Taboo 1

Winter construction carries out hydrostatic testing at negative temperatures.
Consequence: The pipe freezes and breaks due to ice formation inside the pipe during hydro testing.
Measures: Hydrostatic testing should be carried out as much as possible before winter construction, and the water should be blown clean after testing, especially the inside the valves must be completely removed. Otherwise, the valves will rust or even crack. When hydrostatic testing must be carried out in winter, it should be at positive temperatures indoors, and the water should be blown clean after testing.

Taboo 2

The flushing before the completion of the pipeline system is not thorough, and the flow rate and velocity do not meet the pipeline flushing requirements. In cases, water pressure strength tests are used instead of flushing.
Consequences: The water quality does not meet the operational requirements of the pipeline system, which can lead reduced cross-sectional area or blockages in the pipeline.
Measures: Flushing should be carried out with the maximum design flow rate of the system or a water velocity of no less than 3m/s. The flushing is considered合格when the color and transparency of the water at the outlet visually match those at the inlet.

Taboo 3

The sewage pipe, rainwater pipe, and condensate pipe are concealed without undergoing a water-sealing test.

Consequence: It may cause water leakage and result in losses for the user.

Measures: The water-sealing test work should be strictly inspected and accepted according to standards. For underground, ceiling, and inter-pipe concealed installations of sewage, rainwater, and condensate pipes, it must be ensured that they are non-leaking and non-infiltrating.

Taboo 4

During the pipeline system's hydrostatic strength test and tightness test, only the pressure value and water level changes were observed, and the inspection leaks was insufficient.

Consequence: After the pipeline system is put into operation, leakage occurs, affecting normal use.

Measures: When conducting tests on the pipeline system to design requirements and construction specifications, in addition to recording the pressure value or water level changes within the specified time, special attention should be paid to carefully checking for leakage issues.

Taboo 5

The butterfly valve flange is made of ordinary valve flanges.

Consequence: The butterfly valve flange and the ordinary valve flange are different size. Some flanges have smaller inner diameters, while the butterfly valve's valve flap is larger, causing it to be unable to open or forcing it open resulting in valve damage.

Measures: The flange should be processed according to the actual size of the butterfly valve flange.

Taboo 6

During the construction of the building structure, no reserved holes and embedded parts were provided, or the sizes of the reserved holes were too small and the embedded parts were not marked.

Consequences: During the construction of the heating and plumbing works, the building structure had to be chiseled, and even the stressed reinforcing bars were cut, which affected the safety performance of the building.

Measures: Thoroughly familiarize yourself with the construction drawings of the heating and plumbing works. According to the needs of the installation of pipelines and supports and hangers, actively and conscientiously cooperate with the construction of the building structure to reserve holes and embed parts. Specifically, refer to the design requirements and the provisions of the construction specifications.

Taboo 7

Consequences: The misalignment of the pipes not being on the same center line directly affects the welding quality and the appearance quality. When no gap is left at the pipe ends, the groove is not cut for thick-walled pipes, and the width and height of the weld seams do not meet the requirements, the welding will not meet the strength requirements.

Measures: After the pipe ends of the welded pipeline are aligned, the pipes should not be misaligned and should be on the same center line; a gap should be left at the pipe ends; the groove should be cut for thick-walled pipes. In addition, the width and height of the weld seams should be welded in accordance with the requirements of the specifications.

Taboo 8

Pipelines are directly buried in frozen soil or untreated loose soil, the spacing and position of pipeline piers are improper, and even the form of dry-laid bricks is adopted.
Consequence: Due to the unstable support, the pipeline is damaged during the backfilling compaction process, resulting in rework and repair.
Measure: Pipelines shall not be buried in frozen soil or untreated loose soil. The spacing of piers shall meet the requirements of the construction specification. The supports shall be firm, especially at the pipeline joints, which should not bear shear force. Brick piers shall be built with cement mortar to ensure integrity and firmness.

Taboo 9

The expansion bolts for fixing pipeline supports are of inferior quality, the hole diameter for installing expansion bolts is too large, or the expansion bolts are installed on brick walls or even lightweight walls.
Consequence: The pipeline supports become loose, the pipeline deforms, and even falls off.
Measure: Qualified expansion bolts must be selected, and sampling inspection shall be carried out if necessary. The hole diameter for installing expansion bolts should not be larger than 2mm of the outer diameter of the expansion bolt. Expansion bolts should be used on concrete structures.

Taboo 10

The flange plates and gaskets for pipeline connection have insufficient strength, and the connecting bolts are short or thin in diameter. Rubber gaskets are used for thermal pipelines, double-layer gaskets or beveled gaskets are used for cold water pipelines, and the flange gasket protrudes into the pipe.
Consequence: The connection of the flange plates is not tight, and even damaged, resulting in leakage. The protrusion of the flange gasket into the pipe will increase the water flow resistance.
Measure: The flange plates and gaskets used for pipelines must meet the requirements of the pipeline design working pressure. Rubber asbestos gaskets are suitable for the flange gaskets of heating and hot water supply pipelines; rubber gaskets are suitable for the flange gaskets of water supply and drainage pipelines. The flange gasket shall not protrude into the pipe, and its outer circle should be appropriate to the flange bolt holes. Beveled gaskets or several gaskets shall not be placed in the middle of the flange. The diameter of the bolts connecting the flange should be 2mm smaller than the flange hole diameter, and the length of the bolt rod protruding from the nut should be 1/2 of the nut thickness.
Taboo 11

Incorrect valve installation method. For example, the water (steam) flow direction of the stop valve or check valve is opposite to the mark, the valve stem is installed downward, the horizontal check valve is installed vertically, the handle of the gate valve or butterfly valve has no opening and closing space, and the valve stem of the concealed valve does not face the inspection door.
Consequence: The valve fails, and it is difficult to open, close and repair. The downward installation of the valve stem often causes water leakage.
Measure: Install strictly in accordance with the valve installation instructions. Leave sufficient valve stem extension opening height for the gate valve with exposed stem. Fully consider the handle rotation space for the butterfly valve. The valve stems of various valves cannot be lower than the horizontal position, let alone downward. For the concealed valve, not only an inspection door that meets the valve opening and closing needs should be set, but also the valve stem should face the inspection door.

Taboo 12

The specifications and models of the installed valves do not meet the design requirements. For example, the nominal pressure of the valve is less than the system test pressure; a gate valve is used when the diameter of the water supply branch pipe is less than or equal to 50mm; a stop valve is used for the main and riser pipes of hot water heating; a butterfly valve is used for the suction pipe of the fire pump.
Consequence: It affects the normal opening, closing, resistance regulation, pressure regulation and other functions of the valve. Even during the system operation, the valve is damaged and has to be repaired.
Measure: Be familiar with the application range of various valves and select the specifications and models of valves according to the design requirements. The nominal pressure of the valve should meet the requirements of the system test pressure. According to the construction specification requirements: a stop valve should be used when the diameter of the water supply branch pipe is less than or equal to 50mm; a gate valve should be used when the diameter is greater than 50mm. The control valves of the main and riser pipes of hot water heating should be gate valves, and the suction pipe of the fire pump should not be a butterfly valve.
Taboo 13

Necessary quality inspection is not carried out before valve installation according to regulations.
Consequence: During the system operation, the valve is not flexible in opening and closing, not tightly closed, and has water (steam) leakage, resulting in rework and repair, and even affecting the normal water supply (steam).
Measure: Before valve installation, a pressure resistance strength and tightness test should be carried out. The test should be carried out by sampling 10% of each batch (same brand, same specification, same model), and at least one. For the closed-circuit valves installed on the main pipe and playing a cutting-off role, a strength and tightness test should be carried out one by one. The test pressure of valve strength and tightness should meet the requirements of "Code for Acceptance of Construction Quality of Building Water Supply, Drainage and Heating Engineering" (GB 50242 - 2002).

Taboo 14

The main materials, equipment and products used in the construction lack the technical quality appraisal documents or product certificates that meet the current national or ministerial standards.
Consequence: The project quality is unqualified, there are potential accident risks, it cannot be delivered for use on schedule, and rework and repair are required; resulting in project delay, and increased labor and material inputs.
Measure: The main materials, equipment and products used in the water supply, drainage and heating and plumbing engineering should have technical quality appraisal documents or product certificates that meet the current national or ministerial standards; their product names, models, specifications, national quality standard codes, production dates, names and locations of manufacturers, and factory product inspection certificates or codes should be indicated.

Taboo 15

Valve installed upside down
Consequence: Valves such as stop valves, throttle valves, pressure reducing valves, and check valves have directionality. If installed upside down or reversed, the throttle valve will affect the service effect and service life; the pressure reducing valve will not work at all, and the check valve may even cause danger.
Measure: For general valves, there is a direction mark on the valve body; if not, the direction should be correctly identified according to the working principle of the valve. The valve cavity of the stop valve is asymmetrical left and right. The fluid should pass through the valve port from bottom to top, so that the fluid resistance is small (determined by the shape), the opening is labor-saving (due to the upward pressure of the medium), and after closing, the medium does not press the packing, which is convenient for maintenance. This is the reason why the stop valve cannot be installed reversely. The gate valve should not be installed upside down (that is, the handwheel is downward), otherwise the medium will remain in the valve cover space for a long time, which is easy to corrode the valve stem, and is also prohibited by some process requirements. At the same time, it is extremely inconvenient to replace the packing. The gate valve with exposed stem should not be installed underground, otherwise the exposed valve stem will be corroded due to humidity. When installing the lift check valve, ensure that its valve disc is vertical for flexible lifting. When installing the swing check valve, ensure that its pin shaft is horizontal for flexible swinging. The pressure reducing valve should be installed upright on the horizontal pipeline and should not be inclined in any direction.

Taboo 16

Excessive force is used to open and close manual valves.
Consequence: At best, the valve is damaged; at worst, a safety accident is caused.
Measure: The handwheel or handle of a manual valve is designed according to ordinary human power, considering the strength of the sealing surface and the necessary closing force. Therefore, long levers or long wrenches cannot be used to operate. Some people are used to using wrenches and should pay strict attention not to use excessive and violent force, otherwise the sealing surface is easily damaged, or the handwheel and handle are broken. When opening and closing the valve, the force should be stable and not impact. The various components of some high-pressure valves that are opened and closed by impact have considered this impact force and are different from ordinary valves. For steam valves, they should be preheated and the condensed water should be drained before opening. When opening, it should be as slow as possible to avoid water hammer phenomenon. When the valve is fully opened, the handwheel should be reversed a little to make the threads tight to avoid loosening and damage. For the gate valve with exposed stem, remember the valve stem position when fully open and fully closed to avoid hitting the top dead center when fully open and to facilitate checking whether it is normal when fully closed. If the valve disc falls off or large debris is embedded between the valve core seals, the valve stem position when fully closed will change. When the pipeline is first used, there are more internal dirt. The valve can be slightly opened to use the high-speed flow of the medium to wash it away, and then gently closed (not quickly or violently closed to prevent the residual impurities from scratching the sealing surface), opened again, and repeated several times to wash away the dirt and then put it into normal work. For the normally open valve, there may be dirt sticking on the sealing surface. When closing, it should also be washed clean with the above method and then officially closed tightly. If the handwheel or handle is damaged or lost, it should be replaced immediately. Do not use a monkey wrench instead to avoid damaging the square of the valve stem, resulting in poor opening and closing and even accidents in production. For some media, after the valve is closed, it cools down, causing the valve parts to shrink. The operator should close it again at an appropriate time to leave no fine gap on the sealing surface. Otherwise, the medium flows at high speed through the fine gap, which is easy to erode the sealing surface. When operating, if it is found that the operation is too laborious, the cause should be analyzed. If the packing is too tight, it can be appropriately loosened. If the valve stem is skewed, the maintenance personnel should be notified to repair it. For some valves, when in the closed state, the closing part expands due to heat, resulting in difficulty in opening; if it must be opened at this time, the valve cover thread can be loosened by half a turn to one turn to eliminate the valve stem stress, and then the handwheel can be turned.

Taboo 17

Improper installation of valves in a high-temperature environment.
Consequence: A leakage accident is caused.
Measure: For high-temperature valves above 200°C, since they are at normal temperature during installation and the temperature rises after normal use, the bolts expand due to heat and the clearance increases, so they must be tightened again, which is called "hot tightening". The operator should pay attention to this work, otherwise leakage is likely to occur.

Taboo 18

Failure to drain in time in cold weather.
Measure: When the weather is cold and the water valve is closed for a long time, the accumulated water behind the valve should be drained. After the steam valve stops steaming, the condensed water should also be drained. If there is a plug at the bottom of the valve, it can be opened to drain water.
Taboo 19

The opening and closing force of non-metallic valves is too large.
Measure: Some non-metallic valves are hard and brittle, and some have low strength. When operating, the opening and closing force cannot be too large, especially not using brute force. Also pay attention to avoiding collisions.

Taboo 20

The packing of new valves is too tight.
Measure: When using a new valve, the packing should not be pressed too tightly, just to the extent that there is no leakage, to avoid excessive pressure on the valve stem, accelerated wear, and difficult opening and closing. The installation quality of the valve directly affects its use, so attention must be paid to the direction and position of the valve, valve installation work, valve protection facilities, bypass and instrumentation, and valve packing replacement.

Taboo 21

There is no operating space at the installation position.
Measure: The installation position of the valve must be convenient for operation; even if the installation is temporarily difficult, it should also be considered for the long-term work of the operator. Preferably, the valve handwheel is at the same height as the chest (generally 1.2 meters from the operating floor). In this way, it is more labor-saving to open and close the valve. The handwheel of the floor-standing valve should face upward and not be inclined to avoid awkward operation. For the valve against the wall or equipment, also leave room for the operator to stand. Avoid operating with the face upward, especially for acid, alkali, toxic media, etc., otherwise it is very unsafe.
Taboo 22

Hitting valves made of brittle materials.
Measure: Installation construction must be careful and avoid hitting valves made of brittle materials. Before installation, the valve should be inspected, the specifications and models should be checked, and whether there is damage should be identified, especially for the valve stem. Also turn it a few times to see if it is skewed, because the valve stem is most likely to be skewed during transportation. Also remove the debris in the valve. When hoisting the valve, the rope should not be tied to the handwheel or valve stem to avoid damaging these parts, but should be tied to the flange. The pipeline connected to the valve must be cleaned thoroughly. Compressed air can be used to blow away iron oxide chips, sediment, welding slag and other debris. These debris not only easily scratch the sealing surface of the valve, but also large particle debris (such as welding slag) can block small valves and make them ineffective. When installing a screwed valve, the sealing packing (linen thread with lead paint or polytetrafluoroethylene raw material tape) should be wrapped around the pipe thread and not put into the valve to avoid accumulation in the valve and affect the medium flow. When installing a flange valve, pay attention to tightening the bolts symmetrically and evenly. The valve flange and the pipe flange must be parallel and the clearance is reasonable to avoid excessive pressure on the valve and even cracking. Pay special attention to valves made of brittle materials and valves with low strength. For valves that need to be welded to the pipe, spot welding should be carried out first, then the closing part should be fully opened, and then welded firmly.
Taboo 23

No heat preservation and cold insulation measures are taken for valves.
Measure: Some valves also need external protection facilities, which are heat preservation and cold insulation. Sometimes a heating steam pipeline is added in the heat insulation layer. Which valves should be heat-insulated or cold-insulated depends on the production requirements. Generally speaking, if the temperature of the medium in the valve decreases too much, which will affect production efficiency or freeze the valve, heat preservation is required, and even heat tracing; if the valve is exposed, which is unfavorable for production or causes adverse phenomena such as frosting, cold insulation is required. Heat insulation materials include asbestos, slag wool, glass wool, perlite, diatomaceous earth, vermiculite, etc.; cold insulation materials include cork, perlite, foam, plastic, etc.

Taboo 24

The bypass of the steam trap is not installed.
Measure: Some valves, in addition to necessary protection facilities, also need a bypass and instrumentation. Installing a bypass facilitates the maintenance of the steam trap. Other valves also have bypasses installed. Whether to install a bypass depends on the condition, importance and production requirements of the valve.
cTaboo 25

The packing is not replaced regularly.
Measure: For the valves in stock, some packings are no longer effective, and some do not match the medium used, so the packing needs to be replaced. The valve faces thousands of different media. The packing box is always filled with ordinary packing, but when in use, the packing must match the medium. When replacing the packing, it should be pressed in one circle at a time. The joint of each circle is preferably 45 degrees, and the joints of the circles are staggered by 180 degrees. The height of the packing should consider the room for further tightening of the gland, and at the same time, the lower part of the gland should press the packing chamber to an appropriate depth, which is generally 10 - 20% of the total depth of the packing chamber. For valves with high requirements, the joint angle is 30 degrees. The joints between the circles are staggered by 120 degrees. In addition to the above packings, shaped packings such as rubber O-rings (natural rubber is resistant to weak alkalis below 60°C, nitrile rubber is resistant to oils below 80°C, fluorine rubber is resistant to various corrosive media below 150°C), three-piece stacked polytetrafluoroethylene rings (resistant to strong corrosive media below 200°C), and nylon bowl-shaped rings (resistant to ammonia and alkali below 120°C) can also be used according to specific circumstances. Wrapping a layer of polytetrafluoroethylene raw material tape outside the ordinary asbestos packing can improve the sealing effect and reduce the electrochemical corrosion of the valve stem. When tightening the packing, turn the valve stem at the same time to keep it uniform around and prevent it from being too tight. Tighten the gland evenly and not obliquely.

Valve as an important part of general machinery products, its market capacity is no less than pump products, according to the National Association of General Machinery Valve Branch statistics, the domestic market capacity of the valve in more than 60 billion yuan (excluding exports to foreign valve dosage); This fully demonstrates the great potential of the valve market. It is often said that "pump valve is one, there must be a pump valve," as two highly relevant products, its products, Prices, channels, etc., have a lot of similarities, but it can not be understood as a pump only related products or ancillary products, and in fact in addition to the pump valve, such as steel, petroleum, chemical, electricity, Food, aviation and other fields require a large number of valves in the pipeway, so rather than saying "there must be valves in a pump," it is more accurate to say "there must have valves in an pipeline." It is also very different from pumps in the marketing process in terms of product, channel and price, which can be summarized as follows:

At present, the number of valve enterprises in China ranks first in the world, and has been able to produce more than a dozen major categories of products. Such as gate valves, globe valves, ball valves, butterfly valves, safety valves, boiler check valves, throttle valves, plug valves, pressure reducing valves, diaphragm valves, steam traps, emergency shut-off valves, etc. However, there are still external leakage, internal leakage, poor appearance quality, short life, inflexible operation and unreliable valve electric devices and pneumatic devices, some products are only equivalent to the foreign level of the 1990s. This main reason may be with our country so far almost no colleges and universities have opened a valve professional, there is no basic systematic education has a lot to do; Usually in mechanical design or fluid machinery and other professional with a little knowledge of the valve. There is no professional product design learning, so it caused a relative shortage of designers in the valve industry, and procurement personnel in engineering projects also know little about the valve; Therefore, the design, manufacturing, procurement and other personnel in the valve industry are relying on self-learning to improve, so individuals have a certain deviation in their understanding of valve products. This has created a strange phenomenon that often produces inexplicable problems in the process of valve design, manufacturing and sales, which should be a process of slow progress from disorder to maturity in the entire valve industry, and the difference between valves and pumps in products is mainly reflected in the following aspects. (1) The product structure and working principle are simpler than the pump and do not involve the power system; General valves generally do not perform professional calculations and tests on flow, vapor corrosion and other data, and there is a large gap compared with foreign valve companies, and domestic valve product samples do not reflect the corresponding data, only staying on installation dimensions and materials, and there are still a lot of room for learning and improving. 2, the degree of product standardization is higher than the pump, China's valve standards are mainly national standards (GB), the Ministry of Machinery standard (JB), the Ministry of Chemical Industry standard (HG), etc., these standards mainly refer to the former Soviet Union and Germany's valve standards. The structure, size, material, testing and other aspects of the general-purpose valve have been standardized, so the interchangeability of the domestic valve is higher than that of the pump, and there are generally no major technical obstacles (except for a small number of patented technology products). 3, the product type is more than the pump and miscellaneous, China's existing about more than 2300 valve types, about 30000 kinds of specifications, in such a wide variety of valve types, Cut off the type of valve connected to the use of the entire 80%, such as gate valves, globe valves, ball valves, butterfly valves are connected to cut off the type of valve, other non-return, regulation, steam water separation, reversing and other uses of the type of valve accounted for only 20% of the total amount; Among them, many types of valves connected to the cut-off class can be replaced by each other, mainly depending on the selection in engineering design; Such as in the municipal water supply pipeline on the original extensive use of long structure, bulky valve, to the present majority of the use of light weight, soft sealing butterfly valve transition. 4, before the valve factory must go through the relevant testing and debugging, product quality than pump products better grasp, so on-site guidance installation, debugging and other after-sales service is relatively small; Such as safety valve, mud relief valve, etc., involving take-off pressure, pressure reducing valve, such as the need for commissioning, generally in the factory before the manufacturers have been in accordance with the technical requirements of the contract to do a good job of commissioning, on-site installation only in accordance with the instructions connected to the pipeline can be used normally. 5, the manufacturers of external procurement more frequent; Due to the variety and variety of the valve itself, the valve company cannot produce all of its own, so when the manufacturer performs the contract, it is necessary to integrate the advantages of other suppliers to organize the supply. Then rely on the enterprise's own management process to good quality, which is also the inevitable industry segmentation and market competition; Such as my company's electric valve, pneumatically operated valve, hydraulic valve, such as automatic valve electric, pneumatic, hydraulic actuators are also supporting the outside, but because over the years I control system manufacturing experience, the assembly of the automatic valve and control system debugging more obvious advantages. 6, key industries, key enterprises, key parts of the valve are required once a year maintenance period, such as power, petroleum, chemical and other industries in the application of most of the valves, Every year, valves that have reached the service life are serviced and replaced, and the inspection of valves is generally directly replaced in a set of new valves, completely different from the service and replacement of spare parts for pump products, which is an important reason for the huge market capacity of valves and its growth year by year.

Second, the sales channels of China's existing valve of various sizes about more than 5000 enterprises, of which the annual output value of more than 10 million yuan has more than 500, the output value of more than 100 million yuan just a few dozen, in addition to the valve product variety, demand and scattered positioning of the various industries other than the different reasons，A very important reason is that the valve company's own sales channels, and imports or joint venture valve enterprises in their own channel construction, maintenance and control there is a large gap, the domestic valve enterprises sales channels and the following forms. 1, almost no own sales channels, this kind of main low-level, small-scale, family-type enterprises, long-term survival by OEM processing; The starting point of the enterprise is low, the management level and technical force are very weak, the equipment is simple, and most of the products are imitation production, mainly producing low-pressure valves for water supply and drainage. 2, the vast majority of domestic valve companies imitate the sales model of fast-moving consumer goods, using a relatively extensive agency system, relying on intermediate agents to achieve enterprise sales activities to end users; This model makes the risk of valve enterprises smaller, because the general valve company's settlement method for agent intermediaries is payment to delivery. Valve companies sacrifice their own sales gross profit and brand added value to achieve rapid return of funds, to avoid the risk of return, while most of the pre-sale, sale, after-sales costs transferred to the head of the middleman; However, the disadvantage of this model is that the valve enterprise itself is difficult to manage and control the agent. In order to maximize profits, middlemen usually find cheaper small factories to brand. Shoddy, serious damage to the brand of the valve company itself, while the agent middleman loyalty to the valve company is very low, and even the agent at the same time 35 valve brand, in the project bidding Wai standard illegal phenomenon occurs. 3, a small number of domestic valves have set up their own sales branches, directly facing end users; This part of the valve enterprises mainly in a specific industry or a specific region of the private valve enterprises, but also only belongs to the initial stage, its management of direct selling companies is more extensive; Unlike most of the pump manufacturers, which have their own controllable direct sales network, there is still a big gap in project information collection, large project tracking, bid negotiation, business personnel training, after-sales tracking and return visit, and communication with design institutes. Three product price valve target customers and pumps are consistent, are used in all kinds of civil construction, municipal, industrial and mining projects, but in the market price is still relatively chaotic. (1) In particular, the market price of civil construction and municipal project valves is because such project valves generally use low-pressure cast iron valves with low value and technical content, and the manufacturers producing such valves mostly use agents and middlemen to sell them, resulting in low-quality and low-price competition among each other in the bids. It is easy to mislead purchasers to win tenders at low prices, even sales below the cost price of the product, and valve manufacturers or middlemen must cut corners in the process and materials in order not to lose money, and the valves produced are subject to quality hazards, and it is the users themselves who will eventually suffer. Such as the so-called "hometown of Chinese valves" in Wenzhou Oubei town part of the valve prices to attract intermediaries OEM processing orders, the valve products based on its weight, material, wall thickness is divided into standard, heavy, light and many other levels to meet the demands of intermediaries to maximize profits. 2, industrial and mining project valve its product itself in the material, weight, control system and other aspects have certain technical requirements, Therefore, the market price of valves for such projects is relatively reasonable, and many professional valve manufacturers for industrial and mining industries use the principle of value engineering, strengthen the main functions of products, remove redundant functions, optimize system configuration, and develop a number of patented products; At the same time, strengthen the internal management of enterprises, work hard on cost accounting, and have a better price positioning in the market of their own superior products and industries. 3, environmental protection, nuclear power and other emerging industries with the valve is a breakthrough, increase technical research and development input to design new industry with the valve can be in the price chaos in the general valve market another way; Such as China's next five years will invest about 900 billion to the nuclear power industry, and in accordance with the relevant national provisions of which 70% of the equipment must be localized, in which the amount of valve equipment is bound to be huge, is another new domestic valve profit growth point. To sum up, although the market potential of the valve industry is huge, but the valve industry is still clearly in an industry reshuffle stage, at the same time, such as environmental protection, nuclear power valves and other new industries to the domestic valve enterprises put forward more opportunities and challenges. I believe that there will be a long-term vision of the domestic valve enterprises, in this reshuffle process rely on technological innovation, product quality management process reengineering, integration of social advantages of resources, building their own strong sales network to achieve brand status in the industry.

1、 Drive mode

Manual ball valve:

The opening and closing actions of the ball valve are achieved by manually rotating the valve stem. During operation, the operator directly acts on the handwheel or handle, manually rotates the valve stem, and then drives the ball core to rotate, achieving the purpose of controlling fluid flow.

Pneumatic ball valve:

Using compressed air as the power source, the opening and closing of the ball valve are driven by pneumatic actuators. Pneumatic actuators receive pressure signals from the control system, convert pressure energy into mechanical energy, drive the valve stem and ball core to rotate, and achieve fluid control.

2、 Working principle

Manual ball valve: When the valve stem is manually rotated to align the through-hole of the ball core with the pipeline axis, the valve is fully open and fluid can pass smoothly; When the ball core rotates 90 degrees and the through-hole of the ball core is perpendicular to the pipeline axis, the valve is completely closed, preventing fluid from passing through.

Pneumatic ball valve: After the control system sends the valve opening signal, compressed air enters the air inlet of the pneumatic actuator, pushing the piston or diaphragm and other actuating components to move, driving the valve stem and ball core to rotate 90 degrees, achieving valve opening; When receiving the valve closing signal, the actuator exhausts, and under the action of the spring or other reset device, the valve stem and ball core rotate in the opposite direction by 90 degrees, and the valve closes.

3、 Performance characteristics

Manual ball valve operation is simple and flexible: the structure is relatively simple, and manual operation is convenient and fast. Operators can easily control the opening of the valve according to actual needs. Low cost: Due to the absence of complex driving devices such as pneumatic actuators, the manufacturing and procurement costs of manual ball valves are relatively low. High reliability: Without complex pneumatic or electric control systems, it reduces the risk of failure caused by electrical faults or gas source issues, and has high reliability in some simple working conditions.

4、 Pneumatic ball valve quick response:

Pneumatic actuators have fast response capabilities and can complete the opening and closing of valves in a short period of time, making them suitable for situations that require high switching speeds. High degree of automation: It can be integrated with various automation control systems to achieve remote control and automated operations, facilitating centralized management and monitoring. High output torque: Pneumatic actuators can provide a large output torque, suitable for large-diameter ball valves or ball valves used in high-pressure, high viscosity media and other working conditions, and can easily overcome the resistance when the valve is opened and closed.

5、 Applicable scenarios for manual ball valves and low-pressure small-diameter pipelines:

In some low-pressure, small-diameter pipeline systems, such as household water supply and drainage pipelines, small air conditioning system pipelines, etc., manual ball valves can meet simple on-off control requirements, with low cost and easy operation.

Occasions of infrequent operation:

For some occasions that do not require frequent valve operation, such as certain backup pipelines or occasionally used branch pipelines, the simple and reliable characteristics of manual ball valves make them a suitable choice.
Areas with convenient on-site manual control: In areas where operators can easily access valves for on-site manual control, such as local pipeline systems in small factories, equipment pipelines in laboratories, etc., manual ball valves can quickly achieve on/off operations. Automated production process of pneumatic ball valves: Pneumatic ball valves are widely used in the automatic control of fluid conveying pipelines on automated production lines in industries such as petroleum, chemical, pharmaceutical, and food. They can seamlessly integrate with control systems such as PLC and DCS to achieve automation and intelligence in the production process.
In situations where fast switching is highly required, such as emergency shutdown systems, fire protection systems, gas supply systems, etc., pneumatic ball valves can respond quickly to ensure the safe and reliable operation of the system. Adverse environmental conditions: In some harsh environmental conditions such as high temperature, high pressure, flammability, explosiveness, toxicity, etc., pneumatic ball valves can be remotely controlled to avoid direct contact with hazardous environments by operators and improve operational safety.

1、 Working principle

The working principle of a pressure reducing valve is mainly achieved by adjusting the opening of the valve and utilizing the pressure loss generated by the fluid passing through the throttle to achieve the pressure reducing function. It generally includes an adjustable valve core structure. When fluid flows in from the inlet, passes through the throttling area between the valve core and the valve seat, the pressure decreases, and then flows out from the outlet. Under normal circumstances, the inlet pressure acts on one side of the valve core, and the outlet pressure acts on the other side of the valve core through the control channel. The pressure difference between the two is balanced with the spring force, thereby determining the position of the valve core and the opening of the valve.

2、 Analysis of the state when the import is blocked

1) Spring type pressure reducing valve

Valve core position:

When the inlet is blocked, no fluid enters the pressure reducing valve, and the valve core will be in a closed state under the action of spring force. Because there is no import pressure to counteract the spring force, the spring will push the valve core towards the valve seat, causing the valve to close tightly. For example, in a simple water spring pressure reducing valve, after the inlet pressure disappears, the spring will cause the valve core to tightly adhere to the valve seat, preventing any reverse flow or accidental opening.

Changes in export pressure:

Due to the lack of new fluid replenishment, the pressure on the outlet side will gradually decrease with the use or leakage of downstream equipment. If the downstream is a closed system and there is no leakage, the outlet pressure will remain basically unchanged, but once there is any trace leakage or usage, the pressure will decrease until it reaches equilibrium with the external environmental pressure or the system is completely depressurized.

3. The difference between constant pressure reducing valve and proportional pressure reducing valve

Fixed pressure reducing valve:
Whether it is a spring-loaded constant pressure reducing valve or a pilot operated constant pressure reducing valve, the main state when the inlet is blocked is that the valve core is closed and the outlet pressure drops. The purpose of a constant pressure reducing valve is to lower the inlet pressure to a fixed output value. When there is no pressure input from the inlet, it cannot achieve the pressure reducing function and only remains closed to prevent backflow and other situations.

Proportional pressure reducing valve:

The output pressure and inlet pressure of the proportional pressure reducing valve are adjusted according to a certain proportional relationship. When the inlet is blocked, like a constant pressure reducing valve, the valve core closes and the output pressure decreases with downstream conditions. However, its internal structure may be slightly more complex due to the design characteristics of proportional adjustment, and the adjustment process may be slightly more complicated when the inlet pressure is restored, requiring the re establishment of control parameters such as valve core position corresponding to proportional relationships.

Terrazzo floors combine durability, style, and usefulness, which make it a great option for sports facilities. These resilient floors are ideal for gyms, locker rooms, and indoor courts where heavy equipment and frequent foot activity necessitate a sturdy surface. Their non-porous finish makes cleaning simple, lowers the possibility of bacterial accumulation, and promotes a healthier atmosphere for both employees and athletes.

One of the standout features of terrazzo floors is their ability to support creative and custom designs. From team logos to facility branding, terrazzo floors can be tailored to fit any aesthetic vision. Achieving such precision during the installation process often requires diamond grinding tools, which are instrumental in creating a perfectly smooth surface that enhances the design’s clarity and vibrancy.

Another major advantage of terrazzo floors is their long-term cost efficiency. These floors are incredibly tough, resisting chips, cracks, and stains over time. When signs of wear eventually appear, professionals use metal bond diamond grinding tools to repair and restore the surface. This process ensures the floor maintains its structural integrity and sleek appearance, even after years of use in demanding environments.

Sustainability is another benefit of terrazzo flooring. Made from a combination of natural aggregates and recycled materials, terrazzo is an eco-friendly choice for facilities looking to minimize their environmental footprint. To further enhance its finish, experts often turn to diamond polishing pads, which provide a high-gloss sheen that improves the floor’s durability and aesthetics while reducing maintenance needs.

Terrazzo floors offer unparalleled durability and aesthetics for sports facilities, and maintaining their high performance and visual appeal requires the right tools. TransGrind is a professional manufacturer and supplier of premium diamond grinding tools, designed for superior performance, durability, and precision. Explore our full range of products at www.transgrindtools.com to ensure optimal results for your flooring needs.

Terrazzo flooring has emerged as a popular option for retail environments, combining durability, style, and adaptability. This classic material not only enhances visual appeal but also offers practical advantages suited to the high demands of retail spaces. Its ability to endure heavy foot traffic while complementing contemporary interior designs makes terrazzo flooring a standout choice for stores aiming to leave a lasting impression.

Retail environments face continuous wear from foot traffic, shopping carts, and heavy displays. The structure of terrazzo—composed of marble, quartz, or glass chips set in a cement or epoxy base—ensure it can handle these stresses without significant deterioration. Maintaining its polished finish typically involves diamond grinding tools, which help restore its shine and smoothness, making it a cost-effective investment.

In terms of aesthetics, terrazzo floor provides unparalleled design options. Retailers can select from a vast array of colors, patterns, and finishes to reflect their brand identity. The polished surface offers a luxurious look, while its non-porous nature makes it easy to clean and maintain. Regular grinding and polishing with TransGrind diamond grinding tooling can keep the floors looking pristine, enhancing the overall shopping experience.

Sustainability is another factor driving the popularity of terrazzo in retail design. Many terrazzo installations use recycled materials, supporting eco-friendly building practices. Furthermore, its longevity reduces the need for frequent replacements, thereby minimizing waste. For businesses aiming to maintain and refurbish their terrazzo floors, tools like metal bond diamond grinding tools offer an effective way to smooth out uneven surfaces and prepare the floor for resealing or repolishing.

The advantages of terrazzo flooring making it an exceptional choice for retail spaces. Its durability, visual appeal, and sustainability align seamlessly with the requirements of modern retailers. For businesses looking to install of maintain terrazzo floors, using the appropriate equipment, such as diamond grinding tools, is crucial for achieving the best results. With its expertise in producing high-quality tools, TransGrind is a dependable partner for keeping your terrazzo floors in excellent condition.

Transformer core plays a crucial role in the efficient and reliable transmission of electrical power. As a key component, it provides a low reluctance path for the magnetic flux generated by the primary winding to be transferred to the secondary winding. Among various materials used for transformer cores, oriented silicon steel, also known as CRGO (Cold-Rolled Grain-Oriented) silicon steel or electrical steel, stands out for its exceptional magnetic properties and widespread application in different power ratings of transformers.

CRGO Silicon Steel: A Superior Core Material:

CRGO silicon steel is specifically engineered to exhibit grain orientation, enabling it to maximize its magnetic properties when subjected to an alternating magnetic field. The manufacturing process involves a controlled cold rolling technique that aligns the crystal grains within the steel in a specific direction. This grain orientation reduces the occurrence of magnetic domains and minimizes hysteresis losses and eddy current losses, making CRGO silicon steel the preferred choice for transformer cores.

Applications in Different Power Ratings:

1. Low-Power Transformers:
   In low-power transformers, such as those used in residential and small-scale commercial applications, CRGO silicon steel is utilized to enhance energy efficiency. The material's low core losses and high magnetic permeability contribute to reduced power wastage and improved voltage regulation, ensuring optimum performance in household appliances, lighting systems, and electronic devices.

2. Medium-Power Transformers:
   Medium-power transformers, commonly employed in industrial settings and power distribution networks, require reliable and efficient core materials. CRGO silicon steel offers excellent magnetic properties at intermediate power ratings, enabling enhanced energy transmission and minimal power losses. These transformers find application in areas such as manufacturing facilities, commercial buildings, and utility substations.

3. High-Power Transformers:
   For high-power transformers, such as those used in large-scale power generation and transmission systems, CRGO silicon steel provides superior performance. With its advanced grain orientation and optimized magnetic characteristics, it minimizes core losses and enhances efficiency, ensuring reliable power transmission over long distances. These high-power transformers are crucial components of electrical grids, enabling the efficient distribution of electricity to cities, industries, and infrastructure projects.

 

 

The selection of the core material plays a vital role in the performance and efficiency of transformers. CRGO silicon steel, also known as oriented silicon steel or electrical steel, stands out as an ideal choice for transformer cores across different power ratings. Its unique grain orientation and magnetic properties significantly reduce energy losses, ensuring optimal power transmission. Whether in low-power, medium-power, or high-power transformers, CRGO silicon steel demonstrates its superiority in enhancing efficiency and reliability in the transmission and distribution of electrical energy.

In modern electrical control cabinets, the effective management of electrical connections is crucial for maintaining a reliable and safe system. Barrier terminal blocks play a vital role in providing secure and organized electrical connections, ensuring proper signal transmission and control. In this article, we will explore the significance of barrier terminal blocks and their applications in electrical control cabinets.

 

Barrier Terminal Blocks: The Foundation of Secure Connections

Barrier terminal blocks are specifically designed to provide a secure connection between wires and other electrical components. With their robust construction and insulation materials, these terminal blocks offer excellent electrical isolation and protection against short circuits. The 5.08 mm barrier terminal block, barrier terminal block connector, and pcb terminal block connector are popular choices for various wiring applications.

 

Ensuring Reliable Signal Transmission with PCB Terminal Blocks

For precise signal control in electrical control cabinets, the selection of the right terminal block connector is paramount. PCB terminal blocks, such as the pcb terminal connector and terminal block connector pcb, are designed to facilitate efficient signal transmission between printed circuit boards and other components. Their compact size and reliable connection capabilities make them ideal for space-constrained applications.

 

Simplifying Wiring with Terminal Block Connectors

Terminal block connectors provide a convenient and efficient solution for connecting and disconnecting wires in electrical control cabinets. The barrier terminal block connector, along with the terminal block electrical connector, offers a user-friendly interface, allowing for easy installation and maintenance. These connectors reduce wiring complexity and enhance flexibility during system modifications.

 

Reliable Performance in Harsh Environments

Electrical control cabinets often operate in challenging conditions, including high temperatures, vibrations, and humidity. Barrier terminal blocks, like the barrier terminal and terminal block connector pcb, are built to withstand such harsh environments. Their rugged design and superior insulation properties ensure stable performance and minimize the risk of electrical failures.

 

HONG YI-HOMNECKS: Your Trusted Barrier Terminal Block Manufacturer

When it comes to barrier terminal blocks, HONG YI-HOMNECKS is a leading manufacturer renowned for its quality and reliability. With a wide range of products, including the 5.08 mm barrier terminal block and terminal block electrical connector, HONG YI-HOMNECKS delivers innovative solutions to meet diverse customer needs.

Service Excellence: Partnering with HONG YI-HOMNECKS

Apart from their exceptional products, HONG YI-HOMNECKS is committed to providing outstanding customer service. Their expertise in barrier terminal blocks and personalized approach to customer support make them the go-to supplier for electrical control cabinet applications. With HONG YI-HOMNECKS, you can expect reliable products and unparalleled service.

 

Barrier terminal blocks play a crucial role in enabling secure and efficient electrical connections in control cabinets. The 5.08 mm barrier terminal block, barrier terminal block connector, and pcb terminal block connector are examples of versatile solutions that ensure reliable signal transmission. As a trusted manufacturer, HONG YI-HOMNECKS offers top-quality barrier terminal blocks and exemplary customer service. Whether you require barrier terminals or assistance in choosing the right solution for your application, HONG YI-HOMNECKS is here to fulfill your requirements and exceed your expectations