Galvanizatsiya va sherardlash

Sherdizing is also called thermal diffusion galvanizing (TDG), vapor galvanizing or  dry galvanizing, and it's is a specific process involving zinc powder and proprietary chemicals. Steel workpieces are cleaned before zinc coating process, and the cleaning process covers degrease and sandblasting, and then they are tumbled in a heated drum at temperatures slightly less than hot-dip galvanizing (680 - 825 degree F) so that matte gray HDG-like intermetallic alloy layers are produced.

VaholankiIssiq daldırma galvanizatsiyasi (HDG)is a process of handling steel workpieces to go through a series of pretreatment, and then dipping  steel parts into the molten (830 F) zinc bath with, and workpiece is lowered into the kettle at an angle which allows air to escape from tubular shapes or other corners. During the dipping process, the iron metallurgically reacts with the zinc to form a series of zinc-iron intermetallic layers and an outer layer of pure zinc.

What's the difference between sherardizing and HDG?

Issiq daldırma galvanizatsiya jarayoni vodorodning mo'rtlashishiga olib kelmaydi, lekin uni oldindan tozalash, kislotali tuzlash mo'rtlashuvga olib keladi. HDG odatda sherardlashdan ko'ra qo'polroq sirtga ega va sherardizatsiya odatda korroziyaga qarshi kuchli himoyani talab qiladigan qismlar uchun qo'llaniladi.Issiq daldırma galvanizli qismlar are widely used in infrastructure like motorway railing systems, cable racking system in tunnel and subway, solar energy, steel structure for bridge and construction. Sherardizing is widely used for fasteners and steel works which requires high precision assembly, and sherardizing production capacity is not as high as hot dip galvanizing because it's constrained by the tumbling drum.

Advantages of Sherardizing 

√  No risk of acid deposition around welded area

√  Complete elimination of hydrogen embrittlement

√  No need for re-threading or further fitting operations

√  Readily accepts top coats, no need for expensive primers

√  Withstand a fair measure of high industrial pollution and rough handling

√  Suitable for acting as a pre-coating for paints, powder coatings and rubber bonding

√  Hardest of all zinc coatings compared with hot dip galvanization, spin galvanization and zinc plating

√  Uniform coating, ideal for smaller and irregularly shaped items without unfavorable peak build up on 

    corners or on threads

√  Consists exclusively of intermetallic phase Fe-Zn, which permits the control of case depth and 

    ensures high corrosion resistance

√  Lower temperature process range, which avoids parts losing their mechanical properties and shapes 

    such as spring steels and fasteners

Sherdizatsiyaning foydasi tufayli, aniq yig'ishni talab qiladigan ko'plab po'lat mahsulotlar, shuningdek, korroziyaga qarshi mustahkam himoya{0}}shartlanadi, masalan, mahkamlagichlar,maxsus metall qavslar, po'lat konstruktsiya va po'lat shpallar.

Issiq daldırma galvanizatsiyasining kamchiliklari

√  Galvanizli suv quvurlari qo'rg'oshinni suv ta'minotiga chiqarishi mumkin

√  Rough coating surface, and spikes tend to remain at the end of workpiece during lifting process 

    which tekshirish vaqtida olib tashlanishi kerak

√  Due to the deposition of zinc, undercut nuts is required for fitting purpose, and the heat involved in 

    the galvanization process limits the grade of fastener

√  Due to its rough surface nature, it requires very strict control of sandblasting for uniform 

    galvanization surface.

Muxtasar qilib aytganda, issiq daldırma galvanizatsiyasining eng katta kamchiliklari uning tekis bo'lmagan yuzasi bo'lib, ayniqsa mahkamlagichlar uchun montaj muammolariga olib kelishi mumkin. Issiq daldırma galvanizatsiyasi dominant hisoblanadimetall yuzasiga ishlov berishuchuninfratuzilma, telekommunikatsiya, qishloq xo'jaligi, akvakultura, quyosh energiyasi, kon va tunnel.

Turli xil sink qoplamalari haqidagi asosiy faktlarni tasavvur qilish uchun siz narx, qoplama belgilari va tegishli standartlarni aniqroq tushunish uchun quyidagi jadvalga murojaat qilishingiz mumkin.