ERLP Commissioning

Naomi Wyles

ASTeC

STFC Daresbury Laboratory

Overview of ERLP

Electron Gun

DC Photocathode Electron Gun

First electrons obtained in August 2006

Achievements so far

Both super conducting linac modules cooled to 2K

Synchronisation of RF and photo-injector drive laser

High power RF tests for linac module

Commissioning of terawatt laser for Compton back scattering and electro-optic bunch length diagnostic

Overview of ERLP

Gun Power Supply

Gun

Super Conducting Booster

1st (outward) Arc

2nd (return) Arc

Transfer Line

Energy Recovery Linac

Beam Dump

Commissioning Tasks

Construction of ERLP is not yet complete Commissioning has taken place in the following areas

Photoinjector laser system This was installed and commissioned prior to the gun being ready Further enhancements made after the first phase of gun

commissioning The electron gun is currently beaming into a dedicated diagnostic

beamline All radiation control systems complete

Cryogenic system has been commissioned to 2K Usually possible in parallel with construction work

RF System Buncher cavity, transverse deflecting cavity and main SC

accelerating modules are all being commissioned at present

Planning the commissioning

The electron gun is being commissioned using a dedicated diagnostic beamline Dedicated diagnostics include horizontal and vertical slits, YAG

screens, transverse deflecting cavity and an energy analyser magnet This will be removed when gun commissioning is complete

At the same time the remainder of ERLP is being constructed Lead time for the delivery of the SC linac modules was significantly

longer than anything else Problems with building and commissioning the gun

Problems in achieving XHV braze between gun ceramic and metal flanges lead to delays in gun construction

Additional problems while operating the gun led to serious delays in gun commissioning

Gun commissioning is now on the critical path Construction programme is running well

Commissioning and construction conflicts (health and safety)

Construction and commissioning have to be separated in time Construction during office hours Commissioning overnight and at weekends

This pattern means work has to be carefully controlled to avoid any conflicts Permit to Work (PtW) system (already used at Daresbury in other

areas so staff are familiar with it) Includes a Risk Assessment and a Written System of Work Not practical to cancel every permit before every commissioning shift Handover procedure has been developed

Handover procedure

ERLP has a site manager who will know what work is going on and what permits are outstanding

The handover manager is responsible for the handover procedure being followed correctly

A handover sheet must be completed Handover procedure

The site manager checks that there are no outstanding PtWs that prevent commissioning

The site and handover managers tour the accelerator area checking for people and making notes of hazards

The site manager then issues a PtW for the commissioning and releases the keys for machine operation

The Key commissioning team member then reads and signs the handover sheet

The handover sheet and PtW are kept on display and must be read by subsequent Key Commissioning team members

The handover sheet also specifies what must be done to return from commissioning to construction

Handover Sheet

Commissioning and construction conflicts (staff availability)

Most staff do not work on ERLP full time

Commissioning team are mainly accelerator physicists and technologists who work on other projects as well

Construction team are also involved in other projects, particularly the SRS which has a schedule written many months in advance

The running of the SRS has to take priority over ERLP because it is a user facility

Scheduling and Shifts

Commissioning uses a 3 shift system Shift1 – 00:00 – 08:00 Shift 2 – 08:00 – 16:00 Shift 3 – 16:00 – 00:00

Weekdays only shifts 1 and 3; construction in shift 2

Weekends/Holidays all 3 shifts used

Flexibility about when construction ends

Staff work shifts on a casual basis – average of 1 per week

Availability collected (which is expected to be ‘reasonable’) on an Excel spreadsheet

Roster produced based on this Macro sends Outlook

appointments No problems due to large pool of

people Smaller pool of people would

require fixed shifts

Commissioning team

Every beam commissioning shift requires 2 people One must be a member of the ‘Key Commissioning Team’

Responsible for leading technical work Responsible for personnel and machine safety

Key Commissioning team members only devote 30% of their time to commissioning

They undertake additional training Laser safety General Health and Safety

Second team member does not have such a large commitment to the project They are expected to be interested and enthusiastic

Training

All personnel who wish to enter the ERLP accelerator areas must have undertaken basic radiation safety training (or be accompanied at all times by someone who has)

Enforced by access control system using ID badges Commissioning team have additional training in the Personnel Safety

System Includes how to carry out a search If there was a radiation incident the SRS crew would be called and

are responsible for implementing action Key commissioning team have additional training

4 day health and safety course which is being rolled out to everyone with management or project responsibilities

Laser training – enables them to switch the laser on and off thus not requiring a laser specialist to be present at all times

Documentation

ERLP Safety Handbook Issued to all key commissioning team members and other relevant

staff Covers how safety is organised Lists those with specific safety responsibilities and what those

responsibilities are Details procedures for carrying out all kinds of work Content is presented during basic safety training

Local rules All commissioning team members must be familiar with these

Documentation ELOG

Log for recording work in shifts Fault reporting system which automatically e-mails relevant specialist ERLP Manual ERLP Manual is slowly being replaced by a Wiki-style manual This records and saves all versions Web based so can be accessed off site

Project plan This is live and enables people to see when the next commissioning

period will begin During commissioning there is a much more detailed shift by shift

plan Fine detail only added near the time

Reports These are written after the work is discussed at a weekly meeting

Communication

Meetings are held on a regular basis During construction daily meeting at 09:00 to discuss day’s work and

any conflicts with commissioning A weekly planning meeting is also held for construction issues During commissioning a daily meeting is held at 16:00 to discuss the

next 24 hours commissioning All commissioning team members who have been on shift in the last

24 hours or who are due on shift in the next 24 hours are expected to attend (except the night shift)

Weekly commissioning review takes place attended by all key commissioning team members and as many others as possible. Discusses previous week’s work and identifies reports to be written. Plans the next week’s work.

Conclusion

Successful method of simultaneous construction and commissioning Satisfies Health and Safety requirements Significant progress has been made in spite of technical difficulties

Useful Links

http://projects.astec.ac.uk/ERLPManual/index.php/Main_Page https://srdweb5.dl.ac.uk/erlp/elog/