Project Description

JIS G3445 STKM11A, STKM 12A, STKM13A are the standards

applicable to carbon steel tubes for machine structural purposes

Application

JIS G3445 STKM 11A, STKM 12A, STKM 13A, STKM 15A, STKM 17A carbon steel tubes used for machinery, automobiles, bicycles, furniture, appliances and other machine parts.

Grade and Designation
The grade and designation of the tube shall be as given as follows table.

The sub classification letter symbols A, B and C are used to indicate distinction of method of manufacturing the tube, cold working process, heat treatment, etc.

Quick Inquiry

GradeDesignation
Grade 11ASTKM 11A
Grade 12ASTKM 12A
BSTKM 12B
CSTKM 12C
Grade 13ASTKM 13A
BSTKM 13B
CSTKM 13C
Grade 14ASTKM 14A
BSTKM 14B
CSTKM 14C
Grade 15ASTKM 15A
CSTKM 15C
Grade 16ASTKM 16A
CSTKM 16C
Grade 17ASTKM 17A
CSTKM 17C
Grade 18ASTKM 18A
BSTKM 18B
CSTKM 18C
Grade 19ASTKM 19A
CSTKM 19C
Grade 20ASTKM 20A

Chemical Composition

GradeDesignationUnit %
CSiMnPSNb or V
Grade 11ASTKM 11A0.12 max.0.35 max.0.60 max.0.040 max.0.040 max.
Grade 12ASTKM 12A0.20 max.0.35 max.0.60 max.0.040 max.0.040 max.
BSTKM 12B
CSTKM 12C
Grade 13ASTKM 13A0.25 max.0.35 max.0.30~0.900.040 max.0.040 max.
BSTKM 13B
CSTKM 13C
Grade 14ASTKM 14A0.30 max.0.35 max.0.30~1.000.040 max.0.040 max.
BSTKM 14B
CSTKM 14C
Grade 15ASTKM 15A0.25~0.350.35 max.0.30~1.000.040 max.0.040 max.
CSTKM 15C
Grade 16ASTKM 16A0.35~0.450.40 max.0.40~1.000.040 max.0.040 max.
CSTKM 16C
Grade 17ASTKM 17A0.45~0.550.40 max.0.40~1.000.040 max.0.040 max.
CSTKM 17C
Grade 18ASTKM 18A0.18 max.0.55 max.1.50 max.0.040 max.0.040 max.
BSTKM 18B
CSTKM 18C
Grade 19ASTKM 19A0.25 max.0.55 max.1.50 max.0.040 max.0.040 max.
CSTKM 19C
Grade 20ASTKM 20A0.25 max.0.55 max.1.60 max.0.040 max.0.040 max.0.15 max.

Mechanical Properties

Design
-ation
Tensile
Strength
N/П
{kgf/П}
Yield
point
or
proof
N/П
{kgf/П}
Elongation %Flattening strength
Distance between flat plates (H)
(D is outside dia. of the tube)
Bending Strength
No.4No.4Bend AngleInside radius
No.11No.5(D is outside dia. of the tube)
No.12Test Pieces Transverse Direction
Test Pieces Longitudinal Direction
STKM11A290{30} min.35 min.30 min.1/2 D1804 D
STKM12A340{35} min.175{18} min.35 min.30 min.2/3 D906 D
STKM12B390{40} min.275{28} min.25 min.20 min.2/3 D906 D
STKM12C470{48} min.355{36} min.20 min.15 min.
STKM13A370{38} min.215{22} min.30 min.25 min.2/3 D906 D
STKM13B440{45} min.305{31} min.20 min.15 min.3/4 D906 D
STKM13C510{52} min.380{39} min.15 min.10 min.
STKM14A410{42} min.245{25} min.25 min.20 min.3/4 D906 D
STKM14B500{51} min.355{36} min.15 min.10 min.7/8 D908 D
STKM14C550{56} min.410{42} min.15 min.10 min.
STKM15A470{48} min.275{28} min.22 min.17 min.3/4 D906 D
STKM15C580{59} min.430{44} min.12 min.7 min.
STKM16A510{52} min.325{33} min.20 min.15 min.7/8 D908 D
STKM16C620{63} min.460{47} min.12 min.7 min.
STKM17A550{56} min.345{35} min.20 min.15 min.7/8 D908 D
STKM17C650{66} min.480{49} min.10 min.5 min.
STKM18A440{45} min.275{28} min.25 min.20 min.7/8 D906 D
STKM18B490{50} min.315{32} min.23 min.18 min.7/8 D908 D
STKM18C510{52} min.380{39} min.15 min.10 min.
STKM19A490{50} min.315{32} min.23 min.18 min.7/8 D906 D
STKM19C550{56} min.410{42} min.15 min.10 min.
STKM20A540{55} min.390{40} min.23 min.18 min.7/8 D906 D

Quick Inquiry

Appearance

  • The tubes shall be practically straight. and the two ends shall be at right angles to the axis of the tube
  • The tubes shall be free from defects detrimental to practical use.
  • The surface finish of the tubes, when especially specified shall be agreed upon by the purchaser and the manufacturer.

Tolerance on Outside Diameter

DivisionTolerances on outside diameter
No. 1  Under 50mm                 ±0.5mm
  50mm or over                ±1%
No. 2  Under 50mm                 ±0.25mm
  50mm or over                ±0.5%
No. 3  Under 25mm                 ±0.12mm
  25mm or over to and excl. 40mm   ±0.15mm
  40mm or over to and excl. 50mm   ±0.18mm
  50mm or over to and excl. 60mm   ±0.20mm
  60mm or over to and excl. 70mm   ±0.23mm
  70mm or over to and excl. 80mm   ±0.25mm
  80mm or over to and excl. 90mm   ±0.30mm
  90mm or over to and excl.100mm   ±0.40mm
  100mm or over               ±0.50%

Tolerance on Thickness

DivisionTolerances on wall thickness
No. 1Under 4mm
+0.6mm
 -0.5mm
4mm or over
15%
-12.50%
   N. 2Under 3mm
±0.3mm
3mm or over

Standard: JIS G3445

Description Name: STKM 11A Steel tube, STKM 12A steel tubes, STKM 13A steel tubes

Size: 4mm, 5mm, 6mm, 8mm, 10mm, 12mm, 14mm, 16mm, 18mm, 20mm.

W.T.: 0.6mm-8mm

Shape: Round

Production type: Cold drawn, cold rolled

Length: Single random length/ Double random length or as customer’s actual request max length is 10m

Grade: STKM 11A, STKM 12A, STKM 12C, STKM 12B, STKM 13A, STKM 13B, STKM 13C, STKM 15A, STKM 17A,

Click to download the details of JIS G3445 STKM11A Seamless Steel Tubes.

click to download pdf button

Note:

  • Mill test certificates will be issued according to EN10204.3
  • The tubes Shall be Seamless or Welded.

Protection and Packing:

  • Packed in wooden box or bundles protected with plastic paper, and suitably protected for sea-worthily delivery or as requested.
  • The tubes shall be delivered with a temporary corrosion protection. The type of protection shall be at the discretion of the manufacturer

Photos

STKM 11A Seamless Steel Tube OD Inspection

STKM 11A Seamless Steel Tube OD Inspection

STKM 11A Seamless Steel Tube Wall Thickness Inspection

STKM 11A Seamless Steel Tube Wall Thickness Inspection

STKM 11A Size 61mm Seamless Tubes

STKM 11A Size 61mm Seamless Tubes

Get in Touch

If you are interested in our products or service, please contact us now.

Tel.: +86 185 5109 0083 | E-mail: cts@ctstubes.com

Send Email

Standard and Product List