Wednesday, March 30, 2011

Week 8 - Cable Jointing - North Parade lateral spread, QE2 Drive consolidation, Philpotts Rd consolidation, Pages Rd.





Work log:


Monday 21st March: Worked at North Parade, Shirley to repair a low voltage XLPE attached to a bridge for a private right-of-way that had been severely bent (but still operating ok, amazingly!) by the riverbanks 'slumping' in the earthquake 22nd Feburary.

Slumping bending the low voltage XLPE

Steve showing off the bent section

Tuesday 22nd: QEII Drive near Marshlands Rd roundabout, XLPE-XLPE 11kV joint, network consolidation.




Wednesday 23rd: Philpotts Rd near QEII Drive, XLPE 11kV termination into kiosk for network consolidation.

Tightening 11kV terminations in kiosk
Thursday 24th: Philpotts Rd again, more kiosk terminations and XLPE-PILCA joint.

Finished kiosk terminations

Friday 25th: Pages Road near bridge, PILCA-XLPE-PILCA faulty 11kV cable replacement.

These rings are the modern alternative to lead wiping.
Liquefaction causes the building to sink, pulling overhead connections off.

Riverbank 'slumping', causing the buildings to come away from the car park.


Analysis: Cable jointers' specific tools


As with all trades, cable jointing carries with it specific tools for specific purposes. For Connetics jointers, there are tools suited to PILCA (paper insulated lead covered armoured) cables as well as modern XLPE plastic insulated cables. One advantage of having jointers from all over the country here is that we can see what tools are being used elsewhere in similar situations. For example, Northpower use heavy-duty remote controlled hydraulic cutters, which cut, obviously, but also replace spiking guns.

Connetics has observed these other tools and purchased new ones to allow more efficient operation for the jointers, such as reciprocating saws.

The cable jointers' tool box is interesting, particularly from an industrial electricians' point of view.. lots of knives, cutters and crimpers are apparent. A selection of tools are shown below.


Jeff's toolbox - All in immaculate condition. He sets a great example.


Nice new reciprocating saw. Used to cut cables and has replaced the good old hacksaw. The hacksaw is still used for cutting steel armour on PILCA cables.

Discussed earlier, the precision stripping tools for XLPE and the semiconductor layer. They're inside a wooden stool used to prop cables up above the mud in the bottom of the hole. Water seriously compromises the integrity of joints.

The 'rattler', or more formally, the impact driver is used only for shear bolts.

Car jack stands for holding the cable off the ground also.

Hook knife



Core cutter


Stripping knife - No two are the same and the jointers' all have their own favourite ones!


Outer insulation double purpose knife

Insulation stripping knife

New technology.. kevlar string used to cut plastic insulation without 'nicking' internal neutral screen conductors

Squarehead pliers designated by Tyco to be used to remove semiconductor layer.

Large crimper

Battery hydraulic crimper
 As with all trades, maintenance of tools is paramount. Knives must be kept sharp, tools must perform correctly and be clean. Dirt or poor cuts on cables reduces the effectiveness of joints and lifetime, particularly on higher voltage cables.



Analysis: What makes a good cable jointer?


As an 'outsider', it has been interesting to see the psyche of the cable jointer and what 'makes them tick'. Particularly more so with the visiting jointers from other parts of the country. It's almost humourous how easily all these guys 'click'. Even the Christchurch jointers are noticing this! They refer to themselves as a 'breed', which is correct! Whare, a very professional and experienced jointer from Northland, expressed to me that he was really happy to see the young guys were the same as he and his colleagues once were also. The jointers who are all here have picked up a catchphrase coined by Steve Bright; "That's how WE roll"!

As an aside, I had the great privilege to be invited to a BBQ at Blue Skies in Kaiapoi organised by the Northpower and Vector jointers, and had a fantastic time!


"That's how WE roll!"
The first attribute every cable jointer will tell you is the most important is that they MUST be a team player. Trust and reliability are important to all jointers, and if those attributes are not apparent, then the team will not perform efficiently or optimally. All crews work in twos, and are almost psychic in their teamwork.

The next attributes would be pride in your work and good workmanship. A joint must be done 'right first time', particularly when working under pressure where things can be forgotten. Joint kits are not cheap and if one step is missed, the entire day or job can be wasted. I like to refer to joints as 'mechanical works of art'. I personally have done thousands of electrical terminations, and understand the quality of a good termination can be life-saving. In the cable jointers' world, lives and economies depend on the quality of the joints.

Lastly, flexibility. There are numerous challenges that cable jointers need to face, from weather to earthquakes (!), to rubberneckers, bugs, rapidly rising water tables, road access, and numerous other issues. Jointers need to be able to 'think on their feet' and find solutions, quickly.


Teaching ideas: Practical demonstration/ formative and summative assessment


There's no way I will become a Master jointer in 2 months, so CPIT will be organising jointers to come in and demonstrate jointing to students. I have identified several individuals we could approach as good educators, and assessors also. With kits being so expensive, multiple summative resits are not going to be an option. On-job summative assessment will have to be used, and possibly video evidence submitted from some students. I will video these demonstrations and use them in moodle for future students to watch and learn from. I'll be asking nicely for a decent digital video camera when I get back..! Flexibility in tutoring, as on the job is going to have to be a quality I as a tutor will need.

And that's it! Week 8 over.. Next week will be my last week in jointing, and hopefully I'll see some 66kV repair on Fitzgerald Ave.

Tuesday, March 22, 2011

Weeks 4-7: The February 22nd 2011 M6.3 earthquake and the start of the repair of the Christchurch distribution network.



   


This post covers the week of the Christchurch Magnitude 6.3 earthquake and following to Friday the 18th March, the Memorial day.

Work log:

Monday 21st: Worked with Reece at Nunweek park hockey park terminating 11kV XLPE into a kiosk.

Tuesday 22nd: Attempted to finish the kiosk with Reece. Job abandoned for technical reasons. Mag 6.3 Quake hit at 12:51pm.

Wednesday 23rd February - Monday 7th March - No work - Quake recovery.

Monday 7th: Averill St 11kV quake damaged PILCA-XLPE -PILCA repair with Steve.

The post-22 Feb quake 'job desk' at Connetics

Connetics and associated supply industry workers at a promotional BBQ breakfast

My first quake casualty-11kV previously joined cable in sewer-filled hole.. nice.
Faulty quake-bent 11kV PILCA cable, River Road.
Steve jointing 11kV Averill St with the hard case boys from Transfield, T and Peachy.

Tuesday 8th: Palmers Road 11kV severe quake damaged PILCA-XLPE-PILCA-XLPE-PILCA with Steve

The cable testing trailer display.. gives estimates in meters how far along the cable is faulting. Flash piece of machinery.
Steve the test tech placing clamps on the cable under test

Quake-kinked PILCA 11kV cable

My XLPE 'half a joint' with Steve!

Wednesday 9th: Palmers Road same as previous day

The locals are fed up.

3x quake-kinked 11kV cables. The final solution was to abandon multiple joins and run a new cable.
Thursday 10th: Gayhurst Road 11kV PILCA-XLPE-PILCA with Steve

Friday 11th: Bridge Street and Estuary Road 2x joins 11kV PILCA-XLPE-PILCA with Steve

Bridge St 11kV from Bromley Substation. Note riverbank 'slumping' above Steve (which caused the fault), who is using his nice new sabresaw to cut..!
The New Brighton Substation 33kV transformers and control building that sank 2m due to liquefaction.

The Pleasant Point yacht club slumping damage

The Bridge St bridge slumping damage. We received a visit from structural engineers.
Monday 14th: Inverness St 400V Neutral screen T repairs with Steve and Robbie

Tuesday 15th: Landsdowne Terrace 400V boundary box and neutral screen repairs with Steve and Robbie and the 'Northland boys'.

Boundary box safety tagged by the 'test room' team.

The damage to the road, which caused the damage to the cables. We measured the fissure depth at 2.4 metres.


Wednesday 16th: Santa Rosa Avenue, Mt Pleasant 400V quake damaged Tees.

The boys in the Tee hole while demolition men remove the adjacent house's chimney.
Tee under preparation
Finished Tee with 'quake strain loop'.
A typical example of a Mt. Pleasant house. They got a hiding.
Marine Parade red-stickered house. Sickening.

Thursdsay 17th: Cnr Pages Rd and Anzac Dr 11kV PILCA-XLPE-PILCA quake fault repair

The quake-damaged PILCA (Note steel and lead armoured) cable. The trunking in the broken concrete behind houses the faulty 66kV cable that was replaced by an overhead line is super-record time. 

Robbie with the finished product.
Friday 18th: Quake memorial day.

Personal statement

Firstly, I'd like to express my absolute sorrow for all of the victims of the Christchurch aftershock earthquake that struck at 12:51pm on 22nd February 2011. I refer to the victims as 'the unlucky ones', the reason being I believe it was pure luck that determined who died or who survived the earthquake. My wife Emma and I were just leaving a car park on Bedford row just around the corner from the CTV building when the quake struck. I believe I now truly know the meaning of terrifying. We were extremely lucky that we were in the shadow of the newly constructed IRD building, which had been built extremely sturdily and protected us.

The sights we witnessed on our flight out of the city centre will live with me forever. Our house received further foundation damage. Luckily the structure seems intact. In the two weeks following the quake we had no power for a week, and no water or sewer for 3 days. We did volunteering work in the community to help people out (as you do). I was extremely humbled by how New Zealand and the World came to our rescue, and how the community rallied to help each other, even in our wee street.

I was going to do an analysis of heatshrink vs. cold shrink, among other individual items these weeks, but instead I would like to pay tribute to the heroes I am having the extreme privilege of working with.

Starting at the top, the management and administration staff of Connetics have shown fantastic resilience, and superb organisational ability to coordinate the reconnection of power in our broken city so rapidly. Employees and visiting employees from Vector, Transfield, and several other power supply companies have been given motivational talks, BBQ breakfasts, psychology talks, and even stand-up comedy! These examples of exceptional leadership, combined with site visits of the repairs being done, have led me to make the comments I have. I have been watching in awe of the performance.

The 'coalface' workers simply keep going. Quality and unwavering performance in the face of the biggest natural disaster to strike this country has been the hallmark of these workers. Yes, they are paid to do the job, but many carried on working with broken homes that had no water, power or sewer.

All of this is combined with nightly 'wake-up call' aftershocks, which get the adrenalin going and makes getting back to sleep difficult, radical future earthquake predictions from inconsiderate attention-seekers, scumbag looters, and the ever-present threat of the Alpine fault or more unknown quake sources make for difficult living, let alone working.

I salute all power workers, all Governmental workers, USAR legends, Police (Kiwi and Aussie), core infrastructure workers, health workers, engineers, student army members, Red Cross, everybody who cared and donated, and finally, the awesome Christchurch people.

Rise up, Christchurch.








Tuesday, March 15, 2011

Week 3 - Cable Jointing - Halswell Junction Road, Tradefit, Timaru 33kV

Far out time's going fast on this ASL (academic study leave)! Week 3 over!

This week's log:


  • Monday: Halswell Junction Road with Jamie. 11kV XLPE-HDPE (high density polyethylene), spiked. 
Good 'spike'.. right through!


  • Tuesday: Orion EAC (entry approval certificate) course in the morning at CPIT Tradefit, afternoon Ensors Road with CJ and Nick to break into a 11kV PILCA with two XLPE for a kiosk. 
Steve shows CPIT students the inside of a kiosk





  • Wednesday: Timaru with John, Terry, and Mark to do 33kV 1200mm2 3x single core XLPE. 
Ends prepared for joining

  • Thursday: CPIT tradefit sub terminations with Steve. 
  • Friday: Halswell Junction Road 11kV XLPE-PILCA with Steve 







Analysis: 


33,000 volt joining in Timaru


On Wednesday I travelled to Timaru to see John, Terry and Mark joining 33kV cables for Alpine Energy. Cables come in drums of (?) length, and need to be joined the length of the full (?) run to a new substation.

The joining is done deep underground, under all other services. Connetics use a open-bottomed container as weatherproofing and for protection of the jointers.

The 'joining container'



The cables are 3x single 1200mm2 aluminium with neutral screen XLPE and MDPE (medium density polyethylene). Alpine's specification was to use crimp joiners rather than the newer 'shear bolt' joiners. 

Cable description on side

1200mm2 aluminium 33kV cable


Both ends of the 33kV cable are stripped and prepared with the minimum wastage possible. They are measured and aligned for joining.

Stripped and ready for joining



The joint is performed using a large hydraulic crimper, which is a very flash and expensive piece of equipment!  The cable is stripped back to measurements specified by the joint manufacturer, with the usual extra care for the semiconductor layer. Correct measurements are crucial to this operation, with no room for error (no pressure!).




Crimping done


John would like to lay claim to his 'John's jack system', which ensures the crimper is always at the correct height using a heavy duty hydraulic vehicle jack! Brilliance!



John's jack!


John in action

Seeing John and Terry (the joiner guru!) in action was great! 


I travelled back, pausing at Highfield Road to stand on the Greendale fault, the cause of out M7.1 quake and $5,000,000,000 of damage in Canterbury. Kinda odd that Highfield Road is next to fields that have been pushed up... High.. sad I know...!


On Highfield Road, the Greendale fault line

Postscript.. NOTE: This is still before 22nd February. Post-quake coming soon.



Hazards 



The following hazards are associated with cable jointing:
  • Electricity (obviously!) in kiosks and nearby cables
  • Open flame/heat when heating cables for stripping and when heating heat shrink
  • External noise and the driver for shearbolts
  • Tools/sharp ones in particular for stripping
  • Other contractors/public (including 'rubberneckers', which there are a surprising amount of!)
  • Vehicles/heavy and diggers etc.
  • Weather wind/sun/rain
  • Dust, when windy
  • Fumes from heating pitch in PILCA cables
  • Oils on PILCA cables
  • Sharp edges
  • Holes/cave ins
  • Kiosk and sub doors
  • Dehydration
  • Lead poisoning
  • Slips
Teaching methods for hazards:
Brainstorming - drawing on previous knowledge of students
Practical (individuals or teams depending on formative or summative assessment)
Scenario work - field trip or photos/video (moodle?)
The semiconductor layer 
The semiconductor layer is a thin layer in HV cables that usually surrounds the immediate first conductor insulation layer (usually XLPE). The function of the semiconductor layer is to 'spread the charge' if the XLPE layer fails insulation-wise. Special tools are used to strip the semiconductor layer carefully and NOT damage the XLPE layer. This layer is a modern measure used on HV cables. A special 'strip tool' is used to strip the semiconductor layer nicely without damaging the XLPE layer.
Me using semiconductor layer stripper


Me stripping off semiconductor layer

Another enjoyable week!

Next time: The 'block' starting 21st February to 17th March. Apologies due to delay caused by the February 22nd Magnitude 6.3 Christchurch earthquake which devastated Christchurch and killed hundreds. RIP the 'unlucky ones'.