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Cleaning and general use of ultrasonic mechanical parts

Ultrasonic cleaning machine for machinery industry parts cleaning: (cleaning attachments: cutting oil, abrasive particles, iron chips, dust, fingerprints)

Removal of rust-proof grease; Cleaning of measuring tools; Removal of oil and rust from mechanical parts; Removal of engine, engine parts, gearbox, shock absorber, bearing bush, nozzle, cylinder block, valve body, carburetor and automobile parts and chassis before painting, removing rust and phosphating; Cleaning of filter, piston fittings, filter screen, etc. Precision mechanical parts, compressor parts, camera parts, bearings, hardware parts, molds and so on.

General methods of ultrasonic cleaning

1. Connect the temperature control sensor signal line, ultrasonic drive line, heater control line and other circuits between the electronic control cabinet and the host computer according to the installation instructions of the ultrasonic cleaner, and connect 380VAC power supply, install the upper water pipe, discharge water pipe and overflow discharge pipe of the cleaner.

2. clean the pond with ultrasonic wave.

Add proper amount of clean water to the cleaning pool, and the height of the liquid level should be as high as immersing the parts to be cleaned, generally not more than three-quarters of the cleaning pool.

3. ultrasonic cleaning heating

Start the electric heating switch and point the white scale line on the water temperature adjusting knob to the appropriate temperature (about 60 C). The maximum temperature of the cleaning agent should not exceed 70 degrees during the use of the washing machine.

4. cleaning agent is added to the ultrasonic cleaner.

When the water temperature rises to about 40, UC-O3 parts cleaning agent is added to the cleaning pool (usually about 5 kg at a time), and the clear water is agitated slowly to dissolve fully (at this time, the ultrasonic wave can be started or the air-blowing device can be opened for stirring).

5. pretreatment of ultrasonic cleaning machine

Before cleaning, it is better to use bamboo knife to clean the dirt on the surface of parts (for example, there will be a lot of dust on the outer surface of the dust shield, and the parts of cylinder block will accumulate a lot of thick and easy-to-remove sludge at the change of the curve of the outer shell) so as to prolong the service life of the cleaning fluid.

Ultrasound can carry out precision cleaning, but its ability to treat mud dirt is weak, so pretreatment should try to remove yellow mud or thin mud dirt.

Classification of rotor pumps

Rotor pump is divided into gear pump, screw pump, rotary piston pump (cam pump, Roots pump), flexible impeller pump, sliding vane pump, hose pump, etc.

(1) gear pump

Gear pumps are mainly composed of gear, shaft, pump body, pump cover, bearing sleeve, shaft end seal and so on. A revolving pump that relies on the change and movement of the working volume between the pump body and the meshing gears to transfer liquid or pressurize it. Gear pumps have two types of external and internal meshing. External meshing gear pump is divided into double gear pump, three gear pump and five gear pump, external meshing double gear pump is the most commonly used. A pair of meshing gears and pump bodies separate the suction cavity from the discharge chamber. When the gear rotates, the volume between the teeth at the side of the suction cavity increases gradually, the pressure decreases, and the liquid enters the teeth under the action of pressure difference. As the gear rotates, the fluid between the teeth is carried to the discharge chamber. At this time, the volume between the teeth of the cavity side gear is gradually reduced, and the liquid is discharged.

(2) screw pump

The screw pump consists of a pump housing and one or more screws. The working principle of twin-screw pump is very similar to gear pump. It relies on intermeshing screw to suck liquid. Screw pump is divided into single screw pump, twin-screw pump and three-screw pump according to the number of screw, of which twin-screw pump has two types: closed and non-closed.

(3) rotary piston pump

There are many kinds of rotary piston pumps, the most commonly used ones are cam pumps and Roots pumps.

Cam pump is a multi-purpose two-way volumetric pump, is one of the most advanced international fluid conveying equipment, it is using two synchronous rotor, the rotor is driven by a pair of external synchronous gears, the rotor in the drive shaft driven by synchronous reverse rotation, rotor and rotor-pump body does not contact each other. Instead, it forms a clearance line or a face seal, which constitutes a higher vacuum and discharge pressure, especially suitable for the transportation of food, medicine, corrosive and high viscosity media.

Roots pump and cam pump structure is similar, the difference is that the liquid seal should also be formed between the rotor, the large pump is mostly simply supported layout, its processing is simpler than the cam pump, the working pressure is lower than the cam pump.

(4) flexible impeller pump

The flexible impeller pump is a volumetric rotor pump. The flexible impeller pump is composed of a flexible impeller, pump body, mechanical seal and rotating shaft made of rubber. When the impeller rotates away from the eccentric section of the pump shell, the flexible impeller blade extends to create a vacuum, and the liquid is sucked into the pump. With the impeller rotating, the liquid then reaches the discharge side from the suction side. When the impeller blade contacts with the eccentric section of the pump shell, the working volume changes, and the liquid is discharged smoothly out of the pump.

(5) slide pump

The rotor with radial groove is installed in the pump body with eccentric stator. The slider is located in the radial groove of the rotor. The slider can be two or more pieces. When the rotor rotates, the slider is thrown out of the rotor body and slides along the inner surface of the stator. These slides and stators constitute a sealed cavity with the eccentric cavity gradually increased, continue to rotate, the cavity reduced to zero, and filled with the rotor, slides between the cavity began to suck in the suction area, and then pressure to the discharge area to complete the liquid delivery process.

Quality product performance of vertical shaft planetary mixer

Vertical axis planetary mixer has high quality product performance, the overall design meets the requirements of uniformity, compact structure, reasonable layout, can adapt to heavy load operation of materials, with good results.

Vertical axis planetary mixer can be targeted to the study of materials, can adapt to the different needs of materials, combined with advanced technology at home and abroad, to achieve the greatest mixing effect of materials, in the transmission of the European advanced reducer can achieve automatic adjustment of working equipment, adapt to the load of materials, save electricity. Yes.

Vertical axis planetary mixer has high quality, strong mixing performance, and can quickly cover the entire mixing drum in a short time. It has large operating area, sufficient mixing space and good mixing effect.

Common problems in the use of sander

The sander will inevitably break down when it works. Most of the minor problems can be solved by us. But if it is not handled properly, the whole project will be delayed and the production cost will be affected. Therefore, this requires the operator to have some understanding of common failures, when similar failures occur, can quickly respond, timely removal.

1, abrasive belt wrinkle: once the belt is wrinkled, it can no longer be used. Generally, it causes three kinds of wrinkles. The first is that the sand roller and the tension roller are not parallel in the vertical plane projection, so the pad should be added at the center supporting cylinder to correct. The two is the wetting and wrinkling of the abrasive belt, which can be dried and dried. Thirdly, the sand machine does not use the surface of the sand roller for a long time to rust rough, sand belt swing difficult to trigger a trend, at this time should be used to remove the roller rust or grinding with fine sand paper;

2. Abrasive belt breakage: Abrasive belt breakage is mainly caused by abrasive belt deviation, or abrasive belt grinding dull not timely replacement, or excessive grinding load, or encountered in the process of grinding hard or abrasive belt itself quality problems. The abrasive belt should be avoided as far as possible, otherwise it may cause fire or explosion. When abnormal roll current occurs in the operating table, it should be observed whether the belt has been worn down, if it is timely replacement;

3. Belt deviation: generally due to improper adjustment, the normal belt swing should be 15-20 mm swing, swing frequency 15-20 times / min, moderate swing speed and swing in and out of the same speed. If in an abnormal state, a long time, may appear deviation phenomenon, especially in the swing in and out of the speed is not consistent, more easily triggered. The deviation of the belt may be caused by the failure of the photoelectric tube, the damage of the swing valve or the swinging cylinder. Dust is not good, high dust concentration will affect the normal work of the tube, and may cause belt deviation.

Working principle of star type unloader

1. Star unloader is often used in pneumatic output system. For pressure output system or negative pressure output system, star unloader can supply material to conveying pipe uniformly and continuously. In order to ensure the pneumatic output pipe gas, solid relatively stable, so that pneumatic conveying can work normally, at the same time, the upper and lower air pressure of the unloader can be partitioned and play a role of gas lock. Therefore, star type discharger is an important component in pneumatic conveying system.

2. When the material in the upper bin is filled in the gap between the blades by self-weight falling, it is discharged at the lower part with the rotation of the blades. Therefore, the star discharger can be discharged quantitatively and continuously.

Three, the star type discharger can be used in the material collection system as the unloading device of the bin. Star unloader is the most advanced unloading device in China. It is often used in the dust removal system as one of the important equipment of the dust removal system. It is especially suitable for dust, small particle materials, by environmental protection, metallurgy, chemical industry, grain, cement, road construction, drying equipment and other industrial projects selected for use.

4. Temperature-resistant type it conveys material temperature up to 280 degrees C both ends of the bearing and impeller has certain isolation, can prevent ultra-fine powder and bearing contact. The temperature of high temperature discharger conveyed material can reach 500 degrees C and connected by chain wheel. There is a certain distance between the reducer and the discharger housing.

Star unloader is composed of rotor impeller, shell, seal, reducer and motor with several blades. Star unloader is also called rotating feeder, gas lock valve, star unloader, star unloader, air shutter and so on.

Types of coupling

The coupling can be divided into two categories: rigid coupling and flexible coupling.

Rigid coupling does not have the ability of cushioning and compensating the relative displacement of the two axes. It requires two axes to be aligned strictly. However, this kind of coupling has the advantages of simple structure, low manufacturing cost, easy assembly and disassembly, easy maintenance, high neutrality of the two axes, large transmission torque and wide application. Commonly used flange coupling, sleeve coupling and clamp coupling.

Flexible couplings can be divided into flexible couplings without elastic elements and flexible couplings with elastic elements. The former one only has the ability to compensate the relative displacement of two axes, but can not cushion and reduce vibration. In addition to compensating the relative displacement of two axes, it also has the function of cushioning and reducing vibration. But the transmitted torque is limited by the strength of elastic element, which is generally inferior to the flexible coupling without elastic element. Spring coupling and reed coupling.

Wax cleaning for stainless steel parts

I. scope of application:
A. is suitable for dewaxing, deoiling and degreasing of metal workpiece after mechanical polishing.
B. is suitable for bulk and large output parts to save wax, remove dirt and save cost.
C, suitable for viscous dry oil cleaning (other methods are difficult to remove).
Function: it can remove the wax layer on the surface of the workpiece quickly and cleanly and cleanly.
Suitable material: suitable for all metals (steel, copper, aluminum, iron…). Polish the wax. Cleaning copper and aluminum parts will not change color.

Two, advantages:
1 remove the dirt and remove dirt quickly, and the effect is good; it can remove thick wax layer.
2 low cost and low cost.
3 all kinds of materials are used to solve the problem of changing color in the market compared to copper and aluminum parts.
4 reduce workers’ labor intensity, high production efficiency and low cost.

Three, service life:
The liquid content of the 1 kg raw liquid will not be lost within the area of 60~80 square meters.

Four. Usage:
1, the degreasing agent is mixed with water, the ratio is 1:95~97 (the concentration is 3%~5%).
2. When the solution is heated to 60~80 degrees, immersion, airflow or ultrasonic cleaning can be used.
3. The general dewaxing time is 5-15 minutes (the user holds the wax layer according to the thickness of the workpiece), if it cooperates with ultrasonic cleaning, the dewaxing effect is better and faster. The effect of heating and waxing is better and faster (the higher the temperature is, the faster the decontamination is).
4. Rinse and dry after the wax.

Passivation solution for stainless steel 304 screws

I. scope of application:
A. “Stainless steel passivation fluid” is mainly suitable for small and medium stainless steel workpieces which are easy to soak (the volume of workpiece is less than 3 cubic meters is recommended, more than 3 cubic meters or batch of small recommended passivation paste)
B. is suitable for processing large quantities and large output parts and saving cost.
C. has special requirements that must be soaked and passivated.
Function: it can effectively improve the corrosion resistance of stainless steel and prolong the service life of the workpiece.
Suitable material: suitable for all 200 and 300 series stainless steel.

Two, characteristics:
1. The liquid medicine can be recycled. The service life of 1 Kg can reach 50-70 square meters. It can effectively reduce the waste of liquid medicine and save more processing cost.
2. Stainless steel passivation solution is more simple to use, just soak in the tank at room temperature can greatly reduce the labor intensity. There is no need for specific processing equipment and strict processing conditions.
3. Passivating solution is a kind of stable reagent, which can not be decomposed, precipitated and transported conveniently. It has a storage period of three years and can be taken as needed.

Three, the area of use:
1 kg of passivation solution will not lose the liquid composition within the area of 50~70 square meters.

Four. Usage:
1. According to the processing conditions of the workpiece, degrease the oil first (can use detergent + cylinder polishing cleaning, white oil, Tian Na Shui, etc.) or use our company’s “normal temperature neutral cleaning agent” direct cleaning), mechanical polishing parts dewaxing first (can use our company’s “general dewaxing cleaning agent”), flushing water to ensure that the surface is clean.
2. pickling or activation (with 3-5% dilute sulfuric acid) pickling for 3-5 minutes (specific time control, mainly to observe the surface of the workpiece not too dark pickling), or directly using our company’s “stainless steel activation liquid” (for 300 series of materials salt fog resistance time requirements less than 72 hours and very clean surface of the workpiece this step can be saved A small batch test.
3., inactivate the passivation solution and use the original solution. The soaking time is more than 30 minutes. It is recommended that 60 minutes (200 hours of general experience of 300 series materials) be soaked. The longer the soaking time is, the better the anti-corrosion performance will be. The longest time is not more than 24 hours.
4. rinsing clean water (not using sewage or natural water), rinsing the surface of the workpiece passivation solution.
5. Finally, soak and rinse with water containing less than 25 PPM chloride ion (pure water or filtered water) for 3 minutes.
6. drying.

Development of gear pumps

Among all kinds of hydraulic gear pumps, hydraulic gear pump has the advantages of simple structure, compactness, small volume, light weight, good self-priming performance, insensitive to pollution, reliable operation, long service life, convenient maintenance, low cost, and because the gear is a symmetrical rotating body, it allows high-speed rotation and other characteristics, widely used. Machine tool industry, shipbuilding industry, aviation engineering, agricultural machinery.

The development of gear pumps is marked by an increase in pressure levels. Early gear pumps, whether axial (gear face direction) or radial (gear circumference direction) are fixed clearance type, the pressure is less than 10 MPa. In the past 30 years, after the efforts of hydraulic workers, such as the use of axial and radial clearance compensation methods, the pressure level of gear pump has been significantly improved, up to 31.5 Mpa, has been squeezed into the medium and high pressure industry, changing the past view that gear pump is only used in low pressure system. The main disadvantage of gear pump is that the pressure pulsation is large and the leakage increases under high pressure. If it can be overcome, it shows that gear pump can not only keep the advantages of easy manufacture and low cost, but also replace some difficult pumps (such as plunger pumps) to further expand the scope of use. This will obviously bring greater technical value and social and economic benefits.

Many countries have made great breakthroughs in the technical research of gear pumps in recent years. In order to ensure reliable sealing between the suction chamber and the pressure chamber of the pump, the pump of Shimazu Seisakusho Company of Japan has set up special grooves in the end cover and embedded elastic sealing strip, which makes the volume efficiency high. Czech developed pumps, driven gear mounted on the ball support to ensure self-centering with the driving wheel, and reduce noise. Saitama Ki’s pumps in Japan have little change in trapped oil volume, thereby reducing pressure pulsation and improving working stability.

The development of gear pumps in China is as follows: 1) The radial clearance and axial clearance of low-pressure gear pumps are fixed, working on the principle of clearance sealing. The BC pump of Shanghai Machine Tool Plant and the CB-B pump of Wuxi Hydraulic Parts Factory belong to this kind of pump. 2) Medium and high pressure pumps are divided into two types according to axial clearance automatic compensation, one is the floating shaft sleeve type, such as the CB series pumps of the Yangtze River Hydraulic Component Plant and the YBC series pumps of Shijiazhuang Coal Mine Machinery Plant; the other is the elastic side plate type structure, such as the CB-BF type pump of Yuci Hydraulic Component Plant. 3) Typical high-pressure gear pumps are the CB-L type gear pumps of the Yangtze River Hydraulic Works. They have balanced structure of axial clearance and radial clearance. CBZ2 series high pressure gear pumps manufactured by Jinan Hydraulic Component Works have been patented in China. Axial compensation and radial tracking compensation are used to reduce the high pressure area and radial force. CBZb series adopts gear axial, radial floating compensation to reduce the inherent radial force of the gear pump. In the case of using rolling bearings, it has reached high pressure. Now it has applied for patents in China, the United States, Japan and other countries.

In recent years, with the increasing output of gear pumps, driven by the development of gear pumps to high pressure and high reliability, gear pump technology in China has made new progress and breakthroughs. Gear pumps are developing towards high integrated modularization, attaching importance to environmental protection, developing zero leakage and low noise components. Threaded cartridge valves are widely used, oil pump noise is significantly reduced, hydraulic pump variable information and intelligent control has been widely used. Products such as Japan, Denmark and the United States have already been sold. Rapidly biodegradable fluids such as benzene oil-based and synthetic ester-based transmission media have been used to reduce pollution. Water hydraulic transmission has been widely valued. The scientific and technological workers in Japan and Finland have done a lot of work. Products have been sold in Japan, Denmark, the United States and other countries. The research on seawater hydraulic pump by Professor Zhou Hua and Li Zhuangyun of Huazhong University of science and technology in China is very meaningful. Pure water hydraulic pump is the most important component in the pure water hydraulic system that has been re developed in recent years. Pure water is compatible with the environment as the medium of the hydraulic pump system. The system simplifies the safety, fireproof energy-saving, economic and health and other green features to meet the needs of sustainable development of mankind. Danish company Danfoss is a typical supplier of water hydraulic pump components, its Nessie series of water hydraulic components have been supplied to the market. The German Hanhinc Gmbh company and the British Fenner company also have a series of water hydraulic pump components supply market. China’s East China University of science and technology has made considerable progress.

CAD design makes manual design become automatic and semi-automatic, especially the popularization and application of CAD / CAM / CAPP make hydraulic technology develop rapidly. Over the past decade, workstations and PCs have been widely used. Overseas, the application of hydraulic CAD plays an important role in improving the design quality, speeding up the design speed and promoting the replacement of hydraulic products. The development of hydraulic CAD technology is more rapid in the 1990s. The next long-term goal of hydraulic technology development is to fully support the whole process of hydraulic products from conceptual design, appearance design, performance design, reliability design to detailed design of parts and components, and to make use of CAD and CAA. (CAE), Computer Aided Process Planning (CAPP), Computer Aided Inspection (CAI), Computer Aided Testing (CAT) and modern management system are integrated to establish a computer manufacturing system, which makes a breakthrough in hydraulic design and manufacturing technology.

Introduction to drilling machine common types of machine tools

Ancient drill – “bow roller”. Drilling technology has a long history. Archaeologists have discovered that in 4000 BC, human beings invented the device for drilling holes. The ancients erected a beam on two pillars, then hung a rotating cone downward from the beam, and then twisted the cone with bowstring to drive the cone to rotate so that it could punch holes in wood and stone. Soon afterwards, a drilling tool called a “wheelbarrow” was designed, which also uses elastic bowstring to rotate the cone.

The first drilling machine (Whitworth, 1862). Before and after 1850, German Marty G Noni first made a twist drill for metal drilling. At the International Fair in London, England, in 1862, Whitworth, an Englishman, exhibited a power-driven drilling machine for iron racks, which became the prototype of modern drilling machines.

Later, a variety of drilling machines appeared one after another, such as rocker drilling machine, drilling machine equipped with automatic tool feeding mechanism, multi-axis drilling machine that can drill multiple holes at the same time. Thanks to improvements in tool materials and drill bits and the use of electric motors, large, high-performance drilling machines were finally made.