Something about the Gulf spill that bugs me...

Date 06-16-2010 03:15

In the tool & die shop We ground hardened steel with diamond products and it worked fine.

We dressed resin bonded diamond wheels to a concave radius with soft steel wire.

By RonG

Date 06-16-2010 05:12

I would be willing to bet some one mis-stated information giving to them.

Diamond grinding wheels are not very effective on less than RC50 hardness, space bewteen little Diamonds get plugged with soft material. A grinding wheel must continuously erode away as it cuts to keep fresh grit in contact with the work (self sharpen). That would not be the case with a Diamond wheel cemented to a steel disc. Big difference between cutting and grinding. I can't imagine the cost of a saw blade with Diamonds for teeth but stranger things exist.

Tungsten/Carbide is second only to a Diamond in hardness and makes great insert or cemented teeth.

By DaveBoyer (*****)

Date 06-17-2010 01:56

My guess is that if it is a diamond blade, the diamond is in a nickel matrix like on a concrete or rock saw.

By ctacker (****)

Date 06-16-2010 05:20

At that depth, I don't think the blade would get hot, I would also like to know what rpm the blade was running!

By jwright650 (*****)

Date 06-16-2010 11:37

I peeked in via the ROV camera while that cutting was being done....it looked to me like the pipe pinched the blade, like a saw log closing up on a chain saw.....if they had supported the weight of the pipe while cutting, it may not have pinched or bound the blade up in the cut.

...just my observation and two cents

By gndchuck (**)

Date 06-16-2010 15:05

I've used diamond blades a lot underwater, never had a problem with them clogging up. Think that it has to do with the metal never really get warm, water is a great heat sink. Also use diamond wire cutters for cutting the legs of platforms, they work really well. I've never used them out of the water, so I have no experience on that end.

By RonG

Date 06-16-2010 17:38 Edited 06-17-2010 13:29

Yes agreed, the the blade would not likely get hot with that much water and once it got through one side it would have plenty of lubricant.

I suppose if the Diamonds were placed in such away as to prevent them from packing material in between it would work. All the Diamond wheels I have worked with were for tool grinding and would not lend it's self to that application.

The wire cutters not being a ridged construction are self cleaning.

Do not know the wall thickness of the pipe but that might have had some influence on the reason for a Diamond wheel. Plus I belive I heard the pipe was around 20" OD. That would take a pretty good sized blade to slice straight through (if thats how they did it). The SFM at the OD of the Blade could get to be a big number at a realitively low RPM.

By PlasmaHead2 (***)

Date 06-17-2010 21:09

Thank you all for the replies, underwater is a diffrent world from dry land I take it.

By Cumminsguy71 (*****)

Date 06-17-2010 22:16

I read something on an oceanography website and seems like it said around 5000 feet below sea level was 39 degrees? Down around the 12000 foot mark it was just above freezing. It said the average depth of the Gulf was 12,000ft.

By SMTatham (**)

Date 06-18-2010 13:12 Edited 06-18-2010 13:16

Ya think???? Not trying to be inflammatory but jeez man; how many people I have talked to in the last month have spouted off about this or that "well in my shop" etc; etc...............I usually say "is your shop under 5,000' of cold water?" It requires a whole 'nuther body of knowledge, experience, and critical thinking skills to work in those conditions.