A completely new elevator to replace the old one
WHEN TO REPLACE AN ELEVATOR?
We recommend full replacement if your elevator has a small, cramped car, takes a long time to travel between floors, is often out of order and is 15 years old or more.
With CEP full elevator replacement you will improve user safety and comfort, increase building values and reduce unplanned repair costs. All this is possible hassle-free thanks to our installation process.
FULL REPLACEMENT SOLUTIONS
We offer 30 eco-efficient full elevator replacement solutions. Find out more below.
Full Elevator Replacement,Mrl Commercial Elevators,Hospital Bed Elevators,Residential Elevators CEP Elevator Products ( China ) Co., Ltd. , https://www.zjelevatorcontrolsystem.com
/*728*90 created on 2018/5/16*/ var cpro_id = "u3440131"; Home>Bearing knowledge>New plating process for sliding bearing antifriction layer (1) New plating process for anti-friction layer of sliding bearing (1)
(China Shipbuilding Industry Corporation Chongqing Yuejin Machinery Factory Wu Wenjun) /*250*250 was created on 2017/12/25*/ var cpro_id = 'u3171089';
[Abstract] The orthogonal experimental method was used to investigate the influence of the content of the relevant components in the electroplating solution of the sliding bearing (also known as the bearing bush) and the process parameters on the coating function. The electroplating process was further optimized; the plating quality was significantly improved. Satisfied with the demand for the quality of sliding bearings in the new model of the main engine factory.
1 Preface <br> Sliding bearings (also known as bearing bushes) used in internal combustion engines are vulnerable parts. After machining, the nickel (Ni) grid of 1~3μm thickness is usually firstly plated on the inner and outer substrates. Barrier layer [1~2]; followed by electroplating 15~30μm thick lead-tin-copper (PbSnCu) ternary alloy anti-friction layer [3~24]; end of plating 1~2μm thick tin (Sn) on all surfaces or Lead-tin (PbSn) alloy protective layer [2].
The purpose of supplying the anti-friction layer on the inner and outer surfaces of the bearing bush is to improve the friction reducing, wear resistance, corrosion resistance, inlaying, compliance, running-in, seizure resistance, fatigue strength, compressive strength and load bearing of the bearing bush. Can wait; then improve its job function; extend the life of the application; end to ensure the high-function operation of the host.
Usually, the coating type is selected according to the application requirements. The bearing bush of small engine usually uses PbSn6~20 binary alloy [12~13, 16~17, 22]; also uses lead copper (PbCu), lead silver (PbAg) binary alloy. With the passage of time and the development of science and technology; about the bearing bush used in large and medium-sized diesel engines and internal combustion engines; the demand has large load and long service life; and it should have outstanding lubricity, corrosion resistance and wear resistance. It has been proved that the participation of a small amount of the third component element copper (Cu) in the conventional lead-tin (PbSn6~20) binary alloy anti-wear coating can significantly improve the coating function [3, 10, 20]. PbSn6~20) Binary alloy plating participates in 2~3% copper; on the one hand, copper and tin have a certain affinity; in a certain degree, the tin is dispersed to the fabric (ie, the matrix); The stability of the tin content and the metallographic layout, on the other hand; because of the participation in the copper; the hardness of the coating improved from the original HV8~10 to HV13~15; greatly improved the wear resistance and fatigue strength of the coating; Then significantly improved the load capacity of the bearing bush; the service life is greatly Degree extension.
If the anti-friction coating is directly electroplated on the fabric metal; the tin in the coating is simply dispersed to the fabric; after the bearing is in operation for a while; the tin content in the coating is reduced to less than 6% (mass). And whether it is a copper-based alloy fabric It is still an aluminum-based alloy fabric; it is rich in a certain amount of copper; the tin dispersed in the fabric can form a brittle intermetallic compound (Cu3Sn) with copper. This not only reduces the mechanical function of the coating, but also destroys the fabric. Layout; to reduce the overall mechanical function of the bearing. The method of dealing with this problem is to plate a layer of nickel or nickel-based alloy barrier (also known as gate layer or barrier layer) between the fabric material and the anti-friction bottom layer; Fabric dispersion [1~2].
The tin or lead-tin alloy protective layer not only has a certain anti-corrosion effect; it can also disperse the amount of tin in the anti-friction layer in the working time of the bearing bush; the content of each component is relatively stable. Because this layer of protective layer contains no copper; it is relatively soft; therefore, the bearing bush can reach the outstanding running-in demand at the beginning of the operation.
This paper first investigates the electroplating process of the bearing friction layer.
2 Carrying out the process <br> The research on anti-friction coatings started earlier. In 1920, J. Grooff proposed the first patent of electroplated lead-tin alloy; and it was used for the internal and external appearance of the sailor torpedo gas cylinder. Electroplating; to the beginning of the 1940s for the plating of bearing pads. In 1952 Schults proposed a patent for electroplating lead-tin-copper ternary alloys on aluminum and aluminum-silicon (AlSi) alloy substrates. Schoefe has announced the use of lead-tin-copper alloys in bushings. In 1976; Jong Sang Kim; Su ιι Pyun and Hyo Geun Lee announced the paper "Pore-Orientation and Microscopic Tracing of Lead-Silver Copper Electroplating Layers" [7] ]. In 1980, Beebe proposed copper-containing 2~3% (mass) and tin 9~12% (mass); other copper-based ternary alloy electroplating production process; coating thickness is 15μm. 1982 Water Waterman et al. proposed a treatment method for the replacement of copper ions (Cu2+) in ternary alloy plating bath.
The domestic research and use of anti-friction alloy coating started late. In 1960, the first research and development and application of brush-plated tin-tin alloy technology by Wuhan Data Insurance Research Institute and Hailing Top Parts Factory has been used for electroplating of speedboat engines. In the mid-1970s; Shanghai Alloy Bearing Factory and Shanghai East Shipyard made a detailed discussion on the electroplating of copper and tin alloys [12~13].1985; Harbin Institute of Technology Electrochemical Teaching and Research Institute and China National Shipbuilding Corporation The 466-600 factory jointly studied the process of electroplating lead-tin-copper ternary alloy anti-friction layer on lead bronze sliding bearing; it has been used in production. In 1989, Dusanka Radoric announced "hydroquinone in fluoroborate plating solution". (Pb-tin phenol) is an additive for lead-tin alloy plating. 16. The end of the tenth century; Fan Jiahua and Jiang Zhidong 21, 24 of Nantong Bearing Factory; Zeng Liangyu, Yang Xiangui, Wang Huiwen 8, 17 of Wuhan Data Insurance Research Institute; Qin Shengyi 9 of Guangxi Guilin Internal Combustion Engine Parts Factory; Xue Shusheng 20 of Qishuyan Locomotive and Rolling Stock Technology Research Institute has carried out different degrees of electroplating process on the anti-friction layer. Discussed; certainly laid the foundation for the further improvement of the production process in use.
3 The problem of the problem <br> The electroplating process of the anti-friction coating of the lead-tin-copper ternary alloy of our factory is the first in China; for many years, it has supplied a lot of bearing bushes for the mainframe parts shopping malls in China. These years; the order quantity of the bearing products of our factory has increased year by year; Moreover, some bearing products have entered the world market. Yu Xinghuan Kangmou. This fully reflects the strong strength of our factory's bearing products in the fierce shopping mall competition.
From 1989 to 1991; after our hard work and repeated experiments; it has fundamentally dealt with the problem of the fatality of the adhesion of the bearing layer, such as foaming and peeling, which eliminates the problem of the substrate being subjected to batch serious corrosion and overcomes The batch wall thickness is out of tolerance; the process capability is improved, and the waste loss rate has always been very low; the rate of qualified products for one inspection has improved year by year.
However, defects such as rough coating, nodule, spot, pit, and airflow stripe sometimes occur; sometimes the cathode current density (DK) does not reach the scale of the process.
The above-mentioned shortcomings of the anti-friction coating directly affect the quality of the bearing products. With the continuous upgrading of the main engine model, the localization of imported models and the increasingly fierce competition in the shopping malls; the demand for the quality of the bearing products is getting higher and higher. Fundamentally speaking, it is the competition of product quality. Under the situation that users are increasingly demanding the quality indicators of products; we are faced with a serious challenge to improve the plating process of the bearing bush and further improve the quality of the bearing products.
Recommend to friends comments close window Bearing related knowledge Talking about the selection method of bearing equipment how to buy agricultural machinery bearings
Functional review of NSK bearings
Analysis of the use of tapping skills in SKF bearings
This article links to http://
Please indicate the bearing network http://
Previous:Massage gearbox bearing application technology (1)
Next: The use of low-oscillation bearings - Oscillation caused by error/shape accuracy and its countermeasures
Source: China Bearing Network Time: 2013-06-21