Bright steel bar is carbon or alloy steel bar with shining bright surface which is improved by cold drawing, peeling, turning, grinding and polishing over hot rolled black surface bars. By cold drawing, the steel bar yield strength and tensile strength will be improved. By peeling and turning, the surface imperfections will be removed. By grinding, the diameter tolerance will be more precision. By polishing, the surface will be much more shining.
Except the shining bright surface, comparing with the hot rolled black surface bars, the bright steel bars has better surface roughness, better roundness, straightness, more precision size tolerance etc.
Heat treatment such as annealing, normalizing, quenching and tempering will be done before do cold finishing on the hot rolled bar to get bright steel bar, in such condition, the steel Bright Bar will get most suitable mechanical properties to meet different application requirement.
The advantages of steel bright bars we supply:
1) Big stocks of hot rolled round bars or wire rods as raw materials
2) Heat treating furnaces to adjust the mechanical properties
3) Full sets of testing equipment to test the sizes, mechanical properties and microstructure.
4) Multiple packages to avoid broken packages and anti-rusty
Diameter tolerance
+0/-0.02mm
Straightness
0.5mm/m
Surface roughness
0.4um
Roundness
80% of diameter tolerance
Diameter range
14mm to 100mm
Steel grade
Kinds of carbon steel and alloy steel
Length
Any length can be cut with precision tolerance
Bright Steel Bar Bright Flat Bar,Bright Steel Bar,C45 Steel Round Bar,Bright Steel Round Bar SHANDONG LE REN SPECIAL STEEL CO., LTD. , https://www.lerenspecialsteel.com
Typical diseases and control techniques of tomato in greenhouse
In recent years, due to the expansion of planting area, the greenhouse tomato has been difficult to rotate, some of the greenhouses are seriously damaged, and some farmers are not operating properly, resulting in aggravation of tomato diseases in greenhouses, and the quality and yield of tomato cultivation are declining. The symptoms and prevention methods are as follows:
1. Field symptoms: The lower leaves are wilting at the beginning of the disease, and gradually develop into the middle and upper leaves. At the base of the stem of the plant, the wet stain is visible near the ground, and a small amount of pale pink mold layer is formed on the surface. When the disease is serious, the whole plant leaves become yellow and withered, leading to death. The vascular bundle is browned when the diseased stem is cut.
2, prevention and treatment methods: prevention and control of blight can be used for green seedlings to disinfect the seedbed, with Green Heng No. 1 0.5 grams, 15 kg with soil, one-third of the seedling bed, two-thirds planted after the cover. It is also possible to use 70% dikesone WP of 5 grams per square meter, to treat the seedbed or root irrigation or 98% of the carbendazim 1 gram plus water 3 kg, spray on the soil. The initial onset is sprayed with 70% thiophanate-methyl 1000-fold solution or 80% carbendazim 600-fold solution. The medication interval is 7-10 days, and it is sprayed 2-3 times.
Second, late blight
1. Field symptoms: Large brown water-soaked plaques are produced at the tip or leaf edge of the leaf. When the humidity is high, there is a white mold layer at the edge of the lesion. The fruit appears as a large brown cloud-like lesion with irregular edges on the fruit surface. When the humidity is high, there is sparse white mold at the edge of the lesion. The diseased fruit is not soft at first, and softens and rots later. Late blight is an important disease in greenhouses, and it is easy to be popular in low temperature and rainy days.
2, prevention methods: (1) seed disinfection. Each kilogram of seed is seeded with Green Heng No. 2 and No. 3 4-5 grams. (2) Seedbed disinfection. Mix every square meter with Green Heng No. 2 and No. 3 4-5 grams with dry fine soil, spread evenly on the whole seedbed, and then water. The central diseased plants were found to be removed in time and controlled by the smoke method. Use chlorothalonil aerosol 1.5-1.8 grams per cubic meter for fumigation, and ventilate the next day. At the beginning of the disease, the following fungicides were sprayed: 72.2% of the spectrum, 40% of the bacteriophage, and 58% of the miRNAs. 7-10 days, even spray 4-5 times. After 10:00 am, take the medicine and ventilate after spraying.
1. Field symptoms: The middle and lower leaves are affected, and the leaves are gradually developed. In the early stage, white powder spots of different sizes are produced on the leaves, and gradually spread, so that the leaves are covered with white powder, and the white powder is removed to reveal the green tissue of the diseased part. In severe cases, the leaves are yellowish early and the plants are pulled.
2, prevention and treatment methods: before the onset or early onset with Luheng No. 2 800-1000 times liquid or 15%% triazolone wettable powder 1000 times liquid spray. Interval between 7 and 15 days.
1. Field symptoms: dark green water stain spots appear in the umbilical part of the fruit at the beginning of the disease, and then gradually expand to a diameter of 1-2 cm, or even half a fruit, the diseased tissue becomes brown to dark brown, then the dry rot shrinks, so that the umbilicus It has a flat or concave shape.
2, prevention and treatment methods: First, the selection of disease-resistant varieties. The varieties with smooth fruits and sharp fruits are more resistant to disease. The second is the top dressing. The tomato results in a key period of calcium absorption within one month. It can spray 1% of superphosphate and 1000-1500 times of calcium nitrate. 10-15 days once, even spray 2-3 times.
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