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Kelly
Product Introduction
Kelly is the drive part of whole drill string, it transmits the torsional energy from the rotary table to the bit in the bottom of the hole. Kelly is supported by the swivel through the rotary table and connected to the first joint of drill pipe in the drill string. Kelly has been approved by the API certification. Straightness is the key manufacturing process. Straightness is checked before, during and after each machining operation. Flats are precision-milled to API specifications. All millings are performed on specially designed rigid Kelly mills. Each Kelly is furnished with a pressed steel thread protector. We supply both square kelly and hexagonal kelly.
Product Details

• Kelly is manufactured strictly according to API Spec7-1 standard. Manufactured from AISI 4145H-modified, fully heat-treated alloy steel with aBrinell hardness range of 285-341 and a minimum average Charpy impact value of 40 ft-lbs.

• The end, drive section and connection of Kelly are machined and inspected according to API  standard.

• Ends and drive sections, IDs and connections machined and inspected to API specifications.

• Kelly bars are ultrasonically inspected over full length and section.

• Shipped in a protective steel-cased scabbard.

Specifications
Item Name Standard Size Upper box connection(LH) Lower pin connection Drive Overall length
Connection O.D in Bevel diameter mm Upset length Connection OD. in ID. Bevel diameter mm Upset length Section length
in
±0.8 ±0.4 in

±0.8 in ±0.4 in ft ft
1 Square Kelly Standard 2.1/2 6.5/8"REG 7.3/4 186.1 16 NC26 2.3/8"IF 3.3/8 1.1/4 83 20 37 40
2 Square Kelly Optional 2.1/2 4.1/2"REG 5.3/4 134.5 16 NC26 2.3/8"IF 3.3/8 1.1/4 83 20 37 40
3 Square Kelly Standard 3 6.5/8"REG 7.3/4 186.1 16 NC31 2.7/8"IF 4.1/8 1.3/4 100.4 20 37 40
4 Square Kelly Optional 3 4.1/2"REG 5.3/4 134.5 16 NC31 2.7/8"IF 4.1/8 1.3/4 100.4 20 37 40
5 Square Kelly Standard 3.1/2 6.5/8"REG 7.3/4 186.1 16 NC38 3.1/2"IF 4.3/4 2.1/4 116.3 20 37 40
6 Square Kelly Optional 3.1/2 4.1/2"REG 5.3/4 134.5 16 NC38 3.1/2"IF 4.3/4 2.1/4 116.3 20 37 40
7 Square Kelly Standard 4.1/4 6.5/8"REG 7.3/4 186.1 16 NC46 4"IF 6.1/4 2.13/16 145.2 20 37 40
8 Square Kelly Standard 4.1/4 6.5/8"REG 7.3/4 186.1 16 NC50 4.1/2"IF 6.3/8 2.13/16 154 20 37 40
9 Square Kelly Optional 4.1/4 4.1/2"REG 5.3/4 134.5 16 NC46 4"IF 6.1/4 2.13/16 145.2 20 37 40
10 Square Kelly Optional 4.1/4 4.1/2"REG 5.3/4 134.5 16 NC50 4.1/2"IF 6.3/8 2.13/16 154 20 37 40
11 Square Kelly Standard 4.1/4 6.5/8"REG 7.3/4 186.1 16 NC46 4"IF 6.1/4 2.13/16 145.2 20 51 54
12 Square Kelly Standard 4.1/4 6.5/8"REG 7.3/4 186.1 16 NC50 4.1/2"IF 6.3/8 2.13/16 154 20 51 54
13 Square Kelly Optional 4.1/4 4.1/2"REG 5.3/4 134.5 16 NC46 4"IF 6.1/4 2.13/16 145.2 20 51 54
14 Square Kelly Optional 4.1/4 4.1/2"REG 5.3/4 134.5 16 NC50 4.1/2"IF 6.3/8 2.13/16 154 20 51 54
15 Square Kelly Standard 5.1/4 6.5/8"REG 7.3/4 186.1 16 5.1/2"FH 7 3.1/4 170.6 20 37 40
16 Square Kelly Standard 5.1/4 6.5/8"REG 7.3/4 186.1 16 NC56 7 3.1/4 171 20 37 40
17 Square Kelly Standard 5.1/4 6.5/8"REG 7.3/4 186.1 16 5.1/2"FH 7 3.1/4 170.6 20 51 54
18 Square Kelly Standard 5.1/4 6.5/8"REG 7.3/4 186.1 16 NC56 7 3.1/4 171 20 51 54
19 Hex Kelly Standard 3 6.5/8"REG 7.3/4 186.1 16 NC26 2.3/8"IF 3.3/8 1.1/4 82.9 20 37 40
20 Hex Kelly Optional 3 4.1/2"REG 5.3/4 134.5 16 NC26 2.3/8"IF 3.3/8 1.1/4 82.9 20 37 40
21 Hex Kelly Standard 3.1/2 6.5/8"REG 7.3/4 186.1 16 NC31 2.7/8"IF 4.1/8 1.3/4 100.4 20 37 40
22 Hex Kelly Optional 3.1/2 4.1/2"REG 5.3/4 134.5 16 NC31 2.7/8"IF 4.1/8 1.3/4 100.4 20 37 40
23 Hex Kelly Standard 4.1/4 6.5/8"REG 7.3/4 186.1 16 NC38 3.1/2"IF 4.3/4 2.1/4 116.3 20 37 40
24 Hex Kelly Optional 4.1/4 4.1/2"REG 5.3/4 134.5 16 NC38 3.1/2"IF 4.3/4 2.1/4 116.3 20 37 40
25 Hex Kelly Optional 4.1/4 6.5/8"REG 7.3/4 186.1 16 NC38 3.1/2"IF 4.3/4 2.1/4 116.3 20 51 54
26 Hex Kelly Optional 4.1/4 4.1/2"REG 5.3/4 134.5 16 NC38 3.1/2"IF 4.3/4 2.1/4 116.3 20 51 54
27 Hex Kelly Standard 5.1/4 6.5/8"REG 7.3/4 186.1 16 NC46 4"IF 6.1/4 3 145.2 20 37 40
28 Hex Kelly Standard 5.1/4 6.5/8"REG 7.3/4 186.1 16 NC50 4.1/2"IF 6.3/8 3.1/4 154 20 37 40
29 Hex Kelly Optional 5.1/4 6.5/8"REG 7.3/4 186.1 16 NC46 4"IF 6.1/4 3 145.2 20 51 54
30 Hex Kelly Optional 5.1/4 6.5/8"REG 7.3/4 186.1 16 NC50 4.1/2"IF 6.3/8 3.1/4 154 20 51 54
31 Hex Kelly Standard 6 6.5/8"REG 7.3/4 186.1 16 5.1/2"FH 7 3.1/2 170.6 20 37 40
32 Hex Kelly Standard 6 6.5/8"REG 7.3/4 186.1 16 NC56 7 3.1/2 171 20 37 40
33 Hex Kelly Standard 6 6.5/8"REG 7.3/4 186.1 16 5.1/2"FH 7 3.1/2 170.6 20 51 54
34 Hex Kelly Standard 6 6.5/8"REG 7.3/4 186.1 16 NC56 7 3.1/2 171 20 51 54