Turnaround Planning

Chapter from the Hydroprocessing Operations Guide.

HYDROPROCESSING TURNAROUND PLANNING

Turnaround Scope Checklist

Category	Scope Item	Frequency	Duration	Critical Path?	Parallel Activities	Notes
Reactor	Catalyst changeout	Every 2-5 years	10-20 days	YES — longest single activity	Exchanger cleaning, vessel inspection	Plan early: catalyst ordering, dense loading crew
Reactor	Reactor entry & inspection	Every turnaround	3-5 days (per reactor)	Yes if catalyst change	Thermocouple replacement	Confined space, H2S monitoring required
Reactor	Distributor tray inspection/repair	Every turnaround	2-3 days	If catalyst is out	Skin TC installation	Critical for bed temperature distribution
Exchangers	Bundle pull & cleaning	Every turnaround	5-10 days	Sometimes (large E/E)	Reactor work, piping inspection	Plan crane access, bundle storage area
Heater	Tube inspection (UT, IRIS)	Every turnaround	5-7 days	Rarely (parallel to reactor)	Burner maintenance, refractory repair	Schedule heater work while reactor is open
Piping	Inspection & repair	Every turnaround	Varies	Rarely	Other inspection activities	Focus on high-consequence circuits
Vessels	Separator, drum inspection	Every turnaround	2-3 days each	No (parallel work)	Piping tie-ins, valve replacement	Internals inspection, corrosion mapping
Instruments	Loop checks, valve testing	Pre-startup	5-10 days	Yes — cannot start without	Electrical checks, motor runs	Start loop checks ASAP after mechanical completion
Rotating Equipment	Compressor overhaul	2-5 year interval	10-15 days	Sometimes (recycle comp)	Alignment checks, coupling replacement	Long-lead spare parts ordering critical

Pre-Turnaround Readiness Checklist

6 Months Before:
• Catalyst order placed and delivery confirmed
• Dense loading contractor contracted
• Scope of work finalized with inspection team
• Long-lead spare parts ordered (compressor parts, special valves)
• Safety plan and permit procedures reviewed

3 Months Before:
• Detailed schedule (Level 3 minimum) issued
• All materials on site or delivery dates confirmed
• Contractor mobilization plan finalized
• Equipment blind list prepared
• Pre-shutdown sampling and inspection complete

1 Month Before:
• Blind list walked down and verified
• All permits and safety documents reviewed
• Scaffold plan finalized
• Crane plan finalized (critical lifts identified)
• Communication plan issued (daily meetings, escalation path)

Shutdown Day:
• Controlled shutdown per operating procedure
• System depressured and cooled per catalyst vendor requirements
• Inert (N2 purge) before entry
• Blind installation per blind list
• Confined space gas testing before entry

Source: Hydroprocessing_Ops_Guide_v1.xlsx · sheet “Turnaround Planning”

© 2026 Inflection Point Engineering, LLC. All rights reserved. The content of this page — including calculation methods, reference data, written analysis, interactive tools, and source code — is the intellectual property of Inflection Point Engineering, LLC and is protected under applicable copyright, trademark, and trade secret laws. Unauthorized reproduction, redistribution, modification, or derivative use in whole or in part is prohibited without prior written consent.

Disclaimer. This material is provided for informational and educational purposes only and does not constitute professional engineering advice. Calculations, reference data, and methodologies are based on published standards and accepted engineering practice but are not a substitute for engineering judgment, site-specific analysis, or review by a licensed Professional Engineer. Inflection Point Engineering, LLC makes no warranties, express or implied, regarding the accuracy, completeness, or fitness for a particular purpose of any content presented here, and shall not be liable for any direct, indirect, incidental, or consequential damages arising from its use. Users assume all risk associated with applying this content to real-world design, operations, or decisions.