42CrMo Hydraulic Cylinder Piston Hollow Rods Hard Chrome Plated Steel Bar NSS 500 Hours
Material :42CrMo
Color :Black
NSS:Endure 300;500;800hours
Type:Hollow/Solid Rod
Application Environment:At sea or in harsh environments
Surface hardness:>HV860
SURFACE ROUGHNESS:Ra≤0.2 micron and Rt≤2 micro
TOLERANCES ON DIA:ISO f10 on the diameter
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
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
In the whole crafts process, there are 2 times remove hardening forces: the first remove hardening force in the heat treatment process, hardening force remove is about 80%; the second remove hardening force in the surface treatment process, hardening force remove is about 90%-95%. Therefore, the piston rod is not easily deformed during use or transportation.
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 | |||||||||||||||||||||||||||||||||||||||||||||||||
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