Pipelines


S.No. Area Title Description Action Status
1 Maintenance cost of sub-sea pipelines We are looking for benchmarks w.r.t. cost of maintaining sub-sea pipelines being operated by upstream O&G companies mainly on account of various maintenance activities viz. maintenance pigging, corrosion monitoring (using various probes viz. ER, LPR, weight loss coupons and non-intrusive methods), health assessment of pipelines using conventional intelligent pigging and non-intrusive technologies (ICDA-ECDA / MTM etc.), periodic acoustic surveys of pipeline network, CP survey, free span correction, augmentation of sacrificial anodes, maintenance of pigging facilities (replacement of faulty valves associated with pigging, hinge closures, pig indicators), hiring of consultancy services etc. in terms of %age of pipeline replacement cost of complete pipeline network. (if total replacement cost of all the pipelines is INR 10000 crores and cost incurred in maintenance of pipelines is 100 crores, then it is 1%) Age of pipelines varies from 2-40 years. Separately we would also like to know the repair cost of sub-sea pipeline being incurred by various operators in %age terms of pipeline replacement cost of complete network. Any official document published by operators / POF / Institutes on expenditure incurred by major pipeline operators globally?
2 How to repair, pipeline to casing shorting happened, within the Casing? Short description: The methodology to be adopted for the repair of the pipeline and casing shorting, within the casing laid under road / rail crossings Detailed description: We are looking for the solution for the repair of pipeline and casing shorting within the casing. We have a pipeline which is crossing Highway and Rail Track (Highway and Rail Track are running parallel to each other) at 90 degree under a 100 m long casing pipe. While carrying out regular CP monitoring of the pipeline, we found that the carrier pipeline and casing are giving same PSP value of (-) 0.77 v. This common PSP of both, is basically due to shorting of the carrier pipeline and casing. We had opened up the end seals of the casing and tried to clean the casing through pneumatic air, but there was no improvement. Considering the long length of the casing it is difficult to find out the exact location of the shorting. We are trying to bring the PSP of the casing to more than (-) 0.85 v, by putting additional sacrificial Mg Anodes within the vicinity of the casing. However, getting any job under the Railway ROW is very difficult. We wish to seek information under this forum, as any measures taken by pipeline operators for repair and for restoring the pipeline PSP value to its original value of (-) 0.85 to (-) 1.20 v with external measures, without affecting the integrity of the carrier pipeline and casing.
3 How to handle the passing issues of SV station valves? In a cross country pipeline, even after carrying out the necessary maintenance activities, the passing of Sectionalizing valves cannot be ruled out. In case of exigency, with the passing sectionalizing valves, isolation of pipeline section would be difficult & hence, a concern area. How the industry is addressing this issue?
4 Corrosion Inhibitor (CI) dosing in LPG pipeline In Pan India LPG pipeline network, Pipeline operators follow different practices in dosing of Corrosion Inhibitor in pipeline. Industry view is sought on the benefits / results achieved post dosing of Corrosion Inhibitor in LPG pipeline.
5 Repair of High Pressure NG / LPG Pipeline What are the methods for repair of High Pressure Natural Gas / LPG Pipeline in operating condition, their selection criteria and comparison w.r.t safety and integrity?
6 Emergency handling in Sub-Sea POL /LPG Pipelines India has a growing network of Hydrocarbon Pipelines. These lines are laid through various terrains in on-shore and at varying depths in off-shore section. The challenge for the pipeline operators is to attend the emergency (arising from hydrocarbon leakage from pipeline into the environment) in the least possible time and restrict the loss of human life and property. Though various emergency response & repair systems are in place for onshore lines, offshore lines still remains a challenge for the pipeline maintenance team. Query 1. – What is the methodology for attending a leakage from sub-sea pipeline (MS/HSD/SKO/CRUDE/ATF) due to damage by either ship’s anchor or any other reason. Query 2. – What is the methodology for attending a leakage from sub-sea LPG pipeline due to damage by either ship’s anchor or any other such reason. Remarks – 1. Evacuation of entire LPG from line by hot flaring at SV stations doesn’t ensure that the pipeline is hydrocarbon free. 2. The visibility is poor as the water is turbid in the shallow sea, thereby making maintenance activities difficult to execute. Query 3. – What is the philosophy & procedure to refurbish the coating (pipeline protective coatings / concrete) removed during sub-sea line repairs? Query 4. – What kind of flaring should be used (Hot or cold) during evacuation process of the LPG pipeline? Remarks – 1. As per our knowledge, options available are mobile & fixed flaring unit. Limitations are on the cold flaring quantity per hour. 2. There are statutory limitations on space around the permanent hot flaring area.
7 Repairs of Pipeline laid using HDD technique India has a growing network of Hydrocarbon Pipelines. These lines are laid through various terrains in on shore and at varying depths in off-shore section using HDD technique. The challenge for the pipeline operators is to attend the emergency (arising from hydrocarbon leakage from pipeline into the environment) in the least possible time and restrict the loss of human life and property. Query 1. – What is the methodology for attending a Corrosion leakage from Pipeline laid using HDD (Horizontal Directional Drilling) technique . Query 2. – What is the methodology for carrying out repair of Pipelines laid using HDD (Horizontal Directions Drilling) technique identified after I.P. Survey. Remarks - HDD method is widely used from crossing the large / perennial water bodies. However the risk of leakage inside the HDD cannot be eliminated. In such case the line will be isolated across the water body using sectionalizing valves immediately. Challenge is how to access and repair the line inside HDD deep down in the sea bed.