How well do you now your pipeline?

PPSA Seminar – Aberdeen

18th November 2009

Paul Birkinshaw

The industry challenge

Choosing the right pigging options

for in-service pipelines

with little or no pigging history

‘Pigging The Unpigged’

(not the unpigabble!)

The challenge for Penspen

Penspen Integrity Have been providing of pigging related consultancy

services for more than10 years

Penspen O&M Services (GreyStar UK) Significant growth area within Penspen in the UK

Providing O&M services for onshore pipelines

Pipeline operators (our clients) with little or no knowledge or experience in pigging

Particularly UK power station gas supply pipelines

We are increasingly being asked to deliver ‘Turnkey Pigging Solutions’

Wearing the operators shoes!

We need to get to know their pipeline intimately

Gathering all the available pipeline data

Collating and carefully assessing the available data

Understand the main drivers (why are we pigging it?)

Defining the key objectives (what do have to achieve?)

Identify the key challenges and uncertainties

Identifying the major constraints

A lot to think about!

What data do we need?

As-built data:  Route maps/drawings

Site / AGI plans

P&IDs

Isometric Drawings (usually of AGI plant)

Pipebook / weld records or charts

Construction POs and related procurement documentation

What data do we need?

Operational data Current operating conditions

Historical operating conditions

Suspected or known issues (e.g. evidence of dusts / sludge in filters)

Other useful data sources:  Commissioning records (including pigging reports)

Construction reports

Third party incidents

Repair and maintenance records

Why do we need it?

Good ILI data is essential

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2c/(Rt)^0.5 (normalised defect length)

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DESIGN PRESSURE (72 percent SMYS)

HYDROTEST PRESSURE (100 percent SMYS)

Safety Margin

Repair

Rejection

Acceptance

Getting hold of the data

Review the data from proposal stage

Often limited to diameter, length, service, location

Send an initial data request (the pipeline questionnaire)

The first sign of trouble!

Getting hold of the data Follow-up with meeting and site survey

To establish what's really on site (the AGI equipment)

To find out more about the buried pipeline

Your first introduction to the clients Data Room!!

The data room!!

Getting your head around your client’s document management system can sometimes be difficult!

Preparing for an ILI operation

Preparations Confirming pigging feasibility – can you get a pig

through the line ? o check bores, bends, tees, line pipe data etc.

Verifying the operating conditions are adequate for piggingo flow rate, pressure, temperature etc.

Identifying the pipeline the necessary pipeline preparations or adaptationso access arrangements, fitting temporary traps , bridle

pipework etc.

Preparing for an ILI operation

Setting out the scope of work Defining the overall objectives

Identifying the requirements for the preparatory pigging (pig selection and sequencing of pig runs)

Choosing the right ILI services (geometry, metal loss inspection etc.)

Identifying any ancillary services required (pig tracking / location etc.)

Identifying all general site services required (manning, lifting, handling, tools, waste management etc.)

Preparing for an ILI operation

Procuring the equipment and services Preparing specifications and procurement of all prep

pigs and associated services

Preparing ILI technical and contract requirements specifications

Preparing and administering an ITT for ILI services

Performing tender evaluation (technical and commercial)

Selecting and procuring ILI services (in conjunction with client)

Preparing for an ILI operation

Executing the services at site Preparing method statements and operating

procedures

Risk assessment

Checking the serviceability of the existing pipeline equipment

Carrying out the site preparations

Provision of operators (to operate valves and run pigs)

Provision of all ancillary and general services

Carrying out preparatory pigging

Management of and supporting the ILI pigging

Provision of pig cleaning equipment and waste handling

Preparing for an ILI operation

Delivering the final results Providing a preliminary assessment based on the ILI

preliminary report)

Reviewing the pipeline inspection report

Delivering a integrity integrity assessment

Having access to reliable pipeline data for all stages of the project is essential!

Penspen approach

We start with a ‘Piggability Study’

We basically take our time to gather, properly collate and to assess all the available pipeline data before embarking on a pigging campaign

This has been found to be essential, particularly for turnkey jobs…

….even if the job looks to be straight forward!

The piggability study – the questions

Can the pipeline be pigged?

What do we know about the pipeline? As built data

Operational data

Construction / commissioning records

Operational history

What preparations (or adaptations) are required?

Serviceability of existing facilities

Adaptations (fitting temporary traps etc.)

Adjustments in operating conditions

What are the operational constraints?

The piggability study – the questions

What are the notable pipeline features? Connections

Major crossings (e.g. road, rail, water)

What kind of ILI is required? To facilitate a full integrity assessment

Which pig(s) to start with? Proving and gauging

How much cleaning?

How much contingency?

The piggability assessment provides..

A piggability assessment report

For the client and ourselves

An assessment summary An overview of the issues

A pipeline data file (collating all the relevant data)

For the client and to disseminate within the project team

The data drives everything!

Piggability study – key outputs

Confirm pigging feasibility (hopefully!)

Identify any necessary pipeline adaptations and modifications

Identify any areas of uncertainty for further investigation

Scope out the appropriate preparatory pigging operations and related tasks

Collate key technical data for pig selection and specification

Identify the key requirements for ILI pigging (the ILI service requirements specification)

Piggability study – outputs

Identify any appropriate ancillary services (e.g. pig tracking)

Develop a project plan for the operations

Provide key input data for the development of method statements and reliable operational procedures (none routine procedure)

Provide a sound basis for risk assessment and the development of mitigation measures

Provide valuable input data for ILI data analysis process the final integrity assessment

Power station gas supply pipelines

Owned by power station operator

Utility companies or private operators

High pressure lines Connected to NTS

With or without PRS

Continuous operation Must keep the generators

going

Often no alternative source of gas supply

Sole grid connection

Power station gas supply pipelines

No operational pigging

No permanent pigging facilities

Usually facility to install temporary traps

Limited operator knowledge

Not core business / O&M contracted out

Lack of confidence in (or availability of) pipeline as-built records

24” example (turnkey project)

HDD Crossing800m / 19.1mm pipe / 16m deep

High Gas Flows (3.5 m/s)

Doubts about final routing (fabricated bends?)

No records of any commissioning pigging

Concerns about debris (dust / liquids build up)

Daily revenue from pipeline £1.2M!

Horizontal Directional Drilling (HDD)

24” Receive pipework

24” example

HDD Crossing800m / 19.1mm pipe / 16m deep

High Gas Flows (3.5 m/s)

Doubts about final routingFabricated bens?)

No records of any commissioning pigging

Concerns about debris (dust / liquids build up)

Cautious progressive approach to pigging / early geometry pig run (+ bend detection)

Concerns reduced through further investigations

Key input to requirements specification (ILI tool capabilities

After the ILI pig run…

Forged Bends

Pipe Joints

Using the ILI mapping data

Piggability study – benefits

Confirming the adequacy of all launch and receive facilities

Pig trap requirements

Access issues

Confirming the arrangement s of the existing AGI pipework

Quantify the full range of pipe thickness and bores

Optimum sizing of pigs and sealing elements

ILI service specifications

Piggability study – benefits

Identifying the location and configuration of all major infrastructure crossings locations

For risk management and emergency response planning

Identification of significant geometrical features including known minimum bend radius

For correct pig selection,

Pig configurations

Sequencing of pig runs (pipeline proving)

Piggability study – benefits

Identification of potential debris sources and contaminants

For correct pig selection,

Evaluating risk to downstream plant and for

Preparedness at the receive end (pig cleaning and debris handling)

Sound procurement Getting the right equipment and service levels (quality

control)

Managing financial risk

Piggability study – benefits

Reliable planning and execution Managing risk and QHSE

Delivering effectively and to time and budget

Reliable data analysis and reporting Eliminating uncertainties in the data

Getting more out of the data

Assuring pipeline integrity

Summing up

Access to good pipeline records is key to successful pigging

Increased effectiveness Choosing the right pigs

Selecting the right ILI services

Get the most out of the results

Increased efficiency Get it right first time

Avoiding mistakes

Take out unnecessary conservatism

Reduced risk

Smart pigging requires a smart approach!