API 5CT is a specification for casing and tubing for petroleum and natural gas industries-used for wells. This Standard specifies the technical delivery conditions for steel pipes (casing, tubing and pup joints), coupling stock, coupling material and accessory material and establishes requirements for three Product Specification Levels (PSL-1, PSL-2, PSL-3).
API Q125 is an API 5CT oil casing pipe grades and mostly used for general use in deep wells with varied end connections such as non-upset ends or an external upset end. Impact testing is required for each heat and/or lot. NDT inspection typically EMI and UT are required on this product. WLD steel is a leading API 5CT casing and tubing manufacturer and supplier, we provide a broad range of API 5CT Q125 oilfield casing pipe, API 5CT Q125 tubing but also casing coupling, perforated pipe, and more.
API 5CT Grade Q125 Casing Tubing Color Code
Name |
Casing |
Coupling |
Q125 |
A bright orange band |
Entire orange coupling |
API 5CT Q125 Chemical Composition
Grades |
C |
Mn |
Mo |
Cr |
Ni |
P |
S |
Q125 Type1 |
≤0.35 |
≤1.00 |
≤0.75 |
≤1.20 |
≤0.99 |
0.02 |
0.01 |
Q125 Type2 |
≤0.35 |
≤1.00 |
NL |
NL |
≤0.99 |
0.020 |
0.020 |
Q125 Type3 |
≤0.50 |
≤1.90 |
NL |
NL |
≤0.99 |
0.030 |
0.020 |
Q125 Type4 |
≤0.50 |
≤1.90 |
NL |
NL |
≤0.99 |
0.030 |
0.020 |
API 5CT Q125 Mechanical Property
Grade |
Type |
Yield strength MPa |
Tensile strength min. MPa |
Total elongation under load % |
Q125 |
Type1-Type4 |
862-1034 |
≥931 |
0.65 |
API 5CT Q125 Tolerance
Item |
Allowable tolerance |
Outer diameter |
Pipe body |
D≤101.60mm±0.79mm |
D≥114.30mm+1.0% |
-0.5% |
Wall thickness |
-12.5% |
Wight |
Single piece |
+6.5%+3.5% |
Total weight |
-1.75 |
API 5CT Q125 Size Chart
Outer Diameter |
Wall Thickness |
Weight |
Grade |
Threaded |
Length |
in |
mm |
kg/m |
lb/ft |
4 1/2″ |
114.3 |
14.14-22.47 |
9.50-11.50 |
Q125 |
LTC/STC/BTC |
R1/R2/R3 |
5″ |
127 |
17.11-35.86 |
11.50-24.10 |
Q125 |
LTC/STC/BTC |
R1/R2/R3 |
5 1/2″ |
139.7 |
20.83-34.23 |
14.00-23.00 |
Q125 |
LTC/STC/BTC |
R1/R2/R3 |
6 5/8″ |
168.28 |
29.76-35.72 |
20.00-24.00 |
Q125 |
LTC/STC/BTC |
R1/R2/R3 |
7″ |
177.8 |
25.30-56.55 |
17.00-38.00 |
Q125 |
LTC/STC/BTC |
R1/R2/R3 |
7 5/8″ |
193.68 |
35.72-63.69 |
24.00-42.80 |
Q125 |
LTC/STC/BTC |
R1/R2/R3 |
8 5/8″ |
219.08 |
35.72-72.92 |
24.00-49.00 |
Q125 |
LTC/STC/BTC |
R1/R2/R3 |
9 5/8″ |
244.48 |
48.07-86.91 |
32.30-58.40 |
Q125 |
LTC/STC/BTC |
R1/R2/R3 |
10 3/4″ |
273.05 |
48.73-97.77 |
32.75-65.70 |
Q125 |
LTC/STC/BTC |
R1/R2/R3 |
11 3/4″ |
298.45 |
62.50-89.29 |
42.00-60.00 |
Q125 |
LTC/STC/BTC |
R1/R2/R3 |
13 3/8″ |
339.72 |
71.43-107.15 |
48.00-72.00 |
Q125 |
LTC/STC/BTC |
R1/R2/R3 |