Conventional Steel Cutting

Question 1

what are some target materials

Answer 1

high carbon- metal working dies

alloy- gears, shafts, tools

cast iron- railroad and pipes, very brittle

nickel- not suitable to be cut by con. steel, adv steel techniques

Question 2

what are some explosive factors

Answer 2

type, size and placement are important, tamping is rarely practical

Question 3

what type of explosives are best suited for steel cutting

Answer 3

plastic and sheet explosives

Question 4

what are the key factors for charge placement for conventional steel cutting

Answer 4

charge to target contact

width of charge is 1-3 times its thickness

Question 5

what is the conventional steel cutting formula

Answer 5

P=3/8” x Area

or

P=.375 x area

Question 6

describe P=D formula

Answer 6

over 0”, not over 1”, use 1lb

over 1”, not over 2” use 2lb

over 2”, not over 3”, P=D squared

over3” split and stagger charge

used for cutting mild steel, chains, bar etc

Question 7

what is the P=D(squared) formula used for

Answer 7

used for high carbon or alloy steel

or

steel bars, rods, chains and cables over 2”

Question 8

what are the rules of cutting railroad tracks

Answer 8

railroads less than 5” high use 1/2 pound TNT

rails 5” or higher use 1 pound TNT

for switches and crossovers use use 1 pound TNT

for frogs use 2 pounds

Question 9

what are the three types of advanced steel cutting charges

Answer 9

ribbon

saddle

diamond

Question 10

how much does molding M112 reduce the RE

Answer 10

as much as 25%

Question 11

what is the ribbon charge calculation

Answer 11

charge thickness = 1/2 the thickness of the target or minimum of 1/2”

charge width = 3 times charges thickness

charge length = desired length of cut

then calculate charge volume (CV)

thickness x width x length

Question 12

for ribbon and c shaped ribbon charges what is the minimum charge thickness

Answer 12

1/2”

Question 13

how much explosives must be around your prime i.e. blasting cap/knot

Answer 13

1/2” surrounding primer

Question 14

what calculation do you use for a c shaped ribbon

Answer 14

same as ribbon

Question 15

what kind of cutting method does the saddle charge use

Answer 15

cross fracture cutting method

Question 16

what is the saddle charge used for and how thick is it

Answer 16

used for mild steel bars, round square or rectangular up to 8” thick

charge is 1” thick

Question 17

where do you prime a saddle charge

Answer 17

at the apex of long axis

Question 18

what is the formula for saddle charge

Answer 18

charge thickness = 1”

charge base = 1/2 the circumference of the target

long axis of charge = the circumference of target

Question 19

how do you get the volume of charge for saddle charge

Answer 19

VC = base(squared) = B squared

Question 20

what method of cutting does the diamond charge use

Answer 20

stress waive method

Question 21

what are diamond charges used for

Answer 21

high carbon or alloy steel up to 8” diameter

Question 22

what formula do you use for diamond

Answer 22

same as saddle