Qingdao Huakun Engineering

Recently, we faced some client to ask for the carbon brush. Based on our experience, we would like to share with whom need help on choosing carbon brush for Generator.

Client: " if we did not have the original drawing or brand, is that possible you supply?"

answer: " Yes, if you can supply the material and dimension requirement, we can supply."

Client: " How many different materials from China Generator manufacture?"

Answer: " There are different kinds of materials, such as D104, D172, S27, LFC554 and NCC634. It is depend on the

Generator technical specifications."

Client: " How about your dimension supply ?"

Answer: " we normally supply the dimensions such as 12.5*12.5*25, 12.5*10*32, 32*25*60, 32*20*40, 40*32*80, the unit is mm. "

Client: "Can you give me more instructions for that? "

Answer: " Sure. For Grounding Type Generator Carbon Brush normally used as D104 (12.5*12.5*25mm), D172 (12.5*10*32mm), D172 (32*20*40mm). But excitation model generator carbon brush normally used as D172 (32*25*60mm), N34 (2*(16*25*40mm)), S27 (32*25*60mm), LFC554 (40*32*80mm), NCC634 (40*32*80mm)."

Finally, we would like to share with you, if you want to replace the previous carbon brush of generator, please check and confirm the material and detail dimensions as following example. We can supply the completely support to you for that.

Green energy to love life

Joyous Garden is the only childcare institution for children aged 0-6 in Qingdao's Badaguan Scenic Spot. When I first met there, I was deeply attracted by the solar lights on the door and wall.

New energy has always been the direction that countries around the world are striving to pursue, and everyone is working hard to make our earth more suitable for long-term human habitation. In Qingdao, as a small coastal city, seeing such a kindergarten institution, solar lights have already been used in the courtyard and around the courtyard, which made me deeply interested in the educational philosophy of this kindergarten.
Through understanding, the master Seven is a music teacher who has always been concerned about early childhood education. She thinks that what we can bring to children is to see the world and feel the world with love, so that they will know more about life. Joyous chose solar lights to let these children pay attention to the fact that in addition to using electric lights, we can also choose more environmentally friendly and green energy, which can also achieve the effect of lighting. The teacher will also take the children to observe the structure of the solar lights in the yard, allowing them to discover the places that are different from the lights they usually use.

The solar lights in the yard have a waterproof rating of IP65, which is very friendly to the humid and rainy environment in Qingdao. At the same time, the color temperature selection of 3000-6500K can better adjust for different locations, so that the whole environment is brighter and warm. As a solar light, the issue of charging and power storage that we may be most worried about has also been well verified here. The charging time is 3-5 hours, and the power storage battery is more than 8000mAh, which can fully meet our daily use.
As we also love life, we are also working hard to develop the business of solar lighting. Through the visit and inspection of the factory production, we have selected a series of beautiful and high-quality lamp types, hoping to share with more users.

In June, one client purchased the collection ring of a 7MW generator and wanted to replace it. Can he replace it himself? The reason user think this way is that we supplied product with replacement solutions. After receiving the email from the user, I responded quickly, please arrange professional technicians to replace the collector ring. This work is not as simple as disassembling and assembling according to the solution.

The first things that need to be prepared in advance are:

1. The steam turbine has been opened and the rotor of the steam turbine has been hoisted away;

2. The generator rotor has been pulled out safely;

3. Place the generator rotor on the roller bracket so that the rotor can rotate;
After the above conditions are met, our professional technicians will perform the following work:

1. Use a professional wrench to remove the large lock nut at the end of the coupling. The estimated finish time is 1 day;

2. With the cooperation of two professional technicians, the coupling and the collector rings at both ends are disassembled through the heating process, and the estimated finish time is 1 day;

3. On-site replacement of new collector rings, with adjustment modules, and re-installation of couplings, the estimated finish time is 1 day;

4. According to the guidance of the technician, put the generator rotor back, and the technician will correct the coupling. The estimated working time is 2-3 days;

5. With the cooperation of on-site operators, the steam turbine has the conditions for running, and the generator technicians adjust the collection ring on site, and the estimated working time is 1-2 days;

Therefore, even if there are personnel with experience in operation and maintenance on site, referring to the replacement solution, without the professional technicians of the generator manufacturer, the replacement of the collection ring cannot be completed alone. In particular, the step of calibrating the coupling is very critical. It must be operated or helped by the professional engineers of the manufacturer to meet the standard requirements.

Professional people do professional things---- from Manufacture HT

With the development of the economy, more and more factories in China have gradually developed their own foreign trade companies, and they all want to do foreign trade directly through their own companies. However, in the end, the factory operation very prosperous, and instead of worrying about the capital problem, whom are concentrated on the technology improvement and quality control of the manufacturing enterprises. In the words of HT GM, "professional people should do professional things well. We are a manufacturing enterprise, starting from our President Director, the work that we prefer are how to improve our professional technology and bring that into production. The foreign trading is not our business. ".
As a professional manufacturer of components for biggest boiler manufacturers in China, HT can draw, process and produce the boiler components itself, except for the steam drum, and has a high quality inspection ability. However, HT has never been distracted to engage in foreign trade by himself. From the top management of the company to the office operators, the unanimous view is that as a manufacturing enterprise, quality is more important, how to make the best equipment and components, and improve the Defects of equipment, improving the efficiency of the overall operation of the equipment, and controlling every completed component are the things they should pay most attention.
Following such a company's business philosophy, HT has gradually learned and researched from a factory starting at 1990s to the present, and until now it has 4 factories with ASME certification and production license, specializing in the production of boiler air preheater, superheater, economizer, etc. It is precisely from the spirit of this technology research that HT has many successful cases of boiler transformation both at domestic and abroad, which have been well received by users.
We are very lucky to have such partner. Through technical communication with them, our professional level has also been greatly improved. We believe that in the future, through our mutual efforts, we will be able to bring better benefits to our customers. solutions and products.

Workshop Day

As a professional mechanical equipment and mechanical parts trading company, in order to better communicate with customers who has inquiry in a simple, clear and accurate manner, we have always kept constant communication with the factory, visited the factory workshop at any time to learn, and discussed with the workshop director about mechanical equipment. Technical features and requirements and progress of production.

This week we went to a manufacturer specializing in the production of boiler parts. There are three factories in the province and a large factory outside the province. The manufacturer mainly produces economizers, superheaters, air preheaters and anti-wear covers etc.

The product division of the factory is very clear, the processing equipment, production line and inspection workshop are all reasonably arranged, the division of labor work is very timely, and it is fully guaranteed that each process is completed fulfill the standard and qualified.

Economizers are divided into ordinary tube type, finned spiral tube type, and H fin type, all of which are being processed and assembled. The workshop director shared the most basic knowledge: the finned spiral tube type can be used in various furnace types, and the finned H type is currently mainly used in circulating fluidized beds and waste heat boilers, both of which have high thermal conductivity. At the same time, the ability to resist fly ash wear is also improved. In addition, these two types of economizers greatly reduce the use of space, freeing up a favorable layout space for customers to sell out of stock desulfurization devices, and also allowing customers to save a certain amount of cost, no matter from the number of pipes purchased or the service life.

Air preheater is currently divided into ordinary tube type, lined with enamel, outer lined with enamel, and inner and outer lined with enamel. As the first leading manufacture in China to propose enamel liner technology and designate Enamel lined GB standards, it has provided technical guidance and training opportunities to more than a dozen enamel liner factories, driving the improvement of the entire air preheater product, with a service life from The previous 3-5 years were extended to 5-8 years.
For extra-large air preheaters, the manufacture does not produce the whole set, but the main components of rotary air preheaters are produced for boilers above 600T, such as element heat exchangers, insert plate, etc. The production quality fully conforms to the three domestic biggest boiler manufacture technical requirement, meanwhile they keep the cost very advantageous.

Through the patient explanation of the workshop director, our team's understanding of the important parts of the boiler has been greatly improved technically. I believe that through this study, we can respond faster and more accurately to our customers who has any inquiry. We can help customers find better solutions by our engineering-economy growing support.

How important of Material Certificate?

Yesterday, I have received one information from some one I did not know. He asked me that their operation met melting problems on their long screw pin. He want us to suggest some material who can fulfill the resistance temperature ＞500℃.

That is not first time to happen. Each year, we will receive several times from different small power plant operator questions like this. Most times, the problem or the question is happened due to the material.

Material Certificate is one of the important document that the user asked. But no body can confirm that the material certificate is used on this order for this good, and if the user did not do inspection.

Take an example,

We have supplied many times Grate Bars for stoker boiler in Kalimantan. There are several small power plants there. Only one of the power plant will do inspection after the material arrival at site to check whether it fulfill the specification compared to the material certificate.

Now, the question is if no condition to do inspection by the user, how the user know whether the material is qualified or not. One basic method is weight comparation. If the user check the original drawing from manufacture, he can find the single weight. Compared to same material, the weight will be same more or less. If the material changed, better the user can calculate by himself or by manufacture, how about the single weight. It is one easy and fast way to check.

The material certificate should be issued by the actual manufacture, the fabricator or the factory. It will not be issued by one trading company. The raw material certificate and mill certificate should be from the material manufacture, not the product manufacture.

If as user, you can know the difference clear, I think everything will go well.

Stages Trash Firing Stoker #

Technical Characteristic:
1. Reverse acting stoker + layer adjusting + push forward stoker
2. Reverse acting grate angle 25°，16 stages layer, length 7500mm
3. Push forward grate horizontal layout, 6 stages layer, length 2400mm.
4. Layer adjusting height range 400~800mm
5. Large capacity per unit area, bearing mechanical load reaching 330kg/㎡
6. Single grate width 1650~2550mm, to be compared with dealing capacity of 100~175ton per day trash, capacity can be added by parallel connection;
7. Ash leakage less than 1%, which can be considered by air pneumatic system;
8. Modular design, whole set from factory, easy for er****on work;
9. Enough maintenance space for driven oil cylinder;
10. Round steel design grate bar, easy to be replaced;
11. Small foot layer, compared to large capacity processing per unit;
12. Three separate air chamber designed, which adjusted by central control system;

detail to: https://www.qdpower-engineering.com/Trash-Firing-Stoker-pd49133010.html

Grate Boiler Modification or Transformation

Boiler modification is the concern of our customers in Indonesia in recent years, and each user has different situations and different requirements. Some users just want to improve the efficiency of the long period operation of boiler and limited by the cost budget; while some users have to make the boiler modification due to the requirements of the policy or the change of fuel.

An Indonesian customer in Year 2020, we call it BW, used a 50 t/h coal-wood mixed combustion inverted chain grate boiler from a domestic boiler manufacture in 2007. BW wants to reduce operating costs by changing the high combustion value fuel to a mixture of low calorific value coal and waste wood. BW needs to reform the boiler for this purpose, and the load of the reformed boiler can meet the previous demand.

Here is the previous boiler parameters:

1. Boiler rated evaporation: 50 t/h

2. Boiler saturated steam pressure: 3.82 MPa

3. Boiler superheated steam temperature: 450 ℃

4. Boiler feed water temperature: 150 ℃

5. Design cooling air temperature: 30 ℃

6. Boiler efficiency: 81 %

7. Boiler exhausting flue gas temperature: 180 ℃

8. Previous design fuel: coal with 5252Kcal/kg : waste wood = 8:2

The target after modification will be:

1. Boiler rated evaporation: 40~50 t/h

2. Boiler saturated steam pressure: 3.82 MPa

3. Boiler superheated steam temperature: 450 ℃

4. Boiler feed water temperature: 150 ℃

5. Design cooling air temperature: 30 ℃

6. Boiler efficiency: 81 %

7. Boiler exhausting flue gas temperature: 145 ℃

8. Previous design fuel: coal with 5252Kcal/kg : waste wood = 8:2

Coal analysis:

Q netar 3000 ~4000 KCAL/kg

Waste wood combustion value：2600KCAL/kg

Waste wood crushed to less than dimension 40X40X5mm

How about the modification layout?

Each heating surface of the boiler can meet the operation requirements, so only the furnace is modified to ensure that the boiler can reach the rated evaporation and improve the thermal efficiency of the boiler when the calorific value of the fuel is low.

We change the coordination of the front and rear arches to make the flow rate of the flue gas at the roar more reasonable, increase the heating area of the furnace, add a secondary membrane water wall to the front wall, increase the heat absorption of the furnace, reduce the outlet temperature of the furnace, and protect the superheater.

In order to improve the combustion conditions, reduce coal consumption, increase the average temperature of the furnace, we increase the rear arch tube and the rear arch secondary air.

In order to improve the combustion degree of volatile matter in waste wood, we choose to change the structure of the secondary air nozzle on the front wall to increase the outlet flow rate, so that the secondary air has good rigidity and penetrating power.

Will the structure change??

Steam drum: adding 4 more holes in the drum for the new membrane water wall, the up and down tubes with specification φ89x5, others no change.

Water cooling system: The original design has no rear arch, this arrangement is not conducive to the timely combustion of low calorific value fuel, for this reason, it is necessary to transform the lower part of the rear wall to form a rear arch, and at the same time, a bend structure is adopted for the pipe part to arrange the secondary air, and the front arch is connected. It has good coordination, enhances the mixing and heat carrying capacity of high temperature flue gas, and avoids coking caused by local high temperature.

Superheater and temperature reduction system: no structure change but adding wear cover for the superheater.

Economizer: no structure change but adding wear cover.

Air preheater: no structure change, but user consider to change the enamel lined air preheater.

Combustion system: change the air nozzle to level structure;

Furnace wall: no change.

Boiler piping layout: adding drainage pipe for front water wall, others no change.

Secondary air draft: Change the position of the secondary air on the rear wall and the structure of the nozzle, to introduce the high-temperature flue gas and a large number of high-temperature hot particles into the rear of the furnace, which can ensure that the low-calorific value fuel absorbs heat and ignites in time, improves the combustion efficiency, and reduces the the incomplete combustion loss of the gas and the carbon content of the fly ash are beneficial to reduce the blackness and dust concentration of the flue gas.

Soot blower device: no change.

Why do steam turbine Bearing need to be replaced?
First of all, we need to communicate with the user whether the steam turbine has been cut off oil, resulting in serious bearing wear. If it is, then the Journal Bearing must be worn and damaged, and the concentricity of the entire rotor has also changed. As the maintenance personnel, we will consider whether the front and rear steam seals are worn under such circumstances, and whether the amount of wear is large? If there are no these problems, the maintenance personnel just replace the new Journal Bearing, and at the same time have to readjust the concentricity of the rotor. The maintenance personnel replace the bearing bushes individually, and then adjust the concentricity of the rotor, which takes about 2 weeks.
Here, we usually remind users according to the experience of operation and maintenance. Generally, the normal operation of the unit will wear out the bearing bushes after the oil is cut off and stop, and the user will replace the new bearing bushes. According to normal procedures, in this case, the cylinder needs to be opened and overhauled. If it is running normally and the amount of wear is small, it is difficult for the operator to detect it. Only when the turbine vibration and bearing temperature have increased, the operator can detect it. This situation shows that the wear problem of the bearing bush has been large, and the concentricity of the entire rotor has also moved down, so the steam seal will also be completely worn. Therefore, according to the different situations of users, we need to carefully communicate with users and analyze the actual situation on site, so that users can make correct judgments and have a clearer understanding of the materials and maintenance process required for their own steam turbine maintenance.

OVERALL RATINGS

Editor: Vera

Last Month, we received this overall rating from one of our customer in Indonesia, which giving us a lot of encouragement under this previous condition. Although, it is not 100 but higher than 80 very good as explained by the user. Thanks for the commendation from our user.

Since Covid-2019, it seems everything going on difficultly. We can not visit and same as our customer, they can not visit manufacture, factory, workshop….
Everything slowly moving and changing, we are still working as what we want, which is our life goal, trying to finish each inquiry / order same as you are the user.

The Covid condition seems to have increased our distance but has shortened our distance. We are not tired of running on the road, but have more time to sit down and communicate with customers: text, voice or phone video. I find this may be a better way to communicate, at least for me. Without the urge to face-to-face, video conversations allow us to better work towards getting a job done together.

Perhaps this is the precipitation brought to us by years and experience. No matter when and what environment, doing everything well with heart is the best communication and understanding between people.

We will take a more serious attitude, never fail to live up to the encouragement and recognition of all users, and better respond to every inquiry and serve every user well.

Know The Last Blade of Turbine Repalcement

1. What is the last stage blade?

The last stage blade of the steam turbine refers to the last stage blade of the steam process in the steam turbine, usually refers to the last stage blade of the low pressure cylinder of the steam turbine, and is also the longest stage of the turbine blades at all levels, and bears the largest centrifugal force load and the resulting stress.

Turbine blade2

2. Procurement of final blades

In recent years, our customers have always bought last stage blades. Some customers responded that one is that there are too many suppliers, and the quality is not clear. Sometimes the blades bought at a lower price are easy to break and prone to accidents. Another is that the domestic blade material standards are not clear, and the original factory random drawings are not properly kept, so there is no clear requirement for the supplier, which makes it impossible to verify the quality of the material.

According to our experience in purchasing equipment from a complete set of power plants for engineering and supplying spare parts for operating power plants, in fact, every regular manufacturer and supplier can provide the most direct proof of raw materials as long as he is really producing or manufacturing . If the basic raw material certificate is not available or cannot be provided, then the material cannot be guaranteed to be qualified first, and whether the supplier is familiar with the requirements of steam turbine drawings.

At the same time, if possible, the best way is to conduct an actual workshop inspection of unfamiliar factories or suppliers to check the real processing technology and production capacity, so as to communicate face-to-face and clarify the technical requirements, and at the same time. In the future procurement work, have a comparison and understanding of the current suppliers, and can better carry out the procurement work in the later stage.

3. Installation of the last stage blade

At present, customers who purchase final blades abroad will always face a problem, that is, the installation of final blades after order. So who will install the final blade?

The technical workers related to the installation and maintenance of steam turbines are roughly divided into: installers, operation and maintenance personnel, rotor maintenance personnel, and important component maintenance personnel (mainly manufacturers). So who exactly should perform the final blade maintenance? The answer is the maintenance technician of the rotor.

When it comes to rotor maintenance personnel, many customers are confused. Isn't the rotor part of the steam turbine? Is it possible to install by turbine erector, so the last stage blades cannot be installed? There are operation and maintenance personnel in the factory. Don't they know how to overhaul? The answer is really not! The maintenance of the rotor belongs to a special type of work. At the beginning, this work can only be performed by the original manufacturer of the steam turbine rotor. Later, with the increasing in the number of domestic units, under the premise that the technicians of steam turbine manufacturers were too busy, a group of skilled workers who understood the specific installation work of steam turbines and often cooperated with the manufacturer's technicians to repair the rotors gradually mastered the replacement of steam turbine blade skills. This is a special team. They belong to the steam turbine installation and maintenance personnel, but they can perform rotor maintenance, while not all turbine installation and maintenance personnel can. The installation of the last stage blade can only be completed by the technical personnel of the original steam turbine manufacturer or the special skilled workers mentioned in the text.

4. Precautions after the last stage blade is installed

What is the most important thing after the last stage blade is installed? It's dynamic balance! Dynamic balancing is not the job of rotor maintenance personnel. To be precise, dynamic balance testing is another independent profession. Although it is related to steam turbines, professional knowledge and experience are related to maintenance and installation personnel.

Many times, the owner often complains why he can't arrange a dynamic balancer to serve as he wanted. In fact, this is related to the small number of technicians who can do dynamic balancing and the tight work cycle. Sometimes, it is difficult for dynamic balancing professionals in China to buy air tickets to fly to foreign construction sites at any time, especially since the 2019-Covid, restrictions on entry and exit visas for technicians, and quarantine for round trip is inconvenient, and owners need to understand more , schedule and plan ahead.

The earlier communication and progress got in touch will be more useful at this time.

HOW TO CHOOSE FAN SPARE PART MANUFACTURE?

Today, we just want to share our experience for the fan spare part replacement. How to choose one fan manufacture in China and how to know whether they can fulfill your inquiry.

Take an example, we have one customer in Indonesia, which is very big and national company. We have built their steam supply boiler package with local famous construction company. The boiler are 2 sets 280 T CFB type.
The problem the customer faced recently after 8 years operation is how to make sure the spare part can be replaced correctly. Like the coupling of Recycling Fan, several years, they did not clear that for Chinese product.

We supplied the Recycling Fans to the customer already 10 years ago. The user need buy some part of the fan by themselves. Now, after several trying, one of their maintenance manager told me, “I am not sure whether this part is correct or not from the original fan manufacture” Let’s check their purchase record. The original fan manufacture officially replied to us that they already stopped this small capacity flow fan production, now, coming the question, how the user get the part from same name manufacture. After we read all “technical data file” from the user, we found one thing why the user thought they bought from original manufacture. If the Chinese Company registration passed, the company using one similar name which absorb customers. Like the name original manufacture, which the company registered as “ # # # factory YYY branch”. The user completely understand that the branch should be subsidiary of the # # # factory, but in China Registration, it might be different companies.

The most import thing is for spare part of Fans, no matter, Primary Draft fan, Induced draft fan or Recycling fan, if there is detail information of the fan, like name plate or dimension of important location, it can be fabricated by the formal manufactures.
It is just like not all parts purchasing based on the same name or similar name the correct one you need. How to find one formal manufacture / supplier to supply to you the correct product with service is more important.

If you want to know more, you can try to find the following or contact us.
https://www.qdpower-engineering.com/

Enamel Tube Air Preheater used in CFB boiler
The CFB boiler fuel is burned in a fluidized state in the furnace. After combustion, the tiny solid particles are carried by the flue gas and passed the furnace. After being separated by the separator, the fly ash enters the tail flue duct with the high-speed flue gas. The quantity of fly ash is small, but the particle size is much larger than that of the pulverized coal furnace. If the separator effect is poor or the flue gas flow rate is large during operation, the heating surfaces such as economizer and air preheater will be seriously worn. In order to solve the problem of air preheater in circulating fluidized bed furnace, our company has developed a specially suitable enamel steel tube air preheater.

（1） Material Component
The preheater tube box is composed of many thin-walled enamel tubes and steel plates. The enamel steel tubes are the wear-resistant enamel HTB-01 developed by our factory, which is evenly coated on the outer surface or inner surface of the tubes, and then sintered at high temperature to form Green composite enamel steel pipe.
（2） Structural Arrangement
The preheater adopts horizontal arrangement or vertical arrangement. When the horizontal arrangement is adopted, the air flows in the pipe, and the flue gas scours the enamel surface outside the pipe. The pipes are usually arranged in series. The pipes and the tube sheet are mainly sealed with heat-resistant packing, and can also be welded and sealed according to the needs of users. Enamelled steel pipes are usually Take φ40 or φ50 tubes. When the vertical arrangement is adopted, the air flows outside the pipe, and the flue gas scours the enamel surface in the pipe. The pipes are usually arranged in staggered rows. The pipes and the tube sheet are mainly welded and sealed, and heat-resistant packing can also be used according to user needs, such as taking φ40 or φ50 tubes.

（3） Performance Characteristic
① The enamel steel pipe of the preheater is not easy to be broken, has no cracks on the surface, wear resistance, acid and alkali corrosion resistance, high smoothness, small flue gas flow resistance, and is not easy to block ash;
② The remarkable feature of the preheater is that it is resistant to flue gas erosion and abrasion;
③ When the preheater is arranged horizontally, the flue gas side convection heat release ability is enhanced due to the lateral scouring of the tube bundle by the flue gas. Under the same heat transfer coefficient, the tube wall temperature is higher than that of the ordinary steel tube vertical preheater. , the overall heat transfer coefficient is greatly improved;
④ When the preheater is sealed with heat-resistant packing, only the pipe can be replaced after the pipe is damaged, which is convenient for maintenance;
⑤ This preheater is mainly suitable for circulating fluidized bed furnaces with serious flue gas wear.

detail to product: https://www.qdpower-engineering.com/Air-Preheater-pd43598194.html