Tag Archives: green agricultural

China Standard Commercial Sawtooth Greenhouse Plastic Film Green House Multi-Span Agricultural Greenhouse with Best Sales

Product Description

Commercial Sawtooth Greenhouse Plastic Film Green House Multi-span Agricultural Greenhouse

 

 

Multi span plastic film agriculture greenhouse is a greenhouse with film as the main transparent covering material, which is usually divided into single-layer film greenhouse and double-layer film greenhouse. The film greenhouse built by our company is low cost, economical, practical, beautiful generous, convenient installation and durable.

Characteristic

1. Good ventilation system,Roof / side ventilation.
2. The height can be adjustable, also meet the needs of different clients personalized
3.Excellent light transmittance performance;
4.Greenhouse main structure with 25 years life time.
5. Economical and practical,Low invest and low running cost in winter;

If you guys want more information of them, just contact me directly, we can recommend the suitable ideas in you local situation.

Frame structure

Galvanized steel materials

Type of Construction

Arched/Serrated Roof

Covering Materials

Plastic film

Span width

6-10m

Height

3-5m

Wind load 

0.5KN/m2

Snow load 

0.35KN/m2

Rainfall

140mm3/h

Product Specification

Item

Specification

Type

multi span greenhouses

Model number

customized

Product name

Multi span plastic film greenhouse

Covering

plasstic film

Thickness

8-12mm

Frame material

Hot Galvanized Steel

Features

eco-friendly

Application

vegetables/flowers/fruits

Span width

8m/9m/9.6m/12m/customized

Eaves height

3-8m

Warranty

3 years

Optional system

ventilation/cooling/heating/shading/hydroponics/lighting/irrigation/fertilization/seedbed system

Company Profile

 

AIXIANG Agriculture Technology Co.,Ltd.is a professional engaged in greenhouse technology development,engineering design,production and processing,product sales,installation and service as 1 stop solution.Within modern production equipment,professional production technology and first-class production plant,high-quality designer,R&D personnel,production and construction personnel.

We AIXIANG focus on developing the Plastic Greenhouse,PC-Sheet Greenhouse,Mutil-Span Greenhouse,Solar panel Greenhouse,Sunlight Greenhouse,Venlo glass greenhouse.And the greenhouse complementary is cooling equipment,internal / external shading equipment,fixed / mobile sprinker systems,movable seedbed,fertilization systems and other greenhouse system.

Advantage

  1. Price.Our price is favorable,we can according to your order and give you some discounts;
  2. Quality.The quality of our products are superb,bcz our company always adhere to the quality oriented,and our reputation is good at home and abroad;
  3. Delivery.We can arrange shipment after you placing an order 3-30 days;
  4. Packing.The different part has different package,we according to their feature to choose the packing material,finally in the container;
  5. After-sales service.Each part has different warranty.Usually is more than 2 yesrs,the longest warranty is 15 years

FAQ

1. Are you a factory outlet or a special foreign trade company?A:We are factory direct sales, all the goods are shipped directly from the factory.

2. Does the greenhouse accept customization?A: We accept custom greenhouses of any size.

3. What is the packaging of goods?A:Greenhouse covered materials and equipment using carton packaging. Other accessories in the greenhouse using nude packing. Can be packaged according to customer requirement.

4. What is your installation and after sales?A: Installation is very simple, you can install it yourselves. We also have professional engineers to install it for you if needed. Free repair within 2 years after your purchase(including small parts).Sales 24 hours online to answer your questions,any demands or questions, please feel free to contact us.

5. How long does it take to delivery?A: The first shipment will be sent about 25 days after your first deposit.

6. Can you provide turn-key service?A: Yes, we have special team of every parts to do customer service, design, supplier selection, delivery and installation.

Calculating the Deflection of a Worm Shaft

In this article, we’ll discuss how to calculate the deflection of a worm gear’s worm shaft. We’ll also discuss the characteristics of a worm gear, including its tooth forces. And we’ll cover the important characteristics of a worm gear. Read on to learn more! Here are some things to consider before purchasing a worm gear. We hope you enjoy learning! After reading this article, you’ll be well-equipped to choose a worm gear to match your needs.
worm shaft

Calculation of worm shaft deflection

The main goal of the calculations is to determine the deflection of a worm. Worms are used to turn gears and mechanical devices. This type of transmission uses a worm. The worm diameter and the number of teeth are inputted into the calculation gradually. Then, a table with proper solutions is shown on the screen. After completing the table, you can then move on to the main calculation. You can change the strength parameters as well.
The maximum worm shaft deflection is calculated using the finite element method (FEM). The model has many parameters, including the size of the elements and boundary conditions. The results from these simulations are compared to the corresponding analytical values to calculate the maximum deflection. The result is a table that displays the maximum worm shaft deflection. The tables can be downloaded below. You can also find more information about the different deflection formulas and their applications.
The calculation method used by DIN EN 10084 is based on the hardened cemented worm of 16MnCr5. Then, you can use DIN EN 10084 (CuSn12Ni2-C-GZ) and DIN EN 1982 (CuAl10Fe5Ne5-C-GZ). Then, you can enter the worm face width, either manually or using the auto-suggest option.
Common methods for the calculation of worm shaft deflection provide a good approximation of deflection but do not account for geometric modifications on the worm. While Norgauer’s 2021 approach addresses these issues, it fails to account for the helical winding of the worm teeth and overestimates the stiffening effect of gearing. More sophisticated approaches are required for the efficient design of thin worm shafts.
Worm gears have a low noise and vibration compared to other types of mechanical devices. However, worm gears are often limited by the amount of wear that occurs on the softer worm wheel. Worm shaft deflection is a significant influencing factor for noise and wear. The calculation method for worm gear deflection is available in ISO/TR 14521, DIN 3996, and AGMA 6022.
The worm gear can be designed with a precise transmission ratio. The calculation involves dividing the transmission ratio between more stages in a gearbox. Power transmission input parameters affect the gearing properties, as well as the material of the worm/gear. To achieve a better efficiency, the worm/gear material should match the conditions that are to be experienced. The worm gear can be a self-locking transmission.
The worm gearbox contains several machine elements. The main contributors to the total power loss are the axial loads and bearing losses on the worm shaft. Hence, different bearing configurations are studied. One type includes locating/non-locating bearing arrangements. The other is tapered roller bearings. The worm gear drives are considered when locating versus non-locating bearings. The analysis of worm gear drives is also an investigation of the X-arrangement and four-point contact bearings.
worm shaft

Influence of tooth forces on bending stiffness of a worm gear

The bending stiffness of a worm gear is dependent on tooth forces. Tooth forces increase as the power density increases, but this also leads to increased worm shaft deflection. The resulting deflection can affect efficiency, wear load capacity, and NVH behavior. Continuous improvements in bronze materials, lubricants, and manufacturing quality have enabled worm gear manufacturers to produce increasingly high power densities.
Standardized calculation methods take into account the supporting effect of the toothing on the worm shaft. However, overhung worm gears are not included in the calculation. In addition, the toothing area is not taken into account unless the shaft is designed next to the worm gear. Similarly, the root diameter is treated as the equivalent bending diameter, but this ignores the supporting effect of the worm toothing.
A generalized formula is provided to estimate the STE contribution to vibratory excitation. The results are applicable to any gear with a meshing pattern. It is recommended that engineers test different meshing methods to obtain more accurate results. One way to test tooth-meshing surfaces is to use a finite element stress and mesh subprogram. This software will measure tooth-bending stresses under dynamic loads.
The effect of tooth-brushing and lubricant on bending stiffness can be achieved by increasing the pressure angle of the worm pair. This can reduce tooth bending stresses in the worm gear. A further method is to add a load-loaded tooth-contact analysis (CCTA). This is also used to analyze mismatched ZC1 worm drive. The results obtained with the technique have been widely applied to various types of gearing.
In this study, we found that the ring gear’s bending stiffness is highly influenced by the teeth. The chamfered root of the ring gear is larger than the slot width. Thus, the ring gear’s bending stiffness varies with its tooth width, which increases with the ring wall thickness. Furthermore, a variation in the ring wall thickness of the worm gear causes a greater deviation from the design specification.
To understand the impact of the teeth on the bending stiffness of a worm gear, it is important to know the root shape. Involute teeth are susceptible to bending stress and can break under extreme conditions. A tooth-breakage analysis can control this by determining the root shape and the bending stiffness. The optimization of the root shape directly on the final gear minimizes the bending stress in the involute teeth.
The influence of tooth forces on the bending stiffness of a worm gear was investigated using the CZPT Spiral Bevel Gear Test Facility. In this study, multiple teeth of a spiral bevel pinion were instrumented with strain gages and tested at speeds ranging from static to 14400 RPM. The tests were performed with power levels as high as 540 kW. The results obtained were compared with the analysis of a three-dimensional finite element model.
worm shaft

Characteristics of worm gears

Worm gears are unique types of gears. They feature a variety of characteristics and applications. This article will examine the characteristics and benefits of worm gears. Then, we’ll examine the common applications of worm gears. Let’s take a look! Before we dive in to worm gears, let’s review their capabilities. Hopefully, you’ll see how versatile these gears are.
A worm gear can achieve massive reduction ratios with little effort. By adding circumference to the wheel, the worm can greatly increase its torque and decrease its speed. Conventional gearsets require multiple reductions to achieve the same reduction ratio. Worm gears have fewer moving parts, so there are fewer places for failure. However, they can’t reverse the direction of power. This is because the friction between the worm and wheel makes it impossible to move the worm backwards.
Worm gears are widely used in elevators, hoists, and lifts. They are particularly useful in applications where stopping speed is critical. They can be incorporated with smaller brakes to ensure safety, but shouldn’t be relied upon as a primary braking system. Generally, they are self-locking, so they are a good choice for many applications. They also have many benefits, including increased efficiency and safety.
Worm gears are designed to achieve a specific reduction ratio. They are typically arranged between the input and output shafts of a motor and a load. The 2 shafts are often positioned at an angle that ensures proper alignment. Worm gear gears have a center spacing of a frame size. The center spacing of the gear and worm shaft determines the axial pitch. For instance, if the gearsets are set at a radial distance, a smaller outer diameter is necessary.
Worm gears’ sliding contact reduces efficiency. But it also ensures quiet operation. The sliding action limits the efficiency of worm gears to 30% to 50%. A few techniques are introduced herein to minimize friction and to produce good entrance and exit gaps. You’ll soon see why they’re such a versatile choice for your needs! So, if you’re considering purchasing a worm gear, make sure you read this article to learn more about its characteristics!
An embodiment of a worm gear is described in FIGS. 19 and 20. An alternate embodiment of the system uses a single motor and a single worm 153. The worm 153 turns a gear which drives an arm 152. The arm 152, in turn, moves the lens/mirr assembly 10 by varying the elevation angle. The motor control unit 114 then tracks the elevation angle of the lens/mirr assembly 10 in relation to the reference position.
The worm wheel and worm are both made of metal. However, the brass worm and wheel are made of brass, which is a yellow metal. Their lubricant selections are more flexible, but they’re limited by additive restrictions due to their yellow metal. Plastic on metal worm gears are generally found in light load applications. The lubricant used depends on the type of plastic, as many types of plastics react to hydrocarbons found in regular lubricant. For this reason, you need a non-reactive lubricant.

China Standard Commercial Sawtooth Greenhouse Plastic Film Green House Multi-Span Agricultural Greenhouse     with Best SalesChina Standard Commercial Sawtooth Greenhouse Plastic Film Green House Multi-Span Agricultural Greenhouse     with Best Sales

China supplier Greenhouindustrial Commercial Low Cost Multispan Agricultural Greenhouses Structure Green Housese with Irrigation Hydroponic System near me manufacturer

Product Description

Planting factory for various of vegetable in greenhouse
Plant factory is a high-efficiency agricultural system that realizes annual continuous production of
crops through high-precision environmental control in the facility. It uses computers to automatically
control environmental conditions such as temperature,humidity, light, CO2 concentration and nutrient
solution for plant growth. Labor-saving production that is not or rarely restricted by natural conditions

Classification of closed plant factory facilities

1. Idle factories and basements

Transforming these idle land resources into closed plant factories for high-yield, high-quality, and high-efficiency
plant production not only revitalizes idle resources, reduces costs, but also creates high value.

2. Abandoned containers

The artificial light-enclosed plant factory rebuilt from waste containers has the characteristics of good sealing,
high safety, good landscape, integrity, good structure, easy temperature control, convenient movement, long
service life, and strong environmental adaptability. A single box can become an independent plant factory,
multiple can also form a large plant factory, and multiple stacks can form a high-rise plant factory.

3. Foam board room

The artificial light plant factory built with foam sandwich panels has the advantages of light material, low cost,
short construction period, good sealing, etc. It can also be arbitrarily large, small, high and low, which is
convenient for the construction plHangZhou of internal facilities , widely favored by plant factory builders.

4. Inflatable membrane

Inflatable membrane is a fully enclosed structural space formed after infusing air with polymer materials (film
products made of high-strength carbon fibers and aerogels). The high-level three-dimensional plant cultivation
system built in such a structural space is called an inflatable membrane enclosed plant factory.The materials of
this inflatable house are high-strength carbon fiber, aerogel membrane and air. The outside uses solar energy
as energy, the inside is information intelligence and plant factory system facilities, and the middle is air. Such
an inflatable house enclosed plant factory has the advantages of low cost, strong sealing, good integrity, and
convenient use.

Selection of the cultivation form of closed plant factory

Plane Multilayer Stereo Cultivation In the container type closed plant factory, only 2 rows of cultivation racks can be designed. Due to the constraints of height
and space, the cultivation form can only be 3 to 4 layers. This is because the plane multi-layer three-dimensional cultivation
form can only use nutrient solution water. For the cultivation technology, each floor needs a nutrient pool, cultivation board,
LED supplementary light and vegetable plants and the space occupied by the cultivation rack. Generally, each floor is 65-70 cm, so
that the space for the cultivation area that can be expanded is limited. As a result, yields and benefits can only be improved
within a certain range.
Polyhedron Stereo Cultivation The form of polyhedral three-dimensional cultivation bed can be replaced by nutrient solution hydroponics technology. Each group
of cultivation beds has only 1 nutrient pool. The utilization rate is higher, due to the realization of water, fertilizer and
gas supplementation, the plant grows faster, the cost is lower, the weight is lighter, and the yield is increased many times. If
the polyhedral cultivation form is adopted in the closed inflatable film plant To produce plants, the three-dimensional space is
larger, and the yield and benefit will be maximized
Curtain Wall Stereo Cultivation Curtain wall three-dimensional cultivation is to cultivate plants on the walls of closed plant factories or artificially designed and constructed curtain walls,Cultivation beds are set up on the walls around the container, and plants are cultivated on the cultivation beds using the Chaoxi
culture technique. A nutrient pool is set under the cultivation beds, and LED supplementary lights are installed on the top of the
container. More adequate, more reasonable layout, more convenient operation, larger cultivation area and higher yield. If more,
taller and wider plant curtain walls are set up to cultivate plants in the closed inflatable film plant factory, the yield and
efficiency will be higher.
Vertical three-dimensional cultivation Hanging the plant cultivation bed on the top of the closed plant factory, and then sowing, irrigating, fertilizing, and plant
protection on the hanging cultivation bed is not only a kind of agricultural production, but also an art of survival. In any
closed plant factory, the realization of vertical three-dimensional cultivation for agricultural production can not only expand
the area, increase yield, and increase efficiency, but also reduce costs and improve resource utilization, which is not only
environmentally friendly, but also facilitates sustainable production; not only It is easy to operate and enhances the life
experience.
Cylindrical Stereo Cultivation Plants are planted on the surface of the cylinder, the three-dimensional cultivation area is larger, and the aeroponics technology
is used, the plants grow faster. However, in the closed container type plant factory, because the environmental space is too
small, it is not suitable to use a cylindrical three-dimensional cultivation device. However, in other types of closed plants,
especially in the closed plant factories with air-filled membranes and air-tight membranes, the advantages of cylindrical
three-dimensional cultivation will be brought into play for a longer period of time

Main features
The common features of plant factories are: fixed facilities; automatic and semi-automatic control of temperature,
humidity, light intensity, light time and CO concentration required for plant growth and development by using
computers and various sensing devices; using nutrients Hydroponics technology; the quantity and quality of
products are greatly improved.

Fold and harvest fast

Through the high-precision control of the environment in the factory, the growth of plants here is almost not
restricted by natural conditions, and the growth cycle is accelerated. Lettuce, cabbage, etc. grown in the factory
can be harvested in about 20 days, while in ordinary fields , it will take 1 month to 40 days. In addition to
fast harvesting, high space utilization is also an important feature of plant factories. What we see in the factory
are the three-layer cultivation racks, which are equivalent to 3 times the open-air cultivated land of the same
size in terms of area. In addition, the planting density is high. Therefore, the output of the plant factory can reach
dozens or even higher than that of conventional cultivation. Hundred times, the cycle of seedlings is shorter,
generally about a week.

Folding Environment Requirements
The plant factory uses energy-saving plant growth lamps and LEDs as artificial light sources, and adopts 13
interrelated control subsystems such as cooling-heating bidirectional temperature and humidity control,
light-carbon dioxide coupled photosynthesis and gas fertilizer control, and nutrient solution online detection
and control. It can automatically monitor the temperature, humidity, light, airflow, carbon dioxide concentration,
nutrient solution and other environmental elements of the plant factory in real time to achieve intelligent
management.

 

Understanding the Different Types of Bearings

When you are looking for a bearing, you have many options to choose from. This article will explain the various types, functions, and working principles of different types of bearings. Once you understand the basic components, you can make an informed decision about which 1 to buy. Here’s an overview of some of the most common types. Learn more about each type below! Read on to learn about the differences between these different types of bearings! Posted in Articles

Functions

bearing
Bearings serve as an integral part of a mechanical device. These devices help transfer torque from 1 part of a structure to another. These mechanisms increase the efficiency of a shaft by increasing its life. However, the functions of bearings depend on the application of the structure. Among other functions, bearings provide support to shafts. Anti-friction bearings come in 2 types: ball and roller bearings. These components have line and point contact, which is the most common type. Archimedes’s principle states that the force is equal to the weight of the fluid that is being displaced. Bearings can transfer lateral loads to a substructure.
A bearing has 2 primary functions. The first is to prevent direct metal-to-metal contact. A bearing prevents friction, heat generation, and wear and tear of components. A bearing also reduces energy consumption. Its other purpose is to guide and support a rotating body. In addition to these functions, bearings can also reduce wear and tear on a machine. As a result, they are among the most widely used machines in the world.
Seals are a major component of a bearing. They prevent foreign materials from entering and lubricating the moving parts. The design of seal lips determines their effectiveness. Fuel economy regulations and CO2 emissions regulations are pushing the demand for low-friction bearings. However, high-performance seals do not always provide high-performance. As a result, current estimations of the friction in bearings depend on trial and error methods.
Another important function of bearings is that they transfer the load of a rotating component to its housing. This load can be axial or radial. Bearings also limit movement to predefined directions. Some types of rolling element bearings have balls or cylinders inside. These bearings are less frictional than sliding ones, thus they allow parts to move freely during rotation. These parts can then be used for various applications. So, bearings are an integral part of machines.

Types

The most common type of bearing is a plain bearing. It uses surfaces in rubbing contact to transmit movement from 1 part to another. These bearings may be discrete or may consist of a hole in a metal sleeve or a planar surface bearing another part. Some plain bearings are flanged, while others are made of a sleeve with a flange at 1 end. These bearings often give acceptable accuracy and life, but they are expensive and cannot be used in large scale applications.
Radial bearings are used when there is a need for high-speed or corrosive parts. This type of bearing also serves as a support in an intermediate situation. Its 2 components are called the base and the cover. The base and cover are connected and are arranged parallel to the main axis. This type of bearing is used in steady-state and axial motion applications. The radial bearings are also used when the shafts are long.
Angular contact bearings are another type of bearing. These are easy to install and require minimal maintenance. Their races are displaced along the axis. They are also better at handling axial loads and transferring them to the housing. These types of bearings are commonly used in pumps, automobiles, and high-speed applications. If you are looking for an affordable, reliable bearing, look no further than the angular contact bearing.
Another type of bearing is a self-lubricating bushing. These are lightweight and wear-resistant. Unlike the other types of bearing, they do not require any lubrication or maintenance. In fact, some are completely maintenance-free. But if you’re worried about maintenance, this type of bearing may be a good choice. There are many benefits of using self-lubricating bushings. It is also a good option for applications where your machine is exposed to extreme temperatures.

Working principle

bearing
A bearing has 2 primary functions: support and load transfer. In engineering applications, the bearing tends to push the load in the direction of the shaft. A radial load pushes the bearing downward and a thrust load pushes it sideways. Both types of load transfer are important in a variety of applications. The working principle of each type is described below. Listed below are the main uses for each type of bearing.
A plain bearing uses a PTFE liner on the interface of 2 moving parts. The PTFE liner acts as a lubricant and may be filtered to alter its friction. The journal bearing uses the motion of the journal to force fluid into the gap between 2 moving parts. This results in a small amount of play in the bearing. This play is acceptable for most applications. A ball bearing may have a maximum play of 2 mm for a ten-millimeter shaft.
The primary function of a bearing is to assist in rotation and to reduce mechanical friction between the 2 objects. A bearing may be installed as a separate device or as an integral part of a machine. For more complex applications, bearings are very precise components requiring the highest standards of technology. For this reason, it is important to understand the working principle of bearings. The next time you need to lift or slide a heavy object, consider a bearing.
Ball bearings are a common type of ball bearing and can be found in industrial machinery and automobiles. Their unique structure helps them support less weight. This is because they are comprised of 2 rings – an inner race and an outer race. The balls themselves have a small area of contact and transfer axial loads in 1 direction. A cage surrounds the balls and prevents them from colliding. This makes ball bearings a popular choice for many applications.

Sealing system

A bearing’s seals are vital for the operation of rolling and rotating components. These systems enable rotation and linear movement while limiting friction and dispersing stress. Without the proper seals, these components could face catastrophic failure. In addition to protecting the bearing from external forces, seals help retain lubricant inside the system and prevent harmful particles from entering the gap. A seal’s lubrication helps prevent the onset of mechanical damage and prolongs the life of the bearing.
A bearing seal is made up of 2 parts: the inner sealing element and the outer sealing element. A passageway runs through the bearing assembly to the outer seal element. A hydraulic press or pneumatic jack is recommended for installing the seal. These tools are effective in reducing deformation and improving seal installation quality. When fitting the seal, ensure that the tool does not hit the seal directly. A proper adopter will distribute the load uniformly across the seal.
The seal’s efficiency depends on its gap. A four-inch shaft seal can flow 0.5 standard cubic feet per minute. A seal’s efficiency is highly dependent on the gap size. The gap size is a cube of the flow through the system. A smaller gap size allows high flow and pressure but less leakage. If both surfaces of the seal have similar pressures and flow rates, the seal is efficient. However, a small gap reduces the pressures and reduces wear.
Mechanical seals have numerous advantages, including their ability to protect against contaminants and splashing liquids. Labyrinth seals are the first line of defense against leaks. They operate without friction. Their high level of sealing efficiency helps ensure that the bearing remains operational for long. This type of seal is made from metal plates and is designed for a wide temperature range and misalignment. Its advantages include being easy to install and offering 100% sealing efficiency.

Maintenance

bearing
Bearing maintenance is critical to ensuring that your bearings keep operating at their peak performance. Proper maintenance will improve bearing life, reduce downtime and increase productivity while reducing costs. Here is an 8-point checklist to optimize your bearings and make them last longer. To optimize their performance, you should follow these steps regularly. In case a bearing does not last long, you should replace it as soon as possible. Listed below are some tips to ensure proper maintenance.
The first step is to determine how often your bearings require lubrication. Some manufacturers recommend that you lubricate them weekly, but this can do more harm than good. Instead, use ultrasound to measure the level of friction and trend its levels. This way, you will know exactly when to grease your bearings. It’s also important to check how often they should be inspected and calibrated. A professional can provide guidance on proper maintenance.
Next, inspect your bearings for cracks and scratches. You should never install a bearing that has been dropped or scratched. Even a small crack will affect the performance of the bearing and could lead to its premature failure. A proper alignment is essential for the bearing to function properly. Make sure you have the correct tools to perform this task. These tools can help you reduce manual work and promote safe bearing maintenance. You should also ensure that the shaft and housing are clean and undamaged.
Proper maintenance can prolong bearing service life. Proper lubrication, mounting, inspection, basic condition monitoring, and dismounting can extend their life. Proper maintenance extends their lifespan and improves plant productivity. While bearings are essential for machinery, you should make sure you follow the proper safety procedures every time you work with them. These tips will also help prevent accidents and maintain your machine’s efficiency. Once you’ve followed these guidelines, you can safely inspect your bearings and ensure that they’re operating at their optimum capacity.

China supplier Greenhouindustrial Commercial Low Cost Multispan Agricultural Greenhouses Structure Green Housese with Irrigation Hydroponic System     near me manufacturer China supplier Greenhouindustrial Commercial Low Cost Multispan Agricultural Greenhouses Structure Green Housese with Irrigation Hydroponic System     near me manufacturer