Mae pibellau dur JIS 3445 yn addas ar gyfer peiriannau, automobiles, beiciau, dodrefn, offer a rhannau mecanyddol eraill. Y prif raddau yw STKM11A, STKM12(A,B,C), STKM12(A,B,C), STKM(A,B,C).
Mae Cyfansoddiad Cemegol Tiwbiau Mecanyddol JIS 3445 STKM11, STKM12, STKM13 a STKM14 fel y tabl isod:
| Gradd | Cyfansoddiad Cemegol % | |||||
| C | Os | Mn | P | S | Nb neu V | |
| STKM11A | Llai na neu'n hafal i 0.12 | Llai na neu'n hafal i 0.35 | Llai na neu'n hafal i 0.60 | Llai na neu'n hafal i 0.040 | Llai na neu'n hafal i 0.040 | ▾ |
| STKM12A | Llai na neu'n hafal i 0.20 | Llai na neu'n hafal i 0.35 | Llai na neu'n hafal i 0.60 | Llai na neu'n hafal i 0.040 | Llai na neu'n hafal i 0.040 | - |
| STKM12B | ||||||
| STKM12C | ||||||
| STKM13A | Llai na neu'n hafal i 0.25 | Llai na neu'n hafal i 0.35 | 0.30~ 0.90 |
Llai na neu'n hafal i 0.040 | Llai na neu'n hafal i 0.040 | - |
| STKM13B | ||||||
| STKM13C | ||||||
| STKM14A | Llai na neu'n hafal i 0.30 | Llai na neu'n hafal i 0.35 | 0.30~ 1.00 |
Llai na neu'n hafal i 0.040 | Llai na neu'n hafal i 0.040 | - |
| STKM14B | ||||||
| STKM14C | ||||||
Mae Priodweddau Mecanyddol JIS 3445 STKM11, STKM12, STKM13 a STKM14 Tiwbiau Mecanyddol Dur Carbon fel y tabl isod:
| Gradd | Priodweddau Mecanyddol | Prawf gwastadu | Prawf Plygu | |||
| Cryfder Tynnol (MPa) |
Cryfder Cynnyrch (MPa) |
elongation (%) | Pellter rhwng y rhannau hynny (D=OD) |
Plygwch Ongl |
Y tu mewn Radiws (D=OD) |
|
| Rhif 11: Sbesimen | ||||||
| STKM11A | 230 (294) |
- | 235 | 1/2D | 180 gradd | 4D |
| STKM12A | 235 (343) |
218 (177) |
235 | 2/3D | 90 gradd | 6D |
| STKM12B | 240 (392) |
228 (275) |
225 | 2/3D | 90 gradd | 6D |
| STKM12C | 248 (471) |
236 (353) |
220 | - | - | - |
| STKM13A% 3b | 238 (373) |
222 (216) |
230 | 2/3D | 90 gradd | 6D |
| STKM13B | 245 (441) |
231 (304) |
220 | 3/4D | 90 gradd | 6D |
| STKM13C | 252 (510) |
239 (382) |
215 | - | - | - |
| STKM14A | 242 (412) |
225 (245) |
225 | 3/4D | 90 gradd | 6D |
| STKM14B | 251 (500) |
236 (353) |
215 | 7/8D | 90 gradd | 8D |
| STKM14C | 256 (549) |
242 (412) |
215 | - | - | - |
Goddefiannau Tiwb JIS G3445 STKM12A/STKM12B ar y Diamedr Allanol:
Rhif 1: pan diamedr allanol<50mm, tolerance 0.5mm;when outer diameter ≥50 mm,tolerance +/- 0.1mm;
Rhif 2: pan diamedr allanol<50mm, tolerance 0.25mm;when outer diameter ≥50 mm,tolerance +/- 0.5mm;
Rhif 3: pan diamedr allanol<25mm, tolerance 0.12mm;when 25mm ≤od ≥40 mm,tolerance +/- 0.15mm;
pan fydd 40mm Llai na neu'n hafal i od Mwy na neu'n hafal i 50 mm,goddefiant +/- 0.18mm.
