Typical uses of stainless steel

Most of the long-term requirements of maintaining the original appearance of the building. In determining to choose the type of stainless steel, the main consideration is the aesthetic standards required by the system to be used to clean the corrosion and the location of the atmosphere. However, a growing number of other applications, or just looking for the integrity of the structure is not permeable. For example, industrial building roof and side walls. In these applications, the construction cost of ownership may be more important than the aesthetic, the surface is not very clean and can be. Effect of using 304 stainless steel in dry indoor environment is quite good.

However, in rural and urban outdoors in order to maintain their appearance, they need regular cleaning. In heavily polluted industrial areas and coastal areas, the surface will be very dirty, and even rust. But to get the aesthetic effect of the outdoor environment, it requires the use of nickel-containing stainless steel. So, 304 stainless steel is widely used in curtain wall, side walls, roofs and other construction purposes, but in severe erosion of industrial or marine atmosphere, the best use of 316 stainless steel. There are several design criteria are included in the 304 and 316 stainless steel.

Because “duplex” 2205 has already good resistance to atmospheric corrosion and high tensile strength and elastic limit of integration, so that the European criteria also included the steel. Product shape, in fact, stainless steel is the whole shape and size of the standard metal manufacturing, and there are many special shapes. The most commonly used products are made with sheet and strip, and plate production with special products, for example, the production of hot-rolled structural steel and structural steel extrusion. And there are round, oval, square, rectangular and hexagonal welded or seamless steel tubes and other forms of products, including profiles, rods, wire and castings. In order to meet the aesthetic requirements of architects, has developed a wide variety of commercial surface processing.

Hydraulic gear pump failure ten Remedy

Remedy:

(1) unloading tank must be installed in the sleeve on the side of the low pressure chamber to eliminate harmful dead volume when closing gear,

(2) Before pressed into self-tight seal, should be coated with a layer of lubricant on the surface, but also pay attention to the resistance of the oil toward the edge of the front cover, can not hold against,

(3) “right-handed” pump can not be installed in the “L” machine, otherwise it will punch a bad seal,

(4) Before loading the pump cover, pour a small amount of oil required to pump housing, and turned by hand gear,

(5) Before the gear pump cover is not installed, tighten the bolts, check the clearance between the pump cover and pump, is between 0.3 ~ 0.6mm, if the gap is too small, you should replace the big ring and relief items. Hydraulic pump installed, should be flexible rotation without catching phenomenon.

(6) according to the season to add or replace grades of oil to meet the requirements of the provisions of the oil at the surface. Remove foreign object inside the tubing, tighten the bolt or nut joints,

(7) the replacement of worn gear pump or pump sleeve, slight wear at the flat end mill will smooth its roughness tolerance 0.03mm, the sleeve on the end face of the pump below the plane (normal is less than 2.5 to 2.6 mm), such as the ultra-poor should be added in the next 0.1 ~ 0.2mm copper sleeve to compensate, the installation should be put into the sleeve at the rear axle,

(8) unloading pieces and sealing ring must be installed in the inlet chamber, two sleeves in order to maintain balance. Unloading piece seal ring should have a preload amount of 0.5mm,

(9) the replacement of aging or damaged oil seal or “O” ring gasket,

(10) while the guide wire should be able to stretch the upper, lower sleeve toward the rotational direction of the driven gear by a small angle of twist, so that the main, two driven gear sleeve machining plane close fit

On the application of hydraulic couplings

Large-scale machinery and equipment for the two-axis adjustment more difficult, you should choose to use durable and easy replacement of wearing parts couplings. Metal elastic element of general than non-metallic flexible coupling flexible coupling elastic element long life. Require lubrication and the use of non-durable sealing couplings, will increase maintenance. For long-term continuous operation and high cost of occasions, such as China’s metallurgical enterprises in the high-speed end mill drive system, now widely used in the gear coupling, gear coupling Although theoretically transmit torque, but it must be in lubrication and sealing durable good condition to work.

And the need to regularly check the condition of the seal, oil or grease injection, maintenance workload, increased aid work, reducing the effective working hours, affecting production efficiency. International industrial countries have common use long life, no lubrication and maintenance diaphragm coupling along replace drum gear coupling, not only improve economic efficiency, but also purify the work environment. In the selection of the mill drive system developed by knockout elastic coupling and flexible coupling segments, not only has the advantage of diaphragm couplings, and a good buffer damping effect, the price is cheaper.

General Machine Components category couplings are used to join two different bodies axis (master axis and slave axis) so that co-rotating mechanical parts to transmit torque.

Explain some widely used on coupling: coupling by elastic deformation of the diaphragm to compensate for the relative displacement of the two axes associated, is a high performance metal elastic element flexible coupling, no lubrication, more compact structure high strength, long life, no rotation gap, independent of temperature and oil slicks, with acid, alkali, corrosion resistant, suitable for high temperature, high speed, there is shaft drive corrosive environmental conditions, and is widely used in shaft drive various mechanical devices, such as pumps (especially power, chemical pumps), fans, compressors, hydraulic machinery, petroleum machinery, printing machinery, textile machinery, chemical machinery, mining machinery, metallurgical machinery, aviation (straight l aircraft), ship speed drivetrain, after balancing for high-speed drive shafts have been more common.

Hydraulic gear pump regulation of safe operation

1. Ground power, chassis ground wire must check the wiring insulation, before commissioning.

2. Before running the high-pressure gear pump should release all the oil control valve, and then start the gear pump, to be empty load is operating normally, and then return valve closed, and gradually screwed into the valve stem oil, increasing the load, and Note that the pressure gauge is normal.

3. gear pump stops working, you should first return valve slowly release until the pressure gauge and slowly return to zero before breaking jack tubing connector nut. Non-removable tubing or pressure gauges at the load.

4. The double-acting jack with gear oil pump, oil at the same time using two-way dual-coupled gear pump is appropriate.

5. The oil must be resistant to high pressure rubber tube, the working pressure shall not exceed the rated maximum hydraulic oil or gear oil pump of the actual work. Tubing length should not be less than 2.5m. When a gear pump driven by two jacks, tubing size should be consistent.

6. gear pumps and jacks to use the provisions of the working oil oil number, usually on the 10th or the 20th machinery oil, can also be used hydraulic oil, other similar nature, such as transformer oil. The oil must be poured into the tank through a filter. Often used when the filter once a month, the tank should be cleaned regularly. General should keep the oil level in the tank is about 85%, should be less timely complements the original pump oil should be the same number of oil. Oil tank should generally be within 10 ~ 40 ℃ is appropriate, should not be used at negative temperature.

7. Avoid bending the tubing at the operating pressure. Gear pumps and jacks to connect the fuel tank should be kept clean, the dam is not used with screws to prevent sediment entering, gear pumps and jacks exposed nipple nut use sealed to prevent dust. Debris into the machine. After daily use, you should wipe the gear pump, remove grease consider oil on copper wire cloth.

8. gear pumps should not be at work overload, safety equipment shall be rated hydraulic pressure adjustment, non-arbitrary adjustments.

How should maintain pressure gear pump

1. Repair the pump housing cavity pump housing cavity after abrasion, in general, casement law cavity repair, upcoming cavity Boring big set with cast iron or steel liner after sets. After the casement, the cavity lining 5, seat repairs: pressure limiting valve and plunger valve has two ball valves. After the spherical seat wear can be a ball on the seat, and then gently tap the ball with a metal rod until the ball and seat snug. Such as seat badly worn hinges can be trimmed to grind marks, then the law to make it close together. After the plunger seat wear, you can put a little sand valve grinding until snug.

2. The pump cover repairs, repair work plane: If the pump cover work wear smaller plane can be used hand-grinding method to eliminate signs of wear, that put a little sand valve on the platform or thick glass, and then carried on top of the pump cover grind until eliminate signs of wear, work surface until smooth. When the pump is working flat cover more than 0.1 mm wear depth, should take the first turning grinding way to repair.

3. Repair gear pump drive shaft and bushing wear, with the gap increases, will affect the fuel pump. If this method can be used to repair the drive shaft or sleeve resume its normal with the gap. If the drive shaft wear light, simply press out the old bushings replaced after standard size bushing, with the gap can be restored to the permitted range. If the driving shaft and bushing wear serious and with the gap seriously overweight, not only to replace the bushings, and a drive shaft also applied chrome or vibration welding method will increase its diameter, and then grinding to a standard size, recovery and bushes coordination requirements.

4. housing repair, crack the shell of available nickel-copper rod casting 508 welding. Weld must close and Yuan pores, combined with the pump cover face flatness error of less than 0.05 mm.

5. Wear repair, after the drive shaft bushing bore wear, available reaming method to eliminate signs of wear, and is equipped with a corresponding increase to the size of the bush. Also driven shaft bore wear reaming method to eliminate signs of wear, and then press the actual size of the hole after reaming preparation of the driven shaft.

Stainless steel products production materials

Because of the different uses of each product, its process and materials quality requirements are also different. Generally different stainless steel products, which require raw materials thickness tolerances vary, like second-class cutlery and mug, etc., generally require a higher thickness tolerances, -3 to 5%, and a thickness tolerance tableware General requirements – 5% -10% steel such requests, hotels with a freezer timber thickness tolerance requirements for 8%, dealers thickness tolerance requirements generally between 4% to 6%. At the same time export products will lead to different customers in different thickness tolerance requirements for raw materials. Generally higher exports of customers thickness tolerance requirements, while domestic enterprises thickness tolerance requirements are relatively low (mostly because of cost considerations), some customers even require -15%.

①DDQ (deep drawing quality) material: refers to the material used for deep drawing (punching) use, that is, we called a soft material, the main characteristics of this material is higher elongation (≧ 53%), compared with the hardness low (≦ 170%), internal grain grading between 7.0 to 8.0, excellent deep drawing properties. Many production thermos pot class enterprises, processing their products generally have higher than (BLANKING SIZE / products in diameter), which processed more than 3.0,1.96,2.13,1.98 respectively. SUS304DDQ timber is mainly used for processing these requests higher than that of the product, of course, the processing ratio of more than 2.0 products are generally subject to stretch a few times to complete. If the extension of terms of raw materials reach it, in the processing of deep drawing products product cracks easily, pull wear phenomenon, affecting the rate of qualified products, of course, will increase the cost of manufacturers;

② General Material: mainly used for purposes outside except DDQ material characteristics of this material is relatively low elongation (≧ 45%), while the hardness is relatively high (≦ 180HB), internal grain grade of 8.0 to 9.0 Rooms, compared with DDQ timber, its performance relative somewhat less deep drawing, it is mainly used in the products can be obtained without thrust, like a class tableware spoon, spoon, fork, electrical appliances, steel uses. But it is compared with DDQ material has an advantage that BQ relatively good, mainly because of its hardness slightly higher reason.
Stainless steel sheet is an inexpensive material, but customers of its very high surface quality requirements. Stainless steel sheet in the production process inevitably there will be a variety of defects, such as scratches, pits, sand hole, dark lines, creases, pollution, etc., so that its surface quality, such as scratches, creases, etc. These defects are advanced materials allowed, and pitting, sand holes this defect in the spoon, spoon, fork, the production is never allowed because it is difficult to throw away when polishing. Required depending on the degree and frequency of surface defects of various kinds, to determine its quality level table, thereby to determine the product level.

Stainless steel structural components

Increase the corrosion resistance of stainless steel with the carbon content decreases, and therefore, most of the lower carbon stainless steel volume, to a maximum of 1.2%, and some steel ωc (carbon content), and even less than 0.03% (e.g. 00Cr12 ). Stainless steel is the main alloying elements Cr (chromium), only when the Cr content reaches a certain value, there is corrosion resistance of steel. Therefore, stainless steel is generally Cr (chromium) content of at least 10.5%. Stainless steel also contains Ni, Ti, Mn, N, Nb, Mo, Si, Cu and other elements.

Hydraulic gear pump regulation of safe operation

1. Ground power, chassis ground wire must check the wiring insulation, before commissioning.

2. Before running the high-pressure gear pump should release all the oil control valve, and then start the gear pump, to be empty load is operating normally, and then return valve closed, and gradually screwed into the valve stem oil, increasing the load, and Note that the pressure gauge is normal.

3. gear pump stops working, you should first return valve slowly release until the pressure gauge and slowly return to zero before breaking jack tubing connector nut. Non-removable tubing or pressure gauges at the load.

4. The double-acting jack with gear oil pump, oil at the same time using two-way dual-coupled gear pump is appropriate.

5. The oil must be resistant to high pressure rubber tube, the working pressure shall not exceed the rated maximum hydraulic oil or gear oil pump of the actual work. Tubing length should not be less than 2.5m. When a gear pump driven by two jacks, tubing size should be consistent.

6. gear pumps and jacks to use the provisions of the working oil oil number, usually on the 10th or the 20th machinery oil, can also be used hydraulic oil, other similar nature, such as transformer oil. The oil must be poured into the tank through a filter. Often used when the filter once a month, the tank should be cleaned regularly. General should keep the oil level in the tank is about 85%, should be less timely complements the original pump oil should be the same number of oil. Oil tank should generally be within 10 ~ 40 ℃ is appropriate, should not be used at negative temperature.

7. Avoid bending the tubing at the operating pressure. Gear pumps and jacks to connect the fuel tank should be kept clean, the dam is not used with screws to prevent sediment entering, gear pumps and jacks exposed nipple nut use sealed to prevent dust. Debris into the machine. After daily use, you should wipe the gear pump, remove grease consider oil on copper wire cloth.

8. gear pumps should not be at work overload, safety equipment shall be rated hydraulic pressure adjustment, non-arbitrary adjustments.

What are the conditions of the hydraulic pump to work to meet?

Under what conditions to meet in order to make the pump normally work?

1, should have to have a sealed volume. If the volume is not enough seal, it will not be enough for the oil pressure into energy, it can not be converted into energy, the hydraulic pump to move up.

2, sealed volume can alternate with each other. During continuous operation of the pump, when the volume of the oil chamber that it must continue to slowly increase from small to form a vacuum chamber oil, then the oil tank can be inhaled; when the oil chamber volume from large slowly When reduced, the oil will be pressed into sealing working oil chamber, so that the internal pressure was increased, the oil pressure depends on the output when the input from the pump by the resistance size.

3, the device should be equipped with flow means, when the suction pump automatically in communication with the reservoir, and when the oil pressure supply line communicated with the reservoir while automatically cut off.

4, when the suction air to circulate inside the tank with each other, is a prerequisite to achieve oil-absorbing.

People working in the mechanical factory know, to make the large machine started up production work, it is first of all have to work the pump in order to promote the production and operation of the machine, hydraulic pump would be tantamount to the heart of those behemoths, led the other bodies of the machine work. When the pump this “heart” problems can not operate normally, those big machines will not be forced to stop work.

How to prolong the service life of hydraulic piston pump method

A pump no overload design technology applications: In the conventional centrifugal pump, power is always increases with increasing flow, that is, a power curve is increased with increase in the flow rate curve, which pump use will bring a problem: when the pump is operating at design point, in general, the pump motor power is less than the rated power, the use of this pump is safe; but when the pump head is reduced, the flow will increase (from the pump performance curve can be seen), the power increases. When the traffic flow exceeds the design point and arrived a certain value, the pump motor input power may exceed the rated power and the formation of motor overload and burnout. Motor overload or maintenance operation of the system to suspend the action of the pump rotation; or failure to maintain the system so that the motor burned. Pump head lower than the design point lift conditions used in practice is often encounter a situation is when the pump selection, pump head selected too high, while the practice is to reduce the use of the pump head use; the other situation is that in the use of the pump operating point is certainly not very good, in other words the pump flow requirements often stop conditioning; there is a situation that needs frequent changes location using the pump.

Second, these three conditions were unfamiliar overload may affect the pump using the pump robustness. Be able to say, for there is no full head pump characteristics (including submersible sewage pumps), its scope of application would have been restricted to a large extent on. The so-called full head properties (also known as non-overload characteristics) refers to the power curve with the increase in traffic and the speed is very slow rise, more desirable when the flow reaches a certain value, the power not only will not rise again, it will be landing, that the power curve is a hump in the curve, if so, we simply select the motor rated power hump point slightly beyond the power value, then at zero flow to the entire range of the maximum flow rate, and you both in that running on an operating point, the pump will not exceed the power leaving the pump motor power overload on the pump with this performance, whether it is the selection or use, will be very convenient and secure. Also worthy of motor power also need large equipment costs can be considerable parsimonious. We deputy leaf turns body sealing technology and pump power without overloading design technology used in submersible sewage pump, the greater progress of the pump seal securely and carrying capacity, extending the service life of the pump.

Effectively extending the service life of submersible sewage pump submersible sewage pump approach has increasingly been focusing on people, use the range more widely, from simple walks water used to be able to convey to today’s variety of domestic sewage, industrial waste, construction sites and drainage, liquid feed and so on. Plays a very important role in municipal engineering, industry, hospitals, buildings, hotels, water conservancy and other industries in the establishment. About submersible sewage pumps for the most critical issue is the robustness problem – effectively extend the service life of the pump problem. Due to the use of submersible sewage pumps are places in the liquid; walked the media are mixed liquid containing solid materials; pump and motor are very close; pump for vertical layout, with the impeller rotating parts by weight of water pressure to accept the same direction. These problems have made the request in a sealed submersible sewage pumps, motors carrying capacity, bearing arrangement and selection and other aspects than ordinary sewage pump higher. In order to effectively extend the life of submersible sewage pumps, submersible sewage system set up to maintain the pump is necessary, it can effectively maintain the safe operation of the electric pump. But the key is not the problem, just to maintain the system in a method to compensate the pump after the onset of illnesses, is a passive way to match. The key issue is the question should start from the basic, thorough treatment of pump seals, overload, etc., this is a more proactive approach. For this reason we took turns body vice leaves power sealing technology and pump design technology used without overload submersible sewage pumps, the great progress of the pump seal securely and carrying capacity, extending the service life of the pump. Imported pumps, valves Custer wine

Third, the application of Dynamic deputy leaf turns sealing technology: the so-called sub-leaf turns body dynamic seal means that after the pump impeller cover the back near the coaxial in the opposite direction means an open impeller. When the pump is working, vice impeller rotates together with the pump shaft, impeller deputy liquid will rotate with the rotation of the liquid will produce an outward centripetal force, the centripetal force on the one hand against the flow of fluid mechanical seal, reducing the mechanical pressure seal at. On the other hand to prevent the media of solid particles into the mechanical seal friction, the reduction of the mechanical seal grinding block wear and prolong their use life. But deputy impeller sealing effect, but also can play a role in reducing the axial force, axial force composed mainly by the liquid pressure differential forces on the impeller and the rotating partial gravity sewage pump, which the direction of action of the two forces are the same, are added together is formed by two forces. As can be seen, in the same situation a complete performance parameters, axial force submersible sewage pump is larger than the average horizontal pumps, vertical pumps and balanced than the harder difficulty. So submersible sewage pumps, bearings easily damage their cause is the axial force has a great relationship. And if the installation of the direction of Vice impeller, the impeller fluid pressure acting on the deputy force is with these two forces together to the contrary, this can offset a partial axial force, also played a role in extending bearing life. But the use of auxiliary impeller sealing system also has a flaw, it is in the secondary impeller to spend a local energy, common in about 3%, but simply designed, complete partial loss can reduce this to a minimum.