Godrej Process Equipment Division (PED) is a leader in manufacturing static Process Equipment for process industries. Godrej Process Equipment manufactures the entire range of process equipment for end-users in core industry segments like Oil & Gas, Refineries, Petrochemicals, Fertilizers, Power, Water, Chemicals and Pharmaceuticals around the world. Godrej PED, is the first company in Asia to be accredited with ASME U3 Stamp certification and are one of the very few manufacturers to have supplied Pressure Vessel (hydrotested at 1500 Bar).
Dahej SEZ plot, this location with water front towards Narmada estuary was selected for further expansion. The main plant building (phase-1) comprises of 5.51 acres of ground coverage, and is built on a plot of 55.79 acres.
The Overall plant footprint is a massive Steel Structure: 363m X 160m with 29.45 m height, Phase-1 being 308.33 Mts. x 78.55 Mts. and height of 29.45mts. The factory building (Main Plant) is oriented in the North – South direction. A complex network of services and utilities are provided to support the manufacturing plant. The facility has various machines & electric operated cranes required for the manufacturing process. The plant comprises of areas like plate cutting & processing, radiography room, heavy & light machine shop, nozzle & shell preparation area, assembly & fabrication areas & hydro testing areas. The master plan prepared has various ancillary buildings supporting the manufacturing plant with the required infrastructure. The plant now comprises of Phase -1 of the project, which is of Main Plant Building – (THE STEEL STRUCTURE) + Utilities serving the main plant.
The Main Plant is a Steel Structure above plinth & RCC structure below plinth level. The total consumption of structural steel is about 5500 metric ton in the first Phase. The Building comprises of multi span, single storied PEB building. It comprises of double girder with various crane capacities ranging from 50 -150 tons & 300 tons in future spans. The size of the Plant building in Phase-1is 308.33 Mts. x 78.55 Mts. and height of 29.45mts. The Building is divided width wise into 3 bays (A to D) & Length Wise into 39 Grids. Additional 3 bays (D to G) 81 Mts are planned in future.
The proposed structures are analyzed and designed as per IS800 and IS456 to sustain the anticipated load for mean probable safe life of 50 years. The sub-structure is mainly on friction and/or end-bearing piles, as adequate soil bearing capacity was not available at shallow excavation levels. The plant is optimized as steel portal with RCC pedestals resting on pile caps and pile foundation to suit specific ground conditions.
Dahej is in seismic zone 3 as per IS 1893. For the seismic detailing the capacity design concept similar to that developed and prescribed in chapter 12 of IS 800-2007 have been adopted. The structure can withstand Seismic loads as per Zone III with a zone factor of 0.16, an importance factor of 1.75 and in compliance with Special Moment Resistant Frame norms. Building is designed including the provisions of Chapter 12 : IS 800 : 2007 & is done considering Plastic Sections. Most of the Steel Buildings are done using Semi- Compacted Sections and exclude the provisions of Chapter 12.
Due to the proximity to the sea and exposure to salt-laden moisture in air, and possibility of presence of chlorides in the moisture a minimum thickness of 6mm has been considered for primary members with design corrosion allowance of 1.5mm. Wherever Cold form section is used; the minimum thickness was 2.0 mm. The surface treatment of structural steel needed additional focus considering the harsh environment. Painting is done with Epoxy Paint which is High Alumina Volume Solid Paint having good anti- corrosive proprieties giving longer maintenance-free life. Butler system of TBSL was used for the roofing component, with pre-coated 0.75 TCT galvalume Tata Bluescope sheeting.
Construction & Logistic considerations
The main construction challenge for structural steel was the fabrication, transportation and installation of the 10 -18 mts. high columns, and the 25m to 30m portal rafters above the columns. Additionally, the crane girders had to be installed on column brackets ensuring proper alignment and levels.
The Heavy Engineering Plant at Dahej, has been a success with involvement and collaborative working of all stakeholders involved in the project. The change from a conventional truss, to a PEB structure, after close interactions and detailed reviews with all the stakeholders at conceptual stage. This change brought in advantages in the execution of the project, with better quality, safety and timelines, including reducing the height of the structure, which brought in savings. We ensured execution of the project was effective and efficient to meet the stakeholder’s expectations without compromising on the values of Godrej like safety, integrity, and environment. M30 Triple Blend Concrete (Cement+ GGBFS+ Fly ash) was used, for long term structure durability, which also helped in reduced carbon footprint. The Project execution was completed with 4 million safe working hours.
Cyrus Shroff, Project Head,
Godrej & Boyce Mfg. Co. Ltd (Godrej Construction)
Challenges Faced & Resolved
While going through the discussions with contractors, fabricators during pre-execution phase it was identified that fabricating and erecting conventional Truss (2.5m X 0.6m) would be difficult. Considering the safety and quality aspect being a major factor into the thought process, after numerous brainstorming sessions, involving all relevant stakeholders the entire structure was redesigned as Prefabricated Plate Girders with bolted connections. These Design revisions in structural sections permitted us to reduce the height of the Structure. Plate girder sections of 1.0m depth against existing section of open web truss of 2.5 m depth, enabled us to restrict the height to <30 m.
R S Mandrekar & Associates were appointed as the Proof Checking Consultants to verify the Consultants Design. The dedicated Godrej Project Team & PMC Cushman & Wakefield ensured that all works were done with 100 % Safety & Quality and the project was completed with more than 4 Million Safe Working hours. The Project has a Zero Accident record. The Result is a Project where almost every International Client who has visited the facility for evaluation has appreciated the facility and given positive response.
Fall protection system installed on the roof, is one of the best in class (Lathway Fall protection system). The Nylon sky web which is patented product of TBSL is installed for complete length and breadth of the roof for additional safety. Structural Steel doglegged staircase are installed for accessing roof height of 29.45, and internally for gantry and crane access, considering all the ergonomics and safety of people. Service platforms with railing on both side of gantry girders for safety in maintenance and servicing of cranes is also installed.
Client/Owner: Godrej & Boyce Manufacturing Co. Ltd (Process Equipment Division)
Architect & Structural Designer: IPS-Mehtalia Pvt Ltd
Peer Reviewer: R. S. Mandrekar & Assoc.
PMC: Cushman & Wakefield India Pvt Ltd
Soil & Material Testing (NABL): Geostruct Engineering Services
Steel Fabricator & Erection: JSSL (JSW Severfield Structures Ltd)
Roofing: TBSL Butler System
Steel Tonnage: 5500 MT
Civil Contractor: DCPL (Desai Construction Pvt. Ltd.)
Piling Contractor: KELLER Ground Engineering
Status : Phase-1 Completed