Project Overview

A 400-foot-long pipe rack was inspected and found to have many structural deficiencies. The problems included excessive corrosion, foundations that were undermined by frost heaving and jacking, and observations that the rack had not been constructed to industry-best practices. This pipe rack conveyed critical commodities to the plant units – high pressure steam and hydrogen, sulphuric acid, hydrogen sulphide, natural gas, ammonia, and high-voltage cables. The Client required pipe rack repairs or outright replacement without interrupting normal operations.

Piperack Replacement main Piperack Replacement first Piperack Replacement second

Scope Definition

Rally worked with the Client to develop a Design Basis Memorandum (DBM) which defined the scope for this project. The pipe rack was segregated into six sections, each with an optimized repair strategy. Sections that were salvageable were reinforced and repaired, while other segments were completely replaced. Stress analysis was carried out for the piping, and repairs were made to the underlying foundations.

Detailed Deliverables

Key project scope items included pipe rack design, a new pipe bridge rail crossing, modifications to existing steel structures, and relocation of existing facilities.

A brand-new pipe bridge spanning the existing rail tracks was engineered in the space around the existing bridge. This made new construction possible without interrupting the existing piping or electrical services. Once the new rack was carrying the load, the existing rack was dismantled in situ.

The project also corrected piles to prevent further frost heaving and jacking, added pipe shoes, and upgraded spring hanger hardware to eliminate failing supports.

All field work was successfully executed while the plant remained in operation.

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