Nov 2012 | ISA

This article is from Nov 2012

Introduction

The pipeline industry in general is regulated by Pipeline & Hazardous Material Safety Administration (PHMSA). A current topic of interest is Control Room Management (CRM) regulations that have an impact on the control system such as alarm management (addressed by my peer on another page in this site). On this page we will stay focused on the SIS discussion, suggested design approach & useful industry links related to pipeline safety (see below).

Definition

For definition of Safety related operations parameter, let’s visit PHMSA FAQ A.16 from following link and inspect that in depth. (http://primis.phmsa.dot.gov/crm/faqs.htm)

A.16 What are “safety-related” operations and parameters in the CRM rule?

For purposes of Control Room Management, PHMSA considers safety-related to mean any operational factor that is necessary to maintain pipeline integrity or that could lead to the recognition of a condition that could impact the integrity of the pipeline, or a developing abnormal or emergency situation. [§§ 192.631(a) and 195.446(a)]

So key words from this definition are “maintain pipeline integrity” and “indicator of impact on pipeline integrity”. This will lead us to define safety functions for Pipeline Operations which include pump stations and tank farms.

Typical Safety Functions

1. Pressure Protection for pipeline. Examples are as follows:

a. Pressure over MCP
b. Pressure over MOP
c. Unit / Station outbound line pressure
d. Unit / Station discharge (Case) pressure
e. Station Control Valve System
f. Station VFDs for pressure regulation
g. Relief System Active indications

2. Station Protection for pump station facility. These comprise of following:

a. Strategically located ESD Push button stations
b. Block Valve System
c. Fire & Smoke detection

3. Fire & Vapor Protection for pipeline and stations

a. Strategically located Fire Detector
b. Strategically located Vapor Detector

4. Overfill Protection for Tank farms and stations. Typical examples are as follows:

a. Tank Level
b. Any containment Level such as Pump Seal; Ground Sump; Relief Tank etc

5. Pipeline Protection which will include Line Balance using custody transfer flow meter and Leak Detection.

SIL Calculations

In an upcoming article I will take typical examples from the above listed safety functions and discuss typical control system deliverables and SIL Calculations.

Hiten Dalal, P.E., PMP of Kinder Morgan is the pipeline committee chair. He can be reached at: hiten_dalal@kindermorgan.com

Related Links