Rectangular aluminum furnace

1. Description of the buyer's current situation:

1.1 Product: Equal-level casting aluminum plate ingot.

1.2 Fuel: natural gas.

1.3 Raw materials: Aluminum ingots and various aluminum reflow materials.

1.4 Workshop conditions: provided by the buyer.

1.5 The buyer plans the furnace type: one 50T rectangular aluminum melting furnace and one 25T tilting aluminum melting furnace.

1.6 Other requirements: Adopt energy-saving thermal storage gas combustion system.

1.7 Environmental protection requirements: separately configured by environmental protection professional manufacturers.

2.Configuration furnace type process description and technical description：

2.1 Process description:

a. A 50T rectangular aluminum melting furnace and a 25T rectangular tilting aluminum smelting furnace are adopted. The single furnace body has the characteristics of good heat insulation performance and no flue gas heat loss.

b. Using natural gas as fuel, a single 50T rectangular aluminum melting furnace is equipped with a 500 type regenerative gas combustion system, and each 25T rectangular tilting aluminum melting furnace is equipped with a 300 type regenerative gas combustion system. The system has operation It is simple, safe and reliable, and has obvious energy-saving effects. Compared with ordinary combustion systems, it can save more than 35% of energy.

c. Each aluminum smelting furnace is responsible for the intermittent addition and melting of solid aluminum, alloy preparation, refining and degassing, standing insulation and casting water discharge.

d. Each rectangular aluminum smelting furnace can be equipped with a smoking hood. The flue gas discharged from the furnace mouth is introduced into the main exhaust of the workshop through the furnace hood and low-temperature smoke pipe, and the hot smoke is discharged from the regenerative combustion system. The gas is connected to the hood of the furnace mouth or the main exhaust pipe of the workshop. All the flue gas is introduced into the environmental protection dust removal system configured outside the workshop through the main exhaust pipe and discharged after reaching the standard (all main exhaust pipes in the workshop and environmental dust removal outside the workshop). The system is configured separately by the buyer).

Photo of the site of the furnace group (reference)

2.1 Furnace group composition and structural characteristics:

50T Rectangular Regenerative Aluminum Melting Furnace:

The aluminum melting furnace consists of a hearth furnace (including a steel structure furnace shell and furnace bottom, lined with refractory materials and heat insulation materials), a vertical hydraulic lifting furnace door and cylinder pressing device, a regenerative gas combustion and air supply system , Stove mouth smoke cover and branch exhaust pipe, stove control system and other components.

2.1.1 Furnace steel structure: Furnace group steel structure: The furnace body steel structure adopts all-steel welded structure. The outer shell is made of 10mm thick high-quality Q235 steel plate and profile steel. The furnace bottom is made of 12mm thick high-quality Q235 steel plate and steel. Outer reinforced welding. The whole shell forms a mesh-like reinforced steel structure to ensure that the structure has good rigidity and air tightness, and can fully withstand the mechanical and thermal stress of the furnace.

2.1.2 Furnace refractory materials description:

a.The aluminum smelting furnace lining slag line and the following working layers are made of special non-stick aluminum high-strength casting (block type) casting (80A grade), and the working layers above the slag line are made of high-grade alumina bricks.(LZ-75, standard brick unit weight ≥4.4Kg / block) masonry.

b,The furnace roof adopts a flat-top hanging structure (anchor bricks and heat-resistant anchors are suspended), the melting furnace furnace roof is cast in an integral shape, and the castable is cast with steel fiber reinforced castable (870F grade);

b,Mullite high-strength wear-resistant castable (521C or 9606F) is used for lifting furnace door, both sides of furnace door and slag picking part of furnace door.

C. Insulation layer: It adopts combination of floating bead insulation brick (NG-0.8), thermal castable (B-0.8, B-1.6) calcium silicate board (P-0.2) and high-aluminum fiber felt and fiber paper.

d. Furnace slurry: lined with high alumina bricks above the liquid level

High temperature cement and super high alumina phosphate (water glass) mud (LN-80) are used. All insulation bricks are made of three-grade refractory wet-wet.

The diagram is as follow

Furnace wall masonry composition diagram (reference)

Furnace door structure:

a,a. Both adopt electric up and down lift furnace door structure to facilitate the large amount and rapid addition of aluminum

b. The furnace door / frame is surrounded by block heat-resistant cast iron on the furnace door / frame main frame with bolts, and appropriate gaps are left to prevent the furnace door / frame from being deformed due to uneven heating;

c. Lifting: It is equipped with a lifting motor, sprocket, chain and counterweight bucket. The motor is used to directly lift the counterweight bucket, and the work is simple and reliable. Compacting: using cylinder compaction to improve the reliability of the furnace door. Control: remote remote control ;

d. The guide door chute is installed on the furnace door counterweight barrel to ensure that the counterweight barrel does not shake when the furnace door is lifted;

e. A slag guide plate is arranged at the lower part of the furnace door to allow the aluminum slag to enter the slag hopper smoothly and prevent the high temperature aluminum slag from deforming the furnace steel structure;

f. Sealing: grooved castings are used around the furnace door, high-temperature fiber packing is inlaid in the groove, and ejection and positioning adjustment screws are provided. Solve the packing wear problem by adjusting the screws, ensure the sealing performance of the furnace door and prolong the service life of the fiber packing, and prevent the flame from leaking around the furnace door;

2.1.2 ,Configuration of Regenerative Gas Combustion System for Aluminum Melting Furnace:

The newly developed gun-free energy-saving regenerative combustion system is adopted.

A single rectangular aluminum melting furnace is equipped with one (2) XR-D500W gunless regenerative gas combustion system. The specific configuration and function are described as follows:

Basic principle of regenerative burner

The regenerative burner used in this project uses the latest technology in the field of efficient combustion. Efficient combustion comes from the periodic alternating combustion of a pair of burners, which heats the air with flue gas to obtain high-temperature combustion-supporting air. When one burner burns, the other burner sucks high-temperature smoke, which heats the heat storage body.

When the next cycle is reversed, the originally burned burner begins to burn. At this time, the combustion air flows through the high-temperature heat storage body and is heated. The original burned burner starts to suck and continues to heat the high-temperature smoke Store in thermal storage. In this way, the combustion air at room temperature can be heated to a temperature that is only 100 ° C lower than the temperature of the flue gas in the furnace, thereby obtaining extremely high heating efficiency.

Targeted technical solutions

A. The regenerative burner is a bright flame low NOx regenerative burner designed according to the actual heating process of aluminum melting. It has two flame modes specially designed (low temperature and high temperature combustion in the furnace and high temperature and low nitrogen combustion technology in the furnace). It can maximize the use of flame radiation and convective heat transfer at different stages of aluminum melting, improve heating efficiency and reduce oxidative burnout, and at the same time, greatly reduce NOx emissions.

B. The complete combustion control system will also include: a reversing valve and its pneumatic actuator for reversing control; a highly efficient premixed ignition gun; a main fire UV flame monitor and an ignition gun ion flame monitor for flame safety monitoring Natural gas flow size fire control valve group; automatic adjustment of combustion air flow frequency converter; providing a PLC control panel with human-machine interface, which is specially suitable for the needs of aluminum melting furnace combustion control, and can provide accurate and reliable furnace gas temperature control ( Or aluminum temperature control), burner reversing control, other measurement display, alarm and other functions.

Burner

A. Regenerative burner:

• a. According to the user's specific situation and requirements, the site layout design can be targeted (upper or lower, reasonable placement) to ensure the best application results.

• b. The air and gas are fully mixed and the combustion efficiency is high;

• c. Application of air classification technology.

• d. It adopts the air inlet method of the front end of the burner, and a movable end cover

door is provided at the rear end of the burner, which can greatly facilitate the cleaning of the ash accumulation in the burner or the fire mouth when the furnace is heated.

B. Regenerative box:

• a. The wall of the cabinet is solid and the heat insulation performance is very good: the internal working temperature is above 1000ºC, the external surface temperature is below 150 ° C, and the service life of the lining material can reach more than ten years, which can be arranged above and below according to the site conditions;

• b. The maintenance is simple and convenient. No need to move or disassemble the burner when performing maintenance on the heat storage body. The heat storage ball filling and discharge cover of the heat storage box adopts a door-shaped structure, which is extremely convenient to open and convenient for maintenance and repair Hot ball cleaning.

• C. Heat storage body: Steel jade ball with diameter φ25 mm and 95% alumina content is used. Its characteristics are: a. Large heat storage capacity, fast heat absorption and heat release;

• b. Strong thermal shock resistance, strong thermal shock resistance, stable performance and long life; c. Not easy to block, just wash with water, very easy to maintain;

Directional valve

The high-performance pneumatic reversing butterfly valve (flue gas reversing valve, combustion air reversing valve) is used to control the flow of smoke and combustion air.

a. The four directional valves are independent of each other and do not interfere with each other, which is convenient for maintenance;

b. The work is accurate, stable and reliable, the failure rate is extremely low, and the service life can reach more than 1.2 million times. c. When the furnace is stopped, the directional valves can be fully closed to prevent heat loss in the furnace;

Combustion control

aa, can achieve accurate fire control over the entire range of combustion power;

b. It can realize automatic switching of flame mode under different furnace temperatures, make full use of the advanced nature of regenerative burners, and obtain the best thermal efficiency;

Combustion safety

• a.Using the main flame and ignition gun flame UV monitor and ion monitor to ensure the safety of the ignition and main gun flame operation;

• b. The main gas pipeline is equipped with a safety shut-off valve to ensure compliance with safety standards.

  
  

• c. The main gas pipeline is equipped with a gas pressure transmitter, and the pressure set by the program is normally used to protect the safety range to ensure the safety of gas operation;

• d. The ignition gas pipeline is equipped with functions such as a gas pressure regulating valve and emergency shutdown to ensure the stable and safe operation of the ignition gun. e. Safety procedures such as ignition process and flameout protection that meet the requirements of the NAPF standard.

Burning system temperature detection system

Burning system temperature detection system

A temperature-measuring thermocouple is installed on the smoke exhaust pipe in front of the induced draft fan to measure the temperature of the exhaust gas. The measured temperature is transmitted to the PLC system and displayed on the operation screen. Forced switching combustion.

Combustion system technical specifications

The 50T aluminum melting furnace of this project is equipped with an XR-D500W regenerative gas combustion system, which uses natural gas as fuel. The melting furnace can meet the requirement of ≥8T / h maximum melting speed.

Connected to the burner and air valve block will provide natural gas and air to the burner body, and the gas will be sent to each burner individually. It can provide the optimal combustion flow rate, air flow rate and power adjustment ratio according to the needs of melting and heating.

The two burners are installed on the side wall opposite the center of the shaft furnace, and the downward tilt angle of the burner head is generally fixed at 15 °.

Related technical data

a. Fuel: natural gas

b. Low calorific value of gas: ≥8400Kcal / Nm3

c. Maximum natural gas consumption: Melting furnace: Max480Nm3 / h

d , Burner type: Regenerative

e. Thermal storage medium: Ø25 steel jade ball

f. Amount of single set of heat storage ball: 2750Kg / box

j. Number of burners: one pair (2)

h. Air temperature after preheating: ～ 950 ℃

i. Exhaust gas exhaust temperature: ≤180 ℃

Ignition and flame monitoring system

a. Each burner is equipped with a set of automatic ignition system, including ignition gun, ignition transformer, ignition controller, gas ignition solenoid valve, ignition electrode and other components, and a special ignition flame detector, in the combustion stage The flame is continuously monitored to ensure that the ignition flame is stable. Once the flame is extinguished, immediately cut off the main flame and sound and light alarm to ensure the safety of combustion.

combustion.

c. The ignition burner is set next to the main burner and can be controlled independently. It can also be manually controlled on the electric control cabinet (for debugging). At the same time, beside the main burner, there is also an ultraviolet flame detector (UV probe). When the main burner is burning, the main burner is continuously monitored to ensure further combustion safety.

d. If the ignition gun or main flame goes out during operation, the controller will close all solenoid valves and display the alarm to ensure the safety of combustion.

e. Each ignition system is equipped with independent ignition and air-cooled protection small fans (with variable frequency speed regulation), and the fan power is 3 KW.

f. Ignition and air-cooling protection fan runs at a set high frequency, and automatically runs at low frequency when the system is stopped to protect the fire detection probe and save power to the maximum.

Combustion air system

a. Combustion-supporting wind system includes combustion-supporting fan, stainless steel bellows, air pressure switch, pneumatic reversing butterfly valve and pipeline and other components.

b. Combustion air blower and combustion air pneumatic directional valve are key components for the reliable operation of the system.

High quality air cylinder and reply sensor method, with extremely high operating reliability.

c. When the system is running, under the control of the PLC system, the natural gas valve can be opened and burned only when the pressure of the combustion air is appropriate and the reversing butterfly valve is in place. In contrast, the combustion air valve can only be closed if the natural gas valve is closed in place.

d. Combustion air volume is preset and controlled by the control system frequency converter according to the furnace temperature control requirements.

Exhaust system

The smoke extraction system exhausts the smoke through the smoke extraction fan. The smoke extraction control butterfly valve switch of the smoke extraction system is linked with the combustion air pneumatic butterfly valve. The smoke exhaust volume of the induced draft fan is controlled by the control system inverter, that is, the large and small fire corresponds to the corresponding set frequency. In order to ensure that the combustion flame is normal and the furnace pressure is within the allowable control range.

a. The smoke exhaust system consists of a set of smoke exhaust fans, smoke exhaust pneumatic reversing butterfly valves, stainless steel bellows, and smoke exhaust pipes. b. The exhaust fan is carefully selected and configured to achieve reliable operation without maintenance for 365 days a year, especially using a water-cooled structure (the fan comes with air cooling).

c. The exhaust fan and the casing of the exhaust fan adopt a high temperature resistant design (SUS316 material), and the motor adopts a high temperature motor, which is designed to withstand a temperature of 350 ° C.

d. The temperature of the flue gas finally discharged by the combustion system depends on the switching period of the nozzle and the temperature in the furnace. It is usually about 150 ° C, and the maximum does not exceed 200 ° C.

e. The main smoke volume is controlled by the PLC system and the inverter according to the furnace temperature control requirements.

Temperature monitoring

The thermocouples provided with the device include:

--Measuring furnace temperature thermocouple (with silicon carbide protection tube) 1

--1 thermocouple for exhaust temperature measurement

Electrical control system

• a. The process control of this control system is composed of German Siemens S7-1200 program controller. The hardware includes CPU module, digital input module, digital output module, analog input module, analog output module, power module, etc. Easy to maintain and maintain, an operator panel is set up, which can easily set and modify process parameters and process variable control parameters.

• b. The programming software includes the S7-1200 basic software. The programming software is transparent, understandable and easy to maintain.

• c. The control system includes: temperature control, automatic and manual switching control for large and small fires.

Combustion control system operation interface:

The entire system operation is centralized through a large-screen touch screen, which has the characteristics of simple operation and clear interface.

500 type regenerative combustion system configuration table:

25T Rectangular tilting type aluminum liquid holding furnace part:

Rectangular tilting type aluminum smelting furnace consists of a hearth furnace (including all-steel structure furnace shell and furnace bottom, lined with refractory materials and heat insulation materials), a vertical electric lift furnace door, a 300-type regenerative gas combustion and air supply system, Furnace hood, smoke exhaust pipe, furnace control system, etc.

2.1.1 ,Refractories description: same as 50T rectangular aluminum melting furnace.

2.1.2 ,Configuration of regenerative gas combustion system for tilting holding furnace:

Each holding furnace is equipped with a XR-D300W regenerative gas combustion system. Except for different specifications, the specific configuration and function description are the same as those of the aluminum melting furnace.

2.1.3 ,Reinjection nozzle: Adopt advanced rotary reinjection nozzle structure, so that the aluminum liquid level in the furnace and the aluminum liquid level in the flow tank have no drop or only a small drop to ensure that the oxide film on the aluminum liquid level is Damaged to avoid secondary contamination such as aluminum rolling, re-aspirating and slag inclusion.

2.1.4 .Oil cylinder and hydraulic system requirements: The holding station tilting hydraulic system pump station has a vertical overall structure, that is, the hydraulic pump motor unit and control valve table are concentrated on the oil tank. The pump and main valve parts are imported products.：

a. A total of 2 hydraulic pumps, that is, two hydraulic pumps, one working and one standby (reserve each other).

b. It can realize the action requirements of rising, stopping, falling, fast-falling, etc., and manual and automatic working states when the static furnace is tilted.

c. Automatic return in case of power failure.

d. A hose anti-fall valve is installed at the outlet of the tilting cylinder. Once the pipeline is cracked, avoiding the rapid return of the static furnace to cause an accident.

e. For tilting hydraulic cylinders, imported seals, composite material guide rings, longer guide distances, and

The head of the plug rod adds joint bearings and other measures to improve the friction and stress of the cylinder movement, so that the hydraulic cylinder can move smoothly during no-load and load test without creeping.

Tilting furnace control requirements:

The tilting furnace control mode is position control. The tilting angle of the furnace body is 22.5 °. The tilting furnace operation mode is divided into automatic and manual. The manual mode is divided into fast rise and fast drop. The automatic mode is only slow rise and slow drop (that is, normal working state). , The whole control is controlled by PLC and flume laser rangefinder.

Laser level control system:

2.1.5 a. Using German SICK laser rangefinder:

2.1.6 b. In order to achieve high-level flow tank liquid level control, this equipment uses a laser liquid level control system, and the liquid level control accuracy can reach ± 2mm. The laser distance measuring device is set at a certain height (less than 2 meters) above the flow channel, and it is protected by forced cooling with compressed air.

c. A set of automatic pneumatic flow control device is set at the position of the water outlet of each furnace. The flow control device is controlled by the signal and control system of the laser rangefinder to achieve the purpose of controlling the flow of aluminum liquid.,

Furnace door structure: It adopts the form of vertical hydraulic lifting furnace door and cylinder compaction. Except for different specifications, its configuration is the same as that of a 50T rectangular melting furnace.

2.1.7 ,Furnace exhaust pipe:

a. Both the 50T aluminum melting furnace and the 25T rectangular tilting smelting furnace are equipped with a low-temperature smoking hood at the mouth of the furnace, and are introduced into the main exhaust smoke of the workshop through the exhaust branch pipe.

b. The hot flue gas discharged through the regenerative combustion system can be introduced into the main exhaust pipe of the workshop (or inside the furnace hood) through the smoke pipe.

c. The main smoke exhaust pipelines inside and outside the workshop and the environmental dust removal system outside the workshop are separately configured by professional environmental protection equipment manufacturers.

2.1 Technical performance of the furnace group:

2.2.1 Furnace group use: It is mainly used for continuous melting of aluminum material, and to ensure continuous water casting and rolling of the holding furnace

2.2.2 Adapted raw materials: aluminum ingots and a small amount of self-produced recycled materials

2.2.3 Furnace structure: The aluminum melting furnace has a rectangular flat-top structure, and the heat preservation furnace has a rectangular tilting furnace structure.

2.4.5 Out-of-bath temperature of molten aluminum: 700 ～ 760 ℃ (determined by buyer)

2.3.6 Melt temperature difference: ± 5 ℃ (refining and degassing are complete)

2.4.7 Furnace door opening and closing form: The aluminum melting furnace is a hydraulic lifting type, and the holding furnace is a manual all-steel structure hinged sealed furnace door.

2.4.8 Fuel: Natural gas

2.4.9 Temperature measurement method: continuous measurement and display of furnace gas temperature, the temperature of aluminum liquid is measured by hand-held thermometer

2.4.7 2.4.10 Burner form: all adopt regenerative gas combustion system

2.2 Technical parameters of various furnaces:

2.3 Details of the composition of the masonry and shell of the 50T aluminum melting furnace (except for the thickness of the 25T tilting furnace, the masonry composition is basically the same)

3,Furnace Group Price Details:

4,Seller's content

50T Rectangular Regenerative Aluminum Melting Furnace

4.1 Aluminum melting furnace -

(including shell parts and various refractory materials) 1 set

4.2 500 regenerative gas combustion system 1 set

4.3 Electric lift furnace door 1 set

4.4 Furnace smoking hood and exhaust pipe 1 set

4.5 Stove electrical control cabinet 1 set

25T Rectangular Tilt Regenerative Aluminum Melting Furnace

5,Buyer and seller equipment and installation and docking instructions:

6,Quality assurance and after-sales service:

7,Random spare parts:

8,Technical documentation provided (written or electronic):

9,Design, manufacture and installation standards:

1,Design and manufacturing standards:

1.1 ,It adopts advanced and mature mechanical and electrical control technology; all design adopts computer-aided design (CAD); marking conforms to GB / T14692-93, GB458.1-84, GB4458.4 ~ 5-84 standards.

1.2 ,Manufacture strictly in accordance with the materials, dimensions, tolerances, heat treatment requirements, technical requirements, and process requirements required by the drawings

1.3 ,The standard parts are selected from well-known manufacturers' products and undergo strict inspection and acceptance; electrical control devices and other electrical appliances adopt well-known domestic brands and imported brands.

1.4 ,Forged castings and machined parts meet the general technical requirements of the respective metallurgical industry standards (YB).

1.5 ,1.5 The main purchased parts come with a product qualification certificate and instruction manual.

2,Installation standards and requirements:

2.1 ,《Code for construction and acceptance of industrial furnace masonry》 GBJ211-87

2.2 ,《Industrial furnace masonry engineering quality inspection and evaluation standards》 GB50309-92

2．3《Code for construction and acceptance of steel structure engineering》----------------GBJ 50205-95

2．4,《Welding standard》 GB/T5000.3-1998

2．5,《Rust level and derusting level of steel surface before painting》 GB8923

10,Business Terms：

10.1 ,Delivery time

a,The seller shall provide the buyer with the basic construction condition map within 20 days from the date of receiving the advance payment;

b. The buyer shall promptly confirm in writing to the seller after receiving the layout plan of the furnace unit and the diagram of the basic construction conditions;

c. The seller has made the furnace unit eligible for delivery within 50 days from the date of confirmation of the basic plan.

In the field and with the construction conditions, the complete set of furnaces has the conditions of the oven within 70 days;

d. The buyer shall have on-site installation conditions at least 90 days before the date of delivery;

e. On-site production and construction conditions mean that the workshop is connected to water and electricity, the foundation and the platform in front of the furnace are completed, the floor of the workshop is completed, and other civil works related to the construction of the furnace are completed and qualified by the seller. The vehicle can be used. Cranes are provided free of charge);

f. The buyer shall notify the seller in writing after having the on-site construction conditions. The seller shall accept the on-site construction conditions and issue an acceptance report. When the acceptance fails, the buyer shall promptly rectify and improve until the re-acceptance is qualified and the delivery period is extended to Until the acceptance date (even if construction has begun, the delivery period is also extended);

10.2 ,Acceptance standards and methods

a,The buyer provides a written acceptance notice and is responsible for organizing the acceptance within 20 days after the equipment installation is completed;

b. The buyer and the seller jointly inspect and accept according to the relevant clauses of the technical agreement of this contract, and take the indicators produced in the continuous production of 6-8 furnaces for 2-3 furnaces as the acceptance results;

c. If there is no acceptance or failure to accept within 10 days from the date of commissioning or within 45 days after the completion of production and installation due to non-seller reasons, the acceptance is deemed to be qualified;

d. During the acceptance test, the buyer must operate in accordance with the requirements and operating procedures, and cooperate with the seller to adjust the test and accept.

10.3,After sales service and quality assurance

a,The main body equipment warranty period is 365 days, and the warranty period for other special accessories and general equipment is 180 days, calculated from the date when the furnace unit is qualified for acceptance;

b. The free warranty period is one year (normal damage). The repair and all costs incurred due to the quality of the equipment during the warranty period shall be borne by the seller, and the repairs and all costs caused by the buyer due to improper operation, use, and maintenance shall be borne by the buyer;

c. The seller provides the buyer with special accessories within one year for free (normal damage, ready for delivery);

d. When there is a quality problem that the buyer cannot resolve by itself, the seller arrives at the buyer's site to deal with the problem within 48 hours after receiving the buyer's notification;

e. The seller trains 2-3 operators for the buyer for free.

10.4,Mode of transportation and cost, plplace of delivery

a,The seller is responsible for the long-distance transportation and costs to the port, and the customs and delivery of the goods to the port of destination shall be borne by the buyer.

b,Place of delivery: The seller is responsible for shipping all the goods to the port designated by the buyer.

10.5,Payment terms

a,Payment method: bank transfer;

b. The contract becomes effective after the advance payment is 30% of the total contract amount.

c. The seller's shell parts and materials are ready to be paid 60% within ten days before shipment (the buyer can come and accept). d. The seller's construction personnel shall pay 5% within three days after arriving at the construction site.

e. The remaining balance of 5% shall be paid within six months of normal use;

10.6,Equipment installation and commissioning and other cost descriptions:

a,According to the equipment installation progress requirements, the seller dispatches the required technicians in batches for on-site construction, installation and debugging.

b. The buyer shall bear the following costs of all dispatched personnel of the seller: local room and board, visa costs, air tickets to and from China, and other transportation costs. A subsidy of USD 70 per person per day abroad (the cost of the subsidy starts from the date of arrival).

c. The seller bears the following expenses for dispatching personnel: domestic board and lodging and transportation costs.