Shield TBM cutter for underground tunnelling

Grade

Density

T.R.S

Hardness

Performance & application recommended

g/cm3

MPα

HRA

MK4

15.1

1800

90.0

Mainly used as small buttons for percussion bits to cut soft and medium
hard formations.

MK6

14.9

2000

90.5

For coring crowns, electric coal drill bits, coal cutting picks, oil cone bits
and scraping knife bits, usd in geological prospecting, coal mining and
oil well boring.

MK8

14.7

2400

89.7

For coring crowns, electric coal drill bits, coal cutting picks, cone drill bits
and scraping knife bits, used in geological prospecting, coal mining and
oil well boring.

MK10

14.7

2450

88.5

Mostly used as the buttons of small and mediumsized percussion bits and
as the inserts of rotary prospecting bits to cut soft and medium hard

formations.

MK15

14.6

2450

87.8

Suitable to strips, conical buttons for rotary percussion-resistant, geological prospecting buttons, cut soft and medium hard

formations.

MK20

14.4

2550

87.0

Primarily for the buttons and inserts of rotary percussion bits to cut

medium-hard and hard formations.

MK25

14.5

2600

87.5

Primarily for the buttons and inserts of rotary percussion bits to cut medium

hard
and very hard formations.

MK30

14.4

2600

87.0

Largely for the inserts and buttons of percussion bits and tricone bits to

cut medium-hard, hard, and very hard formations.

MK40

14.2

2650

86.5

Predominatly for the buttons of tricone bits and inserts of rotary percussion

bits to cut hard and vey hard formations.

MK50

14.0

2700

86.0

For oil cone drill bits, for medium soft and medium -hard rocks.

MK60

14.0

2500

87.0

Good strength and less wear resistance, for bits of rotary hammer rock

drills and heavy rock drills, for hard and very hard rocks.