Industrial Grade HSS Cobalt Twist Drill Bit Cobalt Coating

Industrial Grade M35 Cobalt HSS Twist Drill Bits (HSS-Co 5%) – Engineered for Stainless Steel & High-Hardness Metals

Premium M35 Cobalt Alloy (HSS-Co 5%): Offers significantly higher wear resistance and thermal stability compared to standard HSS, extending tool life by 3–5 times in abrasive materials.
135° Split Point Tip: High-performance self-centering design eliminates “walking” and the need for a center punch. It reduces thrust requirements and ensures immediate penetration into tough surfaces.
Fully Ground Process: Precision-ground flutes provide superior chip evacuation and surface finish quality, resulting in cleaner holes and better dimensional accuracy.
Amber Oxide Surface Treatment: The unique bronze finish provides enhanced lubricity, reducing friction and preventing heat buildup for smoother, faster drilling.
Industrial Strength: Hardened to HRC 65-68, these bits are capable of cutting through materials that would quickly dull or snap conventional drill bits.

Target Materials

1.Stainless Steel: SS304, SS316, 201, and other high-tensile grades.

2.Hardened Steel: Alloy steels, tool steel, and die steel.

3.Specialty Alloys: Titanium, Inconel, and high-temp alloys.

4.Heavy Duty: Cast iron, spring steel, and abrasive metals.

B2B Service & Support

Wholesale & Bulk Supply: Competitive tiered pricing for high-volume distributors and industrial users.
OEM & Custom Branding: Private label laser-marking and custom packaging options available to match your brand identity.
Fast Lead Times: Optimized supply chain with significant stock levels to ensure your production lines never stop.
Global Shipping: DDP/FOB shipping terms supported for global delivery.

Application
HSS Grade	Iron	Aluminum	Carbon Steel	Tile	Plastic	Stainless Steel
4241	YES	YES	NO	NO	YES	NO
4341	YES	YES	YES	NO	YES	YES
6542(M2)	YES	YES	YES	NO	YES	GOOD
M35 (Co 5%)	YES	YES	YES	NO	YES	VERY GOOD

DESCRIPTION OF HSS	C	W	Mo	Cr	V	Co	Si	Mn	P	S
	%	%	%	%	%	%	%	%	%	%
W4Mo3Cr4V(4341)	0.88-0.98	3.5-4.5	2.5-3.5	3.8-4.4	1.2-1.8		0.5-1.2	0.2-0.4	<=0.03	<=0.03
W6Mo5Cr4V2(M2)	0.8-0.9	5.5-6.75	4.5-5.5	3.8-4.4	1.75-2.2	–	0.2-0.4	0.2-0.4	<=0.03	<=0.03
W6Mo5Cr4V2Co5(M35)	0.9-0.95	5.5-6.5	4.5-5.5	3.8-4.4	1.75-2.2	4.5-5.5	0.2-0.4	0.2-0.4	<=0.03	<=0.03
W2Mo9Cr4V2Co8(M42)	1.05-1.15	1.15-1.85	9.0-10.0	3.5-4.25	0.95-1.25	7.75-8.75	0.15-0.65	0.15-0.4	<=0.02	<=0.025

Metric size

DIA.(mm)	OVERALL LENGTH(mm)	WORKING LENGTH(mm)
1	34	12
1.5	43	20
2	49	24
2.5	57	30
3	61	33
3.5	70	39
4	75	43
4.5	80	47
5	86	52
5.5	93	57
6	93	57
6.5	101	63
7	109	69
7.5	109	69
8	117	75
8.5	117	75
9	125	81
9.5	125	81
10	133	87
10.5	133	87
11	142	94
11.5	142	94
12	151	101
12.5	151	101
13	151	101
13.5	160	108
14	160	108
14.5	169	114
15	169	114
15.5	178	120
16	178	120
16.5	184	125
17	184	125
17.5	191	130
18	191	130
18.5	198	135
19	198	135
19.5	205	140
20	205	140

Imperial size

DIA.	OVERALL LENGTH (INCH)	WORKING LENGTH (INCH)	DIA.	OVERALL	WORKING LENGTH (INCH)	DIA.	OVERALL	WORKING LENGTH (INCH)
1/64″	3/4″	3/16″	15#	3-3/8″	2-3/16″	61#	1-/5/8″	11/16″
1/32″	1-3/8″	1/2″	16#	3-3/8″	2-3/16″	62#	1-1/2″	5/8″
3/64″	1-3/4″	3/4″	17#	3-3/8″	2-3/16″	63#	1-1/2″	5/8″
1/16″	1-7/8″	7/8″	18#	3-1/4″	2-1/8″	64#	1-1/2″	5/8″
5/64″	2″	1″	19#	3-1/4″	2-1/8″	65#	1-1/2″	5/8″
3/32″	2-1/4″	1-1/4″	20#	3-1/4″	2-1/8″	66#	1-3/8″	1/2″
7/64″	2-5/8″	1-1/2″	21#	3-1/4″	2-1/8″	67#	1-3/8″	1/2″
1/8″	2-3/4″	1-5/8″	22#	3-1/8″	2″	68#	1-3/8″	1/2″
9/64″	2-7/8″	1-3/4″	23#	3-1/8″	2”	69#	1-3/8″	1/2″
5/32″	3-1/8″	2″	24#	3-1/8″	2″	70#	1-1/4″	3/8″
11/64″	3-1/4″	2-1/8″	25#	3″	1-7/8”	71#	1-1/4″	3/8″
3/16″	3-1/2″	2-5/16″	26#	3″	1-7/8″	72#	1-1/8″	5/16″
13/64″	3-5/8″	2-7/16″	27#	3”	1-7/8″	73#	1-1/8″	5/16″
7/32″	3-3/4″	2-1/2″	28#	2-7/8″	1-3/4″	74#	1″	1/4″
15/64″	3-7/8″	2-5/8″	29#	2-7/8″	1-3/4″	75#	1″	1/4″
1/4″	4″	2-3/4″	30#	2-3/4″	1-5/8″	76#	7/8″	3/16″
17/64″	4-1/8″	2-7/8″	31#	2-3/4″	1-5/8″	77#	7/8″	3/16″
9/32″	4-1/4″	2-15/16″	32#	2-3/4″	1-5/8″	78#	7/8″	3/16″
19/64″	4-3/8″	3-1/16″	33#	2-5/8″	1-1/2″	79#	3/4″	1/8″
5/16″	4-1/2″	3-3/16″	34#	2-5/8″	1-1/2″	80#	3/4″	1/8″
21/64″	4-5/8″	3-5/16″	35#	2-5/8″	1-1/2″	A	3-/7/8″	2-5/8″
11/32″	4-3/4″	3-7/16″	36#	2-1/2″	1-7/16″	B	4″	2-3/4″
23/64″	4-7/8″	3-1/2″	37#	2-1/2″	1-7/16″	C	4″	2-3/4″
3/8″	5″	3-5/8″	38#	2-1/2″	1-7/16″	D	4″	2-3/4″
25/64″	5-1/8″	3-3/4″	39#	2-3/8″	1-3/8”	E	4″	2-3/4″
13/32″	5-1/4″	3-7/8″	40#	2-3/8″	1-3/8″	F	4-/1/8″	2-7/8″
27/64″	5-3/8″	3-15/16″	41#	2-3/8″	1-3/8″	G	4-/1/8″	2-7/8″
7/16″	5-1/2″	4-1/16″	42#	2-1/4″	1-1/4″	H	4-/1/8″	2-7/8″
29/64″	5-5/8″	4-3/16″	43#	2-1/4″	1-1/4″	I	4-1/8”	2-7/8″
15/32″	5-3/4″	4-5/16″	44#	2-1/8″	1-1/8″	J	4-/1/8″	2-7/8″
31/64″	5-7/8″	4-3/8″	45#	2-1/8″	1-1/8″	K	4-/1/4″	2-15/16″
1/2″	6″	4-1/2″	46#	2-1/8″	1-1/8″	L	4-/1/4″	2-15/16″
1#	3-7/8″	2-5/8″	47#	2″	1″	M	4-3/8″	3-1/16″
2#	3-7/8″	2-5/8″	48#	2″	1″	N	4-3/8″	3-1/16″
3#	3-3/4″	2-1/2″	49#	2″	1″	O	4-1/2″	3-3/16″
4#	3-3/4″	2-1/2″	50#	2″	1″	P	4-5/8″	3-5/16″
5#	3-3/4″	2-1/2″	51#	2″	1″	Q	4-3/4″	3-7/16″
6#	3-3/4″	2-1/2″	52#	1-7/8″	7/8″	R	4-3/4″	3-7/16″
7#	3-5/8″	2-7/16″	53#	1-7/8″	7/8″	S	4-7/8″	3-1/2″
8#	3-5/8″	2-7/16″	54#	1-7/8″	7/8″	T	4-7/8″	3-1/2″
9#	3-5/8″	2-7/16″	55#	1-7/8″	7/8″	U	5″	3-5/8″
10#	3-5/8″	2-7/16″	56#	1-3/4″	3/4″	V	5″	3-5/8″
11#	3-1/2″	2-5/16″	57#	1-3/4″	3/4″	W	5-1/8″	3-3/4″
12#	3-1/2″	2-5/16″	58#	1-5/8″	11/16″	X	5-1/8″	3-3/4″
13#	3-1/2″	2-5/16″	59#	1-5/8″	11/16″	Y	5-1/4″	3-7/8″
14#	3-3/8″	2-3/16″	60#	1-5/8″	11/16″	Z	5-1/4″	37810″