---
title: Ammonia Converter R-101 Temperature Excursion Incident Note
doc_type: Incident Note
tags: [R-101, TAHH-101, FV-101, PSV-101, KM1R]
summary: An ammonia converter (R-101) bed experienced a temperature excursion to 548 degC due to a feed purity upset, triggering a high-high trip and causing feed cut-off and depressurization.
---
**Date:** 17 June 2022
**Equipment:** Ammonia Converter R-101
**Bed Affected:** #2
**Event:** Temperature excursion
**Peak Temperature:** 548 degC
**Cause:** Feed purity upset
**Trip System:** TAHH-101
**Trip Setpoint:** 530 C
**Trip Action:** Cut feed via FV-101, depressurised to flare
**Catalyst:** KM1R
**Catalyst Inspection Result:** No permanent damage found

**Design Specifications (R-101)**
**Design Pressure:** 180 barg
**Design Temperature:** 500 C
**Beds:** 3, axial-radial
**PSV:** PSV-101
**PSV Setpoint:** 180 barg
**PSV Capacity:** 12,400 kg/h to flare

**Operational Guidelines**
**Ramp Pressure (Startup):** <= 5 bar/min
**Bed Inlet Temperature (Hold):** 380-420 C
**Runaway Risk Threshold:** Above 530 C

**Action Taken:** Added feed-purity interlock
**Status:** Closed
**Author:** K. Bose, HSE