Special anti-corrosion metal coatingNPS、Ni-P alloy cladding（HAILIN system ）
Ni—P scope of cladding
1. Column tube, carbon-steel water cooler, air cooler ,re-boiler tube and other non-style heat exchanger.
2.Working temperature is within 700℃.
3.Protection of steel pipes, tubes, shell and impellers of mud pump, column pump and submersible pump.
Implementation standards
GB/T13913《rules and testing methods for metal layer by chemical Ni- P alloy paiting》
Ni—P suitable medium for cladding
1.Freshwater, salt water, ocean water, industrial cycling water, distilled water and vaor.
2.Chemical medium with acid-resistance, alkali-resistance , salt-resistance and sewage resistance.
3.All types of oil medium and benzene, hydrogen sulfide.
Ni—P technical index of cladding
1.ISO 2819 testing method and review on bonding strength of coating
2.Ni—P test and evaluate the coating of alloy coating according to international standard ISO 4527：
A.ISO 2819 testing method and review on bonding strength of coating
B.ISO 3768 neutral salt-spray test for coating（NNStest）
C.ISO 3700 copper accelerated salt-spray test for coating（CASS test）
D.ISO 4516 vickers hardness and knoop hardness test for coating
E.ISO 4527 thickness testing standard for coating
F.ISO 4527 porosity testing standard of coating
G.ISO 4527 phosphorus testing standard for coating
3.Ni—P physical performance of alloy coating:Chamfering the Column steel with 50μm, the coating no caving, no cracks, means good cohesion between coating and steel.( see list7, list 8)
Ni—P physical performance of alloy coatin
|
试验项目
|
结果
|
试验方法
|
|
硬度 HV50
|
镀态550 热处理后950
|
ISO 4527 6.4
|
|
内应力kgf/mm
|
-3.7-4.1
|
|
|
附着力 热震，300℃
|
1级
|
ISO 4527 6.5
|
|
Taber磨损试验指数 磨轮CS－17
失重mg/1000CyCles
|
镀态、14.524
热处理后3.34
|
ISO 4527 6.9
|
Not:Ni—P physical mechanical performance of coating
Ni—P testing results of coating hardness shows that the hardness of low Ni coating with 1~4Wt%P is around 700HV, the hardness can reach 1000HV after heat treatment, which is close to or even exceed the hard Cr. Coating, and it can substitute the hard Cr. Coating in some conditions.
Mechanical performance of Ni—P alloy coating
|
机械性能
|
1-4Wt%p
|
7-9Wt%p
|
10-12Wt%p
|
|
杨氏模数（GPa）
|
50-52
|
50-60 60-66（4-7Wt%p）
|
50-60
|
|
拉伸强度（Mpa）
|
150-200
|
800-1100
|
750-900
|
|
（钢铁上）内应力（KP/mm）
|
-+10
|
-±5
|
--5
|
|
延伸率
|
<0.5
|
-0.7
|
-1.5
|
|
镀后硬度（HRC）
|
650-700
|
550-600
|
500-550
|
|
400℃热处理1小时（HRC）
|
-1000
|
-1030
|
-1050
|
Corrosion rate of Chemical Ni—P(10%) alloy coating in all kinds of medium
|
介质分类
|
介质名称
|
介质温度℃
|
腐蚀率mm/Y
|
|
Ni-p
|
Cr18Ni9不锈钢
|
|
水
|
海水
|
30
|
0.0385
|
>1.5
|
|
|
|
50
|
0.253
|
>1.5
|
|
酸溶液
|
30%HCl
|
30
|
0.407
|
>1.5
|
|
|
|
50
|
1.001
|
>1.5
|
|
|
10%H2SO4
|
30
|
0.0424
|
>1.5
|
|
|
|
60
|
0.185
|
>1.5
|
|
|
38%H3PO4
|
60
|
0.0632
|
>1.5
|
|
|
16%HNO3
|
30
|
72.45
|
<0.05
|
|
|
35%草酸
|
沸腾
|
0.0363
|
>1.5G
|
|
|
28%醋酸
|
沸腾
|
0.0779
|
>1.5
|
|
|
50%柠檬酸
|
60
|
0.0350
|
0.05-0.5G
|
|
|
40%氢氟酸
|
30
|
0.0141
|
<1.5G.S
|
|
碱溶液
|
20%NaOH
|
沸腾
|
<0.048
|
>1.5
|
|
盐溶液
|
30%次氯酸钠
|
50
|
<0.001
|
>1.5P.G
|
|
|
20%过氯酸钠
|
沸腾
|
<0.001
|
0.05-0.5
|
|
|
20%重铬酸钾
|
沸腾
|
<0.001
|
0.5-1.5
|
|
|
20%氯化铵
|
沸腾
|
0.0874
|
0.5-1.5
|
Not:From this comparison, carbon-steel coatingNi—P spends lower cost than stainless steel , meanwhile the function of anti-corrosion and anti-abrasion is superior to 316 stainless steel ,glasses and fluorine plastics. Therefore it’s reasonable from all respects including anti-corrosion and useful life.
|
