa.
Reaming level 1:20inches(500mm) cutting reamer, river silt, and quicksand layer speed:1rod/20min,mud pump flow:800L/min,Torque:15-18Mpa,pull force:6-10Mpa.
Reaming level 1:36inches(915mm) cutting reamer, river silt, and quicksand layer speed:1rod/24min,mud pump flow:1000L/min,Torque:17-22Mpa,pull force:11-15Mpa.
Reaming level 1:20inches(1067mm) cutting reamer, river silt, and quicksand layer speed:1rod/29min,mud pump flow:120L/min,Torque:19-25Mpa,pull force:15-20Mpa.
Reaming level 1:20inches(1219mm) cutting reamer, river silt, and quicksand layer speed:1rod/35min,mud pump flow:1500L/min,Torque:21-27Mpa,pull force:18-23Mpa.
Hole clean: 48 inches Barrel cleaner, clean speed:1rod/18min,mud pump flow:1500-1800L/min,Torque:18-25Mpa,pull force:15-23Mpa.
Draw pipe: 42 inches Barrel drawer, Began drawing at the evening of April 19, 2016,Torque:21Mpa,back draw force:31Mpa,draw speed 3/min, mud pump flow:1800L/min, the back drag force and torque are maintained between 19-28Mpa and 18-23Mpa, respectively. In April 2016 23 the drawing pipe, which lasted more than 70 hours success.
Picture6： Project site
Picture7：Tracking under construction
Picture8：36 inches (915mm) reaming
Picture9：48 inches (1219mm) pilot cleaning construction
Picture10： Preparation before drawing tube
Picture11：Preparation before pulling the pipe
Slurry proportion: 4%ordinary bentonite and 0.15% salt raised adhesive, 0.15% lubricant.
Mud parameters: Marsh funnel viscosity 55 s – 65 – s, apparent viscosity of 26 Mpa. S, plastic viscosity 12 Mpa. S, dynamic shear 8 pa
Picture12： Start of pulling the pipe
Picture13：Pipe pulling under progress
Picture14：Pipe pulling under progress
Picture15：News reporters waiting anxiously
Picture16：Pipe pulling completed – The great moment
Picture17： Scene cheering, scrambling to take picture with rig
Picture18： The owner, the construction party, news reporters and other common witness “the most of India” was born
6、 Project conclusions
It is very important to use bentonite during the construction process in the area of the formation of river silt, quicksand layer. This kind of strong compressibility of strata should reduce The time of reaming .Also the continuity of the construction is very important. Working condition of long borehole trajectory is Angle to the pipe axis, send groove is effectively solve the difficult into the hole and the effective method to pipe the weight.
The project was undertaken by “Goodeng Machine” GD3500 -L (S) of horizontal directional drilling, India in recent years with the diameter of the construction of the most challenge , crossing the longest distance of trenchless pipeline laying works. And set a model for the complex environment, long distance directional crossing again. Also laid a solid foundation for Chinese large-scale horizontal directional drilling rig to enter the India Market.