42CrMo Hydraulic Cylinder Piston Hollow Rods Hard Chrome Plated
Steel Bar NSS 500 Hours
NSS Testing Standing une-en iso9227:2017
· Sal solution: 50 (+/- 5) g/l of NaCl. Water is demineralized and
salt purity is 99.5%.
· Environmental temperature: 35 °C.
· pH of salt solution is 6.8.
· Volumen of salt solution is 38.4 ml/day.
· Density of salt solution is 1,030 g/cm3.
· Spraying is 1.5 (+/- 0.5) ml/h.
Test Result :NSS can endure 300 hours ;500 hours; 800 hours
SGS NSS Testing Report TUV NSSTesting Repopt
Heat treatment
1.Quenching with fire about 860 °C, placed in furnace box
2. After quenching, put into the oil tank to cool from the box
furnace
3. After cooling, the first time tempering: tempered at 640 °C and
the hardness is controlled at about HRC28-32, the first time
tempering cooling is used Water-cooled.
4. Straightening: The outer circle is controlled by 200 um(0.2mm) ;
straightening equipment:
three-roller straightening machine；
hydraulic straightening machine (multipoint straightening)
5. The second tempering removes the hard force, the temperature is
about 480 °C, and Keep warm for 2 -2.5hours ; release 80% more or
less
CHEMICAL COMPOSITION
| Material | C% | Mn% | Si% | S% | P% | V% | Cr% |
| Ck45 | 0.42-0.50 | 0.50-0.80 | 0.04 | 0.035 | 0.035 | | |
| ST52 | 0.22 | 1.6 | 0.55 | 0.035 | 0.04 | | |
| 20MnV6 | 0.16-0.22 | 1.30-1.70 | 0.10-0.50 | 0.035 | 0.035 | 0.10-0.20 | |
| 42CrMo4 | 0.38-0.45 | 0.60-0.90 | 0.15-0.40 | 0.03 | 0.03 | | 0.90-1.20 |
| 40Cr | 0.37-0.45 | 0.50-0.80 | 0.17-0.37 | | | | 0.80-1.10 |
MECHANCIAL PROPERTIES |
| Material | T.S N/MM2 | Y.S N/MM2 | E%(MIN) | CHARPY | CONDITION | | CK45 | 610 | 355 | 15 | >41J | NORMALIZE | | CK45 | 800 | 630 | 20 | >41J | Q + T | | ST52 | 500 | 355 | 22 | | NORMALIZE | | 20MnV6 | 750 | 590 | 12 | >40J | NORMALIZE | | 42CrMo4 | 980 | 850 | 14 | >47J | Q + T | | 40Cr | 1000 | 800 | 10 | | Q + T |
|
Company Profile :
Dallast Technology Co., Ltd is a leading professional manufacturer of hydraulic cylinder more
than 15 years, we are specializing in developing, designing,
manufacturing, sales and after sales service of hydraulic cylinder,
not only the standard but also OEM products. In order to provide
better products to our customers, we make a huge investment to
introduce our advanced hydraulic technology at home and abroad,
such as CNC machine, automatic cylinder welding equipment, cylinder
turning center, plasma cutting machine etc.
