17.8-80 Welding drill bitDetailed product description：

This drill bit uses an oil feeder to supply coolant and an internal chip removal process. It can drill deep holes in solid materials such as carbon steel and alloy steel, with a length to diameter ratio of up to 1:100.

Unit: mm

bit size	Equipped with a knife holder	bit size	Equipped with a knife holder
17.8-19.5	sixteen	43 45 47	forty
19.51-21.99	seventeen point five	48 50 52	forty-three
22-24.99	twenty	fifty-five	forty-eight
25-26.99	twenty-three	57 58 60	fifty-two
27-29.99	twenty-five	62 63 65	fifty-six
30-31.99	twenty-seven	68 70 72	sixty-one
34.5-35	thirty	seventy-five	sixty-five
38-42	thirty-five	eighty	seventy

17.8-80 Welding Drill Bit