Each kelly shall be conduct 4145H full length heat treatment to ensure that hardness can reach 285-341HB at 1inch from OD; impact energy more than 54J...
Each kelly shall be conduct 4145H full length heat treatment to ensure that hardness can reach 285-341HB at 1inch from OD; impact energy more than 54J...
Each kelly shall be conduct 4145H full length heat treatment to ensure that hardness can reach 285-341HB at 1inch from OD; impact energy more than 54J...
Each kelly shall be conduct 4145H full length heat treatment to ensure that hardness can reach 285-341HB at 1inch from OD; impact energy more than 54J...
Each kelly shall be conduct 4145H full length heat treatment to ensure that hardness can reach 285-341HB at 1inch from OD; impact energy more than 54J...
Each kelly shall be conduct 4145H full length heat treatment to ensure that hardness can reach 285-341HB at 1inch from OD; impact energy more than 54J...
Each kelly shall be conduct 4145H full length heat treatment to ensure that hardness can reach 285-341HB at 1inch from OD; impact energy more than 54J...
Each kelly shall be conduct 4145H full length heat treatment to ensure that hardness can reach 285-341HB at 1inch from OD; impact energy more than 54J...
Each kelly shall be conduct 4145H full length heat treatment to ensure that hardness can reach 285-341HB at 1inch from OD; impact energy more than 54J...
Each kelly shall be conduct 4145H full length heat treatment to ensure that hardness can reach 285-341HB at 1inch from OD; impact energy more than 54J...