Drilling Through Copper Bus Bars

[davidrose99]

I recently spent roughly an hour drilling through copper bus bars, surely there's an easier way to do it? :ack2:

 

[123]

Busbar clamps?

 

[dcelectrical]

cutting fluid - corded high speed drill and cobalt drill bits, I n drill through RSJ's with that lot so copper should be no prob. bob.

 

[PEG]

...You must have been using a left-handed bit,and Fred Dibnahs' ratchet drill....:icon12:

 

[Engineer54]

Unless he was drilling them ''Live''!! The naughty boy!! lol!!

 

[Knobhead]

It would help to know the size of the bars and hole.

Something else to consider, if the bars are heavily loaded reducing the CSA reduces the CCC.[SUP][/SUP]

 

[Des 56]

Unless he was drilling them ''Live''!! The naughty boy!! lol!!

Now who would do such a thing lol

Then after live drilling,the mate happens by and he gets the mate to put in the final bus bar cover bolt Thats when the H+S get involved with one of their Spanish inquisitions and he gets sacked for putting the poor lads life in danger

 

[davesparks]

Use a drill bit with the point sharpened to the correct angle, drill running at the correct speed for the material, don't push too hard and use plenty of lube

 

[davesparks]

cutting fluid - corded high speed drill and cobalt drill bits, I n drill through RSJ's with that lot so copper should be no prob. bob.

You need a slow drill for efficient drilling of steel, not high speed

 

[PEG]

Electrical copper is a purer entity,than,say,a bed pan...and will require "glass" sharp bits,soluble coolant at higher concentration,and steady speed & feed rate.

Carbide or Tin-coated bits for deeper,blind and multiple drilling. The second it wanders,backs-off or loses its' edge,it will "push" or "smear"...and problems ensue...

Do not under-estimate how such a seemingly soft material can wear HSS bits,including flute sides.

As for occasional Bus-bar drilling,a standard,HSS bit,sharp,and dipped in lube,will be fine.

In my experience,99% of lads drilling problems,stem from the same two reasons.

Incorrect bit speed (mostly too fast) and persevering with dull bits,due to inability to sharpen.

A morning spent drilling hardened steel,using a Stellite bit,would make boring a bit of copper,seem fun :icon12:

 

[Knobhead]

I know it’s not practical for site work. Punched holes are far better than drilled.

 

[DPG]

Must admit I never knew copper would cause much problems for drilling. Mind you aluminium surprises people sometimes when they try to drill and tap it. Funny watching them trying to get the tap back out though once it has snapped flush with the surface of the plate Daz

 

[PEG]

I know it’s not practical for site work. Punched holes are far better than drilled.

Water laser makes a pretty enough job,but maybe the odd issue in a live bus-bar chamber...:icon12:

Hydraulic punching rigs were once on my repair list,10,000 psi power-packs...inch and a quarter of road plate - no problem...but do not be tempted to try doing the same on a piece of Kevlar matrix...stuck like King Arthurs' sword...not my best bit of R&D :conehead:

 

[jeremy]

If a hole is drilled and tapped, then studded, does this affect the CCC? I'd have thought the bolt/ stud would in effect become part of the bar, but I'm ready to be educated!

 

[Engineer54]

Now who would do such a thing lol

Then after live drilling,the mate happens by and he gets the mate to put in the final bus bar cover bolt Thats when the H+S get involved with one of their Spanish inquisitions and he gets sacked for putting the poor lads life in danger

With the company that i did my training with, it was basically an expected an practice, when other methods had been ruled out, but that was then, and this is now!!!
As has been pointed out on here on quite a few occasions now, many of us old dinosaurs were methodically taught how to work safely with live working. In our case the company had all the necessary safety equipment including the most comprehensive set of fully insulated hand tools i have ever seen before or since!! It's something that has from what i can make of it, virtually disappeared now....

 

[GB.Kayak]

Water laser makes a pretty enough job,but maybe the odd issue in a live bus-bar chamber...:icon12:

Hydraulic punching rigs were once on my repair list,10,000 psi power-packs...inch and a quarter of road plate - no problem...but do not be tempted to try doing the same on a piece of Kevlar matrix...stuck like King Arthurs' sword...not my best bit of R&D :conehead:

What is a 'water laser'? I have only come across water jet OR laser cutting ... though often companies who do one also do the other! I really don't want to be too pedantic ... I just can't help it ... 'Kevlar matrix' is an interesting term. The Kevlar in a product made from Kevlar is the fibre reinforcement which is surrounded by a 'matrix' that is generally some form of thermoset plastic or thermoplastic material.

 

[PEG]

What is a 'water laser'? I have only come across water jet OR laser cutting ... though often companies who do one also do the other! I really don't want to be too pedantic ... I just can't help it ... 'Kevlar matrix' is an interesting term. The Kevlar in a product made from Kevlar is the fibre reinforcement which is surrounded by a 'matrix' that is generally some form of thermoset plastic or thermoplastic material.

No,your right,it deserves qualifying ..."water-laser" is a common enough generic term for HPW cutting equipment,some water only,the larger rigs use a range of "introduced" or injected cutting mediums,and are used in the gas/petro-chemical industries,for their obvious benefits.

The reference to "Kevlar matrix",was for a product described exactly as so,which formed the inner lining,on a chamber used in ballistic testing,where,basically,bullets could be filmed impacting various materials. It was fairly old,and i had it described,to me,as a "super" bullet proof material.

Over the years,out of boredom/interest,i had "tested"" it brutally,and wondered one day,what carnage a large,hole-punch would inflict....

It got part way through its' cycle,and jammed. Properly.

It was an afternoon out of my life,to press it back out,and the forces involved,were considerable,at one point i had a piece of copper,as spacer for the punch,and witnessed it "oozing" from the edges like caramel :icon12:

 

[Knobhead]

If a hole is drilled and tapped, then studded, does this affect the CCC? I'd have thought the bolt/ stud would in effect become part of the bar, but I'm ready to be educated!

We avoided drilling large holes in bars if we could but it wasn’t always possible to get lugs with multi-hole fixings. What we would do is put a copper compensating plate on the side of the lug with a steel pressure plate on the otherside of the busbar.
The steel backing plate was a trick I pinched from GE switchgear. If you look in any GE System 4 fuse switches there is an anodised steel pressure plate between the fuse connections and the securing nuts.