Nickel is an element of Group VIII of the Periodic Table of the Elements. Its position in the periodic table determines a series of physicochemical properties of nickel and its compounds. Many physicochemical properties of nickel are similar to those of dangerous cobalt and iron ; The table is adjacent to copper and is therefore closer to copper in terms of oxophilic and thiophilic properties.
(A) Main physical and chemical properties of nickel Nickel is a silvery white metal, the density at 20 ℃ of 8.908g.cm -3, melting point (1453 deg.] C) Liquid density nickel 7.9g · cm -3 , 1500 ° C is 7.76g · cm -3 , the density of other nickel products (g.cm -3 ) are: cast nickel 8.8, electric nickel 8.9, nickel shot 8.4, chemically pure nickel 9.04 ± 0.03.
The specific resistance of nickel at 20 ° C is 6.9 × 10 -6 Ω / cm. Although nickel-based alloys are widely used in thermal elements, pure nickel is practically not used for reasons of easy oxidation. The thermoelectricity is different from iron, copper, silver, and metal, and is lower than platinum . Therefore, the current at the cold end flows from platinum to nickel. Therefore, when nickel is used as the thermoelectric element, a high electric steel production momentum can be generated. At room temperature, industrial nickel has a maximum saturation polarization of 0.61T and a minimum coercivity of 1.5A/cm. It is a magnetic material (from a high magnetic permeability soft magnetic alloy to a high coercivity, which determines the working of nickel magnetic devices). Upper limit temperature.
A unit volume of nickel can absorb 4.15 times the volume of hydrogen.
Nickel has an atomic number of 28, an atomic weight of 58.71, a melting point of (1453 ± 1) ° C, and a boiling point of 2732 ° C. Nickel is not easily rusted in the atmosphere and is resistant to caustic alkalinity. Atmospheric experiments show that 99% pure nickel does not rust in 20 years, and the ability of nickel to resist caustic in aqueous solution or dissolved salt is strong; the annual etch rate of boiling 50% caustic soda solution does not exceed 25μm For salt solutions, it is only susceptible to attack by oxidizing salts such as oxidized high iron or iron hypochlorite. In air or oxygen, the electrode position of nickel is -0.227V, and it is -0.231V at 25°C. If there is a small amount of impurities in the solution, especially in the presence of sulfur, nickel is significantly passivated.
(B) a compound of the main properties of the nickel compound and a nickel There are three basic forms in nature, i.e., nickel oxides, sulphides and arsenic compounds. Its oxides are nickel oxide (NiO) and nickel tetraoxide (Ni 2 O 3 ). Nickel oxide is stable only at low temperatures, heated to 400-450 ° C, that is, dissociated into nickel oxynitride, and further increased in temperature to eventually become nickel oxide. Nickel can form a variety of salts, but unlike cobalt, only two-valent nickel salts are formed. Therefore, unstable nickel oxynitride is often used as an oxidant for more negatively charged metals (such as C0, Fe) for nickel electrolyte purification. Except C0. Nickel oxide has a melting point of 1650-1660 ° C and is easily reduced by C or CO. Nickel oxide, like CoO and FeO, can form a two-type silicate compound of NiO·SiO 2 of 2NiO·Si 2 , but NiO·SiO 2 is unstable. Nickel oxide has a catalytic action, which can convert SO 2 into SO 3 , and SO 3 and NiO can form stable sulfate, and it is stable compared with copper and iron sulfate, and is dissociated significantly when heated to 750-800 ° C. Nickel oxide can be dissolved in a solution of sulfuric acid, sulfurous acid, hydrochloric acid and nitric acid to form a green divalent nickel salt. When reacted with lime milk, green nickel hydroxide [Ni(OH) 2 ] is precipitated.
Nickel sulfides include NiS 2 , Ni 6 S 5 , Ni 3 S 2 , NiS, and the like. Nickel sulfide (NiS) is unstable at high temperatures and is dissociated as follows when heated under neutral and reducing atmospheres:
3NiS=Ni 3 S 2 +1/2S 2
At the smelting temperature, low nickel sulfide (Ni 3 S 2 ) is stable, and its decompression pressure is smaller than FeS, but larger than Cu 2 S.
The arsenic of nickel is nickel arsenide (NiAs) and nickel arsenide (Ni 3 As 2 ). The former is a red arsenic-nickel ore in nature, and can be dissociated in neutral oxygen:
3NiAs=Ni 3 As 2 +As
In the oxidizing atmosphere, a part of arsenic of the red arsenic nickel ore forms volatile As 2 O 3 , and a part forms a volatile arsenate (NiO·As 2 O 3 ). Therefore, in order to more completely remove arsenic, after oxidative calcination, it is necessary to carry out reduction roasting to convert arsenate into arsenide, and further oxidize roasting to cause arsenic to be volatilized in As 2 O 3 form, that is, to perform alternate redox Calcination to complete the arsenic removal process.
Nickel is similar to iron and cobalt, and can form nickel carbonyl [Ni(CO) 4 ] with carbon monoxide under normal pressure conditions and at a temperature of 40-100 ° C:
Ni+4CO=Ni(CO) 4 +163.6kJ
When the temperature is raised to 150-316 ° C, the nickel carbonyl is decomposed into metallic nickel. This reaction is the theoretical basis for the nickel extraction by carbonyl.
Needle Assembly Machine:
Needle assembly machine is only one kind of needle manufacturing machines. We offer many different automatic needle assembly machines. The main one is hypodermic needle assembly machine. It is used to assemble ready needle cannula, needle hub and needle cap to be a finished needle. This process is fully automatic.
Besides, other needle assembly machines like safety needle assembly machine, blood collection needle assembly machine, Novo pen needle assembly machine etc are also offered.
Technical Parameter:
Name: Fully Automatic Hypodermic Needle Assembly Machine
Operation of worker: 1 operator
Dimension: 7000*3400*1600mm
Capacity: 45000 pieces per hour ( for master )
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1. Are you a manufacturer?
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2. Can you provide the oversea service?
Yes, after the machines arrive at your factory, we will arrange engineers go to install the machine and train your operators.
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1 year warranty ( failure caused by machine quality ) from the equipment arrive at the client`s factory. Lifetime maintenance and offer for the spare parts.
Needle Assembly Machine
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