API 11B

HOME > related posts

API 11B provides the requirements and guidelines for the design of steel sucker rods and pony rods, polished rods, polished rod liners, couplings and sub-couplings, fiber reinforced plastic (FRP) sucker rods, sinker bars, polished rod clamps, stuffing boxes, and pumping tees as defined herein for use in the sucker rod lift method for the petroleum and natural gas industry. Annex A through Annex H provide the requirements for specific products. Annex I includes the requirements for thread gauges, Annex J illustrates the components of a sucker rod lift system, and Annex K shows examples of sucker rod discontinuities.

However, API 11B does not cover sucker rod guides, sucker rod rotators, shear tools, on-off tools, stabilizer bars, sealing elements used in stuffing boxes, or interface connections for stuffing boxes and pumping tees. Also, installation, operation and maintenance of these products are not included in this specification.

API 11B Steel Sucker Rods

Grade C sucker rod is made from fine carbon steel. It is featured by mid-strength, good plasticity, toughness, corrosion resistance. It is suitable for sour medium environment where it is no susceptible to sulphur stress cracking.

Grade D sucker rod is made from fine alloy steel, featured by high strength, better plasticity and long service life after heat treatment. This product is suitable for no-corrosion or light-corrosion environment oil-well widely.

Grade HL and HY sucker rod are super-high strength sucker rod, having the same size and main parameter as grade D sucker rod, but their strength is capable to reach 966-1195Mpa. Grade HL and HY sucker rod are suitable for the deep oil-well or big-pump capacity oil-well.

Grade K, KD and KH sucker rod are made from fine Cr-Ni-Mo alloy steel containing different amount of Ni. They possess more powerful anti-corrosion function. The products are suitable for strong corrosion oil-well, with depth of shallow, middle and deep respectively.

Chemical Composition(%):

Grade	C	Mn	Si	P	S	Cr	Ni	Mo	Cu	V
Grade C(25CrMnVA)(AISI 1526)	0.21-0.30	1.30-1.70	0.17-0.37	0.025 max	0.025 max	0.30 max	0.35 max	0.06 max	0.20 max	0.07 max
Grade K (20Ni2MoA)(AISI 4621)	0.18-0.23	0.70-0.90	0.17-0.37	0.025 max	0.025 max	0.35 max	1.65-2.00	0.20-0.30	0.20 max	0.07 max
Grade D (20CrMoA)(AISI 4119)	0.17-0.24	0.40-0.70	0.17-0.37	0.025 max	0.025 max	0.80-1.20	0.30 max	0.15-0.25	0.20 max	0.07 max
Grade KD (25NiMnCrMoA)(AISI 3130)	0.22-0.29	0.70-1.00	0.15-0.35	0.025 max	0.025 max	0.42-0.65	0.72-1.00	0.01-0.06	0.20 max	0.07 max
Grade HL (30CrMoA)(AISI 4130)	0.26-0.33	0.40-0.70	0.17-0.37	0.025 max	0.025 max	0.80-1.10	0.30 max	0.15-0.25	0.20 max	0.07 max
Grade HY (30CrMoA)(AISI 4130)	0.26-0.33	0.40-0.70	0.17-0.37	0.025 max	0.025 max	0.80-1.10	0.30 max	0.15-0.25	0.20 max	0.07 max
Grade KH (30CrNi2MoA)(AISI 4330)	0.28-0.35	0.70-0.90	0.17-0.37	0.025 max	0.025 max	0.80-1.10	1.65-2.00	0.20-0.30	0.20 max	0.07 max

Mechanical Properities:

Grade	Tensile Strength Rm (Mpa)	Yield Strength Rp0.2 (Mpa)	Elongation A(%)	Area Reduction Z(%)	Hardness (HRC)
C	621-793	414 min	12 min	55 min	16-23
K	621-793	414 min	12 min	55 min	16-23
D	793-965	586 min	10 min	50 min	23-32
KD	793-965	586 min	10 min	50 min	23-32
HL	965-1195	795 min	10 min	50 min	32-36
HY	965-1195	795 min	/	/	42 min
KH	965-1195	620 min	10 min	50 min	32-36

Dimensions and Tolerances for steel sucker rod:

Size (inch)

Diameter of Rod Body (mm)

Nominal Diameter of Thread (inch)

Outside Diameter of Pin Shoulder (mm)

Width of Wrench Square (mm)

Length of Wrench Square (mm)

Diameter of Bead (mm)

A (+/3.175)(mm)

C (+1.59, -0.40)(mm)

Diameter of Stress Relief (mm)

Length of Stress Relief (mm)

Length of Pin (mm)

Length of Sucker Rod (mm)

5/8

15.88 (+0.18, -0.36)

15/16

31.75 (+0.13, -0.25)

22.2(+/-0.79)

31.75 min

30.96 (+0.13, -3.18)

47.63

3.18

20.07

13.11

31.75

9042/7518

3/4

19.05 (+0.20, -0.41)

1 1/16

38.10 (+0.13, -0.25)

25.4 (+/-0.79)

31.75 min

35.72 (+0.13, -3.18)

57.15

3.18

23.24

15.09

36.51

9042/7518

7/8

22.23 (+0.20, -0.41)

1 3/16

41.28(+0.13, -0.25)

25.4 (+/-0.79)

31.75 min

38.10 (+0.13, -3.18)

66.68

4.76

26.42

17.07

41.28

9042/7518

25.4 (+0.23, -0.46)

1 3/8

50.80 (+0.13, -0.25)

33.3 (+/-0.79)

38.10 min

48.42 (+0.13, -4.76)

76.20

4.76

31.17

20.24

47.63

9042/7518

1 1/8

28.58 (+0.23, -0.51)

1 9/16

57.15 (+0.38, -0.38)

38.10 (+/-0.79)

41.28 min

55.56 (+0.13, -4.76)

85.73

4.76

35.92

22.23

53.98

9042/7518

Get In Touch