RIASSUNTO
ABSTRACT:
This paper presents the salient aspects and details regarding design, construction and commissioning of Oil and Natural Gas Commission''s (ONGC) Heera-Uran Trunkline (HUT) Project, which is an integral part of over-all development of Bombay Offshore Oil Field, India. Preliminary pipeline route selection and route survey to identify the rocky areas, existing pipelines within Bombay Port Limit as well as at Platform approaches were completed as early as 1985. The environmental parameters were finalized based on review of various Met ocean studies carried out for this region in mid-198B enabling the engineering to commence immediately thereafter. The trunk lines were originally designed to transport the crude oil and natural gas from Heera and some adjoining fields through 85 km long twin pipelines of 18"" diameter and 20"" diameter to the existing shore installation for oil/gas handling at Uran. However considering inter-connection of various oil/gas fields in Bombay Offshore area, an integrated pipeline network for effective transportation of oil and gas was devised. Linepipe coating was carried out at an Indian coating yard between March and October, 1989. Contract for pipeline installation was awarded in mid-April, 1989. The Lay Contractor carried out the pre-engineering survey which included selection of site for crossing two existing pipelines in rocky seabed within the Port Limit and identification of the pipeline corridor in approaches to the Offshore Platform where interferences with the existing pipelines as well as one new pipeline being laid in the vicinity in the same installation period were a problem. The installation of the pipeline commenced with the start of pre-trenching works in the portion of the pipeline within Bombay Port. Shore pull of the lines at Uran started in mid-December, 1989 and the pipe line installation continued from thereon in deeper water and was completed in May, 1990.