Revamps 2024 Issue

0.12

Proposed solution: Installation at column vendor shop

0.1

0.105

0.08

0.06

0.04

0.02

0 After

Column vendor

Internal vendor

Before

Figure 4 installation cost saving when installing trays at vendor workshop and transporting to construction site

problem resolution not only saves time and resources but also enhances overall project efficiency. The entire column and tray assembly will be transported to the construction site as a single unit, eliminating separate installations and significantly reducing the overall project duration. A streamlined process leads to cost savings. Relocating installations from the construction site to the vendor’s work- shop offers numerous advantages within the context of HSE in construction projects. This practice significantly mitigates safety vulnerabilities associated with on-site work, lead- ing to a more secure working environment for construction personnel. Workers no longer need to operate at elevated platforms, reducing the risk of falls and accidents. Avoiding the need for cranes during cartridge tray installation mini- mises potential risks such as accidents and injuries. This is particularly crucial in high-risk environments involving heavy machinery (see Figure 4 ). To achieve the proposed solution of procuring columns and trays under the same requisition, installation at the column vendor workshop and shipping to the site in installed con- dition (inside the column), Engineers India Limited (EIL) has also developed a special type of sealing with an interlocking arrangement for smooth installation and safe transportation of installed cartridge trays to site from the workshop. EIL-designed sealing arrangement: When arranging for the safe transportation of installed cartridge trays to the site from the workshop, a suitable shape and size of gasket fixed with a specially designed arrangement throughout the tray periphery is provided, ensuring proper fixing and seal- ing without any clamps for gaskets positioning and fitting. During installation, gaskets get compressed between gaps available with shell ID and tray decks, which seal the gap and restrict the liquid or vapour flow through it. Flexibility is also available from an installation point of view as gasket usually does not get damaged during installation and can be reused. Also, to cater to the small out-of-tolerance between column ID and tray OD, a range of gaskets can be used without modifying the tray or column. This arrange- ment is also useful for very small ID columns (300-450mm), where less space (active area) is available for providing sieves or valves and interrupter bar/angle due to higher space con- sumption in gasket-sealing arrangement with clamps. This ensures utilisation of the maximum active area of the tray deck

Figure 3 Collaboration between column and tray vendors

~INR 5.25 million (~$620k), including modifications and reorders. It also significantly contributed to increasing HSE risk (see Figure 2 ). To address these challenges faced on-site, installing car- tridge trays at the column manufacturer workshop is an effective solution. This may be carried out either by ordering both column and tray in the same material requisition (MR)/ request for quotation (RFQ) or with separate orders to tray and column vendors. Table 1 summarises the pros and cons of the proposed solutions for both cases. The second proposed solution, single point vendor respon- sibility for column and tray under the same RFQ and instal- lation at the workshop, ensures compatibility and facilitates seamless coordination between both vendors. Trays will be fabricated after rolling of the column shell. This strategic sequencing ensures that the column’s ID and tolerances are readily available. Upon fabrication, the tray vendor will trans- fer the trays to the column vendor workshop. Any necessary modifications can be promptly addressed at the column ven- dor workshop, leveraging existing workshop facilities and expertise. Finally, cartridge trays are installed at the column vendor workshop under the supervision of both the column and tray vendor (see Figure 3 ). Moreover, establishing communication channels between the trays and column vendors can identify and resolve any issues or discrepancies early in the process. This pro- active approach minimises the likelihood of total scrap- page due to unsuitability or defects in the materials. Early

Revamps 2024