Maintenance of spring clutch

Common knowledge of spring clutch maintenance:
Most of the time the clutch spring is under the action of static pressure. If the clutch spring is used for a long time, plastic deformation will occur, the free length will be shortened and the elastic force will be weakened. When the elastic force of clutch spring is weakened, the torque transmitted by clutch will be reduced, and the power of engine can not be fully exerted, resulting in the powerlessness of locomotive.

Most of the time the clutch spring is under the action of static pressure. If the clutch spring is used for a long time, plastic deformation will occur, the free length will be shortened and the elastic force will be weakened. When the elastic force of clutch spring is weakened, the torque transmitted by clutch will be reduced, and the power of engine can not be fully exerted, resulting in the powerlessness of locomotive.

When it is found that the elastic force of the clutch spring is weakened, it can be adjusted by adding a gasket of appropriate thickness in the pit of the parts in contact with the spring. When shimming, it should be noted that the free length (including gasket thickness) of each spring on the same clutch assembly should be consistent. If the spring cannot recover its original elasticity after adding gasket, a new set of springs shall be replaced. Generally, when the spring is used for 2500-3000h, 1-2mm thick gasket should be added to adjust the pressure; after 5000h of service, all springs should be replaced at the same time.

How to deal with the forming of disc spring

How to deal with the disc spring after forming?
(1) After forming, the disc spring must be subjected to heat treatment, namely quenching and tempering, and the quenching times shall not exceed two times. The hardness of disc spring after quenching and tempering must be in the range of 42-52hrc.
(2) For the disc spring after heat treatment, the single side delamination depth of the disc spring shall not exceed 5% of its thickness for the disc spring with the thickness less than 1.2mm, and 3% of the thickness for the disc spring not less than 1.25mm, and the minimum allowable value is 0.06mm.
(3) All disc springs shall be subjected to strong pressure treatment. The treatment method is as follows: one time flattening, the duration is not less than 12h, or short-time flattening, the number of flattening is not less than 5 times, and the flattening force is not less than 2 times of F (F = 0.75h0). The free height of disc spring should be stable after being pressed. Under the test conditions, the free height should be within the specified limit deviation range.
(4) For disc spring under variable load, surface strengthening treatment, such as shot peening, is recommended for inner cone surface.
(5) If necessary, the surface of disc spring shall be treated with anti-corrosion treatment (such as phosphating, oxidation, galvanizing, etc.). The plated disc spring must be dehydrogenated. The plating method should be avoided for the disc spring under variable load.
(6) No burr, crack, scar and other defects are allowed on the surface of disc spring.

Maintenance of the spring tester with single digit display

Maintenance and repair of the spring tester with single digit display:
1、 The validity period of calibration of indication error of spring testing machine is one year under normal use conditions.
2、 When the spring testing machine is used, especially when unloading, do not let go of it, so as to avoid severe vibration and affect the accuracy of the testing machine.
3、 The lifting rack and each pressure injection oil cup of the testing machine should be lubricated frequently
4、 The validity period of calibration of indication error of spring testing machine is one year under normal use conditions.
5、 When the spring testing machine is used, especially when unloading, do not let go of it, so as to avoid severe vibration and affect the accuracy of the testing machine.
6、 The lifting rack and each pressure injection oil cup of the testing machine should be filled with lubricating oil frequently.
7、 After using, the testing machine should be covered with machine clothes to prevent dust from falling into the machine.
8、 In order to protect personal safety, the testing machine should be properly grounded.

Introduction of wave spring

Wave spring is short for wave spring. It is a thin annular elastic metal component composed of several wave peaks and troughs. The product is made of high-quality spring steel 65Mn
(60Si2MnA / 50CrVA / 0cr17ni7al / SUS304), after special heat treatment and according to specific conditions, the hardness is generally controlled between hrc44-55, the surface is blackened and has good elasticity.
Wave spring is widely used in motor, textile machinery, hydraulic equipment, automobile and other industries. It is mainly installed in the bearing chamber or hole suitable for the specification (nominal size). The installation space is very small. It has the special function of reducing noise and vibration.
The wave spring is divided into WS series and WSS series.
Ws series wave spring
Ws series is continuous winding wave crest interleaving wave spring. The characteristic of this series of spring is that it can provide ideal elastic force in small installation space, and save 50% space than general spiral spring
WSS series wave spring
WSS series is wave crest interleaved corrugated spring with flat ring. In addition to the advantages of WS wave spring, the spring has flat rings at both ends, which is equivalent to adding two washers. Therefore, the spring’s elastic force is more uniform in the process of use. It is especially suitable for two end faces with holes in the installation space. The wave crest of WS type is easy to fall into the hole and cannot be used

Spring in the selection of processing equipment for attention

Several key equipments are introduced as follows:
1. Online flaw detector: imported equipment is generally used to detect wire defects online, find and mark them immediately, and manually detect them after the coil spring is formed.
2. Coil spring: because it works 24 hours a day for a long time, the spring coiling machine is the key equipment for dimensional accuracy. Generally, CNC four axis computerized spring coiling machine with good quality, good wear resistance and high precision is selected. For the springs with the above technical parameters, the production efficiency is more than 35 pieces / min. afios spring coiler is the preferred configuration, and Taiwan machine and Korean machine are also used, which have low investment cost and quick effect, The accuracy can also be well guaranteed if the working time is fixed.
3. Tempering furnace: the maximum temperature is 500oC, and the tempering temperature can be set arbitrarily according to the needs, and the time of the mesh belt in the heating area can also be arbitrarily set according to the needs, so as to meet the processing requirements of different kinds of spring tempering. The domestic tempering furnace can meet the requirements.
4. Spring end grinder: This equipment is one of the most important equipment in the production line, and it is the key equipment to ensure the accuracy. It is generally imported from British bent company, the United States and Germany. The spring is automatically fed into the feeding plate by the feeding machine for rough grinding and fine grinding respectively. It automatically completes the grinding process and enters the next process.
5. Shot peening machine: the on-line rail through type shot peening machine can meet the requirements of automatic production line. The spring is fed by conveyor belt and shot peened by nozzles in multiple directions to ensure the coverage rate of shot peening ≥ 98%. In order to improve the service life, most parts in the shot peening area are imported high wear-resistant materials.
6. Hot press setting machine: in order to increase the stability of spring and reduce the influence of relaxation and creep on the elastic properties, many valve springs have the process of hot pressing. The spring is sent to the furnace by the conveyor belt and held for a period of time, and then applied a certain force to press the coil. After completion, it is sent to the next process. The heating temperature, time and time are adjustable.
7. Load sorter: at present, the supply requirement of most valve springs is 100% load test and sorting. This equipment is the most important and the only quality inspection and guarantee equipment in the whole automation line. It requires high test precision and stable performance, and can still maintain its test accuracy and correct sorting after 24-hour operation every day. Therefore, it is generally imported (such as Moyer company of the United States and Germany The equipment is responsible for this task. For example, the full-automatic load sorter in the United States can test P1, P2 and P3 at the same time, and sort them according to the test results. At most, it can be sorted in five channels and grouped in the qualified area, which greatly meets the requirements of the international spring market.

Notes on the use of metal stamping parts

1、 Before the installation and use of stretching hardware stamping parts, it is necessary to strictly check and remove the dirt, and carefully check whether the guide sleeve and die of the stretching stamping parts are well lubricated.
2、 Regularly check the turntable of punch press and die mounting base to ensure the coaxial accuracy of upper and lower turntables.
3、 According to the installation procedure of the die, install the punch and die on the turntable to ensure the consistent direction of the convex and concave drawing stamping parts, especially for the drawing stamping parts with direction requirements (non-circular and square), pay more attention to prevent wrong installation and reverse installation.
4、 When the punch and die edge wear of drawing stamping parts, they should be stopped in time and sharpened in time, otherwise the wear degree of die edge will be rapidly expanded, the wear of die will be accelerated, and the quality and life of die will be reduced.
5、 The stamping personnel should use soft metal (such as copper, aluminum, etc.) to make operation tools when installing the mold, so as to prevent damage to the stretching stamping parts when knocking and smashing during the installation process.
6、 In order to ensure the service life of the drawing stamping parts, the spring of the die should be replaced regularly to prevent the spring fatigue damage from affecting the use of the drawing stamping parts.
In addition to the reasonable die structure, ultra-high manufacturing accuracy, good heat treatment effect, correct selection of punch and installation accuracy of stretch stamping parts, the service life of drawing stamping parts depends on the proper use, maintenance and maintenance of the die

Elastic action of tension spring

Tension spring: describes the function of tension spring and two characteristics of liquid filling inside
Tension spring is a kind of rubber fiber bellows with precise design. It does not provide force or support load. Instead, compressed air is filled into it by air compressor to realize force transmission and elastic effect. According to the requirements of travel, the tension spring is generally designed to be 1-3 curves, and can be designed and manufactured into 4 or more curves or more when necessary. Under certain conditions, two tension springs can be used in combination.

The tensile spring has nonlinear characteristics, its stiffness changes with the load, so its natural frequency almost remains unchanged under any load, so that the spring device has almost unchanged characteristics; it has good performance of absorbing high-frequency vibration and sound insulation; it can bear both axial and radial loads, and can obtain different bearing capacity by adjusting internal pressure. Therefore, it can meet the needs of various loads.

In the effective stroke, the stiffness, height, cavity volume and bearing capacity of the tension spring are adjusted by increasing or decreasing the inflation pressure. At the same time, its stiffness, height, cavity volume and bearing capacity will change smoothly and periodically with the increase or decrease of load, so as to realize the flexible transmission of bearing capacity, the effective adjustment of stroke and the efficient control of vibration amplitude and load. An additional air chamber can be added to realize automatic adjustment.

The tension spring can be filled with compressed air, nitrogen or water. If water is used to fill the air spring, the anti rust layer should be added to protect the end cover.
There are two characteristics of liquid filling in the tension spring
1. Reduce the gas volume inside the spring, so as to increase the natural frequency of the spring.
2. Because water is an incompressible medium, it can be accurately positioned.

Tension spring pressure
1. According to our experience, the maximum working pressure of standard tension spring is 0.7 MPa.
2. The maximum pressure of high strength (four layer skeleton layer) tensile spring is 1.25 MPa.
We recommend a safety factor of 2.5 times between the maximum internal air pressure and the rupture pressure. Therefore, for example, if a pressure of 0.7 MPa is required, the rupture pressure should be 1.75 MPa or more. The rupture pressure of the spring decreases with the increase of the height. Therefore, there are two determining factors, the maximum height of elongation and the internal pressure at this point.

Analysis of the future market of metal stamping parts

The metal stamping parts have become the future business opportunities of hardware market. Dongguan qiangdong hardware stamping parts factory has triggered the following thinking from the recent actions of individual enterprises:
With the aggravation of the market competition pressure of automatic lathe parts, most hardware factories are in the production, the profit space of each stage of the industrial chain is compressed, and the space of price reduction is decreasing day by day. After the increase of electricity price, the production cost of the hardware factory increases, and it is difficult to transfer it to the downstream.


The profit space of Dongguan Hardware Factory is further squeezed. The vicious circle of industrial chain development leads many hardware factories to realize that if they want to make long-term development and do a good job in the market, they must choose a new battlefield. At the same time, price competition alone can not establish the core competitiveness, which is not the direction of long-term development, so as to explore a new development path. At the same time, it is necessary to strengthen the technological innovation and quality improvement of products. To establish a new business principle to ensure the sustainable development of enterprises.

At the same time, a considerable number of cities, as the market for land sales, are not only large in quantity and low in grade, but also comprehensive in nature. As a result, competition intensifies, development is restricted, and reshuffle is inevitable. We are very optimistic about a small number of specialized markets with national and international characteristics, which are local These professional markets not only have large market space, but also have a good combination with local industries. The support of local governments is far greater than that of other types of professional markets.

In addition to its industrial cluster area, in the development of other areas, we can see that the development of the first tier cities is still mature, no matter which generation of market will have the corresponding business scale. But relatively speaking, the development of the second and third tier cities is still lacking. In the next three to five years, with the deepening of urban planning, I believe it will also drive the development of hardware channels in secondary and tertiary cities. If enterprises want to develop agents, they may as well learn from Shida tools and establish their own stores as soon as possible. It might be a good way to get rich.

Anti corrosion spring

Anti corrosion spring products are widely used in: probes, motorcycles, computers, automobiles, electronics, electrical appliances, toys, computers, lighting, digital cameras, home appliances and other industries.
Chemical corrosion of spring is small and slow, while electrochemical corrosion is main and common. But generally speaking, chemical corrosion and electrochemical corrosion exist at the same time.
If the spring is in contact with electrolyte solution, the corrosion caused by the action of micro cell is called electrochemical corrosion. For example, the spring is in contact with acid or salt solution, which is electrolyte. The electrode with different potential difference is formed due to defects or impurities on the surface of spring, so that the spring is continuously subjected to electrolytic corrosion; Another example is that the spring is in a humid atmosphere, because the water vapor in the atmosphere condenses into water film or water droplets on the spring surface, and the corrosive gases in the atmosphere (such as sulfur dioxide and hydrogen sulfide in industrial waste gas or salt fog in the marine atmosphere) dissolve in the water film or water droplets to form electrolyte.

Causes of defects in spring post treatment and preventive measures

Defect 1: decarburization
Influence on spring performance: low fatigue life
The causes of the defects are as follows: 1. The air furnace is heated and quenched without protective gas; 2. The deoxidization in salt bath is not complete
Preventive measures: 1. Air furnace heating and quenching should be protected by protective gas or drop of organic solution: when heating in salt bath furnace, the salt bath should be deoxidized, and the mass fraction of impurity Bao should be less than 0.2%. 2. Strengthen the surface quality inspection of raw materials
Defect 2: insufficient hardness after quenching
Impact on spring performance: residual deformation, reduce service life
The causes of the defects are as follows: 1. More non martensitic structure; 2. Ferrite in the core; 3. Low quenching temperature; 4. Poor cooling capacity of quenching medium
Preventive measures: 1. Select steel with good hardenability; 2. Improve the cooling capacity of quenching medium; 3. The temperature of spring entering into quenching medium should be above Ar3; 4. Properly raise the quenching heating temperature; 5. Strengthen metallographic examination after quenching
Defect 3: overheating
Effect on spring performance: coarse grains and increased brittleness
The causes of the defects are: 1. The quenching heating temperature is too high; 2. The hot forming temperature is too high
Preventive measures: 1. Heating and quenching according to the correct temperature of process test; 2. Reducing the hot forming temperature properly; 3. Strengthening the calibration of instruments to ensure the accuracy of temperature measurement
Defect 4: cracking
Influence on spring performance: brittleness increases and service life is seriously reduced
Causes of defects: 1. High heating temperature or cooling capacity of quenching medium; 2. Surface decarburization; 3. Delayed tempering
Preventive measures: quenching heating temperature. 1. Strictly control 2. Austempering or martensite step quenching; 3. Cooling to 250-300? C in quenching medium; 4. Tempering immediately after quenching.