A Boring Question

[aniken]

Genuine question, so no hijacking (until the question is answered).

Assuming everything is set up beforehand, and ground conditions are the same, what would be quicker (in terms of metres per day completed)?

1. to bore a 375mm hole 450m; or

2. to excavate a 1.5 metre deep x 1 metre wide trench over the same distance.

[phantomchic]

ask KT that's his thing now

isn't it

shazzy

[Mr X]

Hii aniken.This is a horizontal borer with a pipe feed attached?As opposed to digging a trench and laying the pipe in it?Sewer main perhaps?

Had a contract repairing lansdcape damage for a civil engineering company putting in sewerage mains(converting from septic tanks) across peoples backyards.They had a horizontal borer they used when they absolutely could not trench with a JCB.Trenching is slower- ie excavate,layer of packing sand,two men in the trench fitting pipe,check falls and then backfill.

Horizontal borer is quicker,much quicker.I recall a run of 250 metres done in maybe 4 hours in plasticy clay.Horizontal borer is very expensive though and the pipe has to be made up in advance- ie plastic welded sections so that the whole length is ready to go.

I'd ask my mate who's a supervisor with the company(jobs for the boys ) but he's in NZ atm. Borer- quicker but dearer.

p.s.Rock with a trench can be got at with a rock breaker whereas the borer can be stopped by rock and has to be re-routed.

[ktford]

Mr Aniken,

a HDD (Horizontal Directional Drill,) that can pull a 450m shot of that length is quite a large rig, it may cost upwards of $100,000.oo. It is a much larger rig than ours. I will get you a ball park price and go further with the help of pipe prices if you tell me what pipe is required. If it is a gradient sewer job then it is dearer and slower. Our rig could complete the job if it can be done over three seperate shots of 150m ish.

To increase the hole to a size of 350mm is easy, only made hard if the ground is sand or rock.

As with any HDD job existing underground services is a big issue and takes some time to locate and pothole any that will be close to the intended bore path so they can be made visible.

I could provide you with someone able to do it in a single shot if you need so let me know when ready.

[mk11tute]

Definatly trenching would be cheaper and probably very little difference in time, as long as you have room for a suitable excavator!!

[mickq]

Use dynamite. Would take about 3/100ths of a second.

Boring holes with a machine is for pansies.

[aniken]

Mr Aniken,

a HDD (Horizontal Directional Drill,) that can pull a 450m shot of that length is quite a large rig, it may cost upwards of $100,000.oo. It is a much larger rig than ours. I will get you a ball park price and go further with the help of pipe prices if you tell me what pipe is required. If it is a gradient sewer job then it is dearer and slower. Our rig could complete the job if it can be done over three seperate shots of 150m ish.

To increase the hole to a size of 350mm is easy, only made hard if the ground is sand or rock.

As with any HDD job existing underground services is a big issue and takes some time to locate and pothole any that will be close to the intended bore path so they can be made visible.

I could provide you with someone able to do it in a single shot if you need so let me know when ready.

Estimates are based on two shots - 250m and 200m, 530mm dia bore through sandstone. A 375mm dia pipe will be inserted into the hole. Its a pressurised sewer main. Assumed productivity is 17m/day. Not my project, just helping out someone with a bit of spreadsheet cost modelling. Was interested to know whether trenching would be faster or slower than that, but all the engineers are on holidays. The costs I have seem to assume trenching would be about 40m/day (1m top soil and about 0.5m rock)

[aniken]

Use dynamite. Would take about 3/100ths of a second.

Boring holes with a machine is for pansies.

Blowing up a few roads and adjacent houses may cause a few PR issues (), but I'll pass on the suggestion to our planners...

[ducatijb]

Using dynamite might be a good way to meet the neighbours Ani..

Can we hijack this thread now???

[tab]

Sounds like a plan.