ISO VG (Viscosity Grade) is a classification system for industrial lubricants defined by ISO 3448. Each grade corresponds to a kinematic viscosity midpoint at 40°C in centistokes (cSt). For example, VG 46 means the oil has a midpoint viscosity of 46 cSt at 40°C, with an allowed range of 41.4–50.6 cSt (±10%).

To'g'ri yopishqoqlik sinfini qanday tanlash kerak?

Tanlov qo'llanilishiga bog'liq: gidravlik tizimlar uchun VG 32–46, sanoat reduktorlari uchun VG 68–150, og'ir yuklangan yopiq tishli uzatmalar uchun VG 220–460, yuqori tezlikli shpindellar uchun VG 10–22. Doimo uskunа ishlab chiqaruvchisining tavsiyalariga rioya qiling.

ISO VG va SAE o'rtasidagi farq nima?

ISO VG grades are based on kinematic viscosity at 40°C and are used for industrial lubricants. SAE grades are used for automotive oils: SAE crankcase grades (e.g. 10W-30) are measured at 100°C, while SAE gear grades (e.g. 75W-90) use a different viscosity range. The two systems do not directly correspond.

Harorat yopishqoqlikka qanday ta'sir qiladi?

Harorat oshgani sayin moy yopishqoqligi pasayadi. ISO VG tizimi 40°C dagi yopishqoqlikni belgilaydi. Haroratga bog'liq o'zgarish tezligi Yopishqoqlik Indeksi (VI) bilan tavsiflanadi. Yuqori VI qiymati harorat o'zgarishi bilan yopishqoqlikning kamroq o'zgarishini bildiradi. Odatiy mineral moylar VI 80–100 ga ega; sintetik moylar VI 150+ ga yetishi mumkin.

cSt stands for centistokes (mm²/s), the unit of kinematic viscosity. It measures how fast a fluid flows under gravity. 1 cSt = 1 mm²/s. Dynamic viscosity in cP (centipoise) = kinematic viscosity in cSt × density in g/cm³.

Muhandislik uchun bepul vosita

Moy yopishqoqligi sinflari — ISO VG

ISO 3448 bo'yicha ISO VG yopishqoqlik sinfini aniqlang. Mos sinfni topish uchun 40 °C dagi kinematik yopishqoqlikni kiriting yoki yopishqoqlik diapazoni va odatiy qo'llanilishini ko'rish uchun VG sinfini tanlang.

ISO 3448 VG 2 – VG 1500 cSt @ 40 °C

40 °C dagi yopishqoqlik (cSt = mm²/s)

Yoki ISO VG sinfini tanlang

Quick presets

Results

ISO VG Class

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Yopishqoqlik diapazoni (min – max)

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O'rtacha yopishqoqlik

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Odatiy qo'llanilishi

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ISO 3448 yopishqoqlik tasnifi

ISO 3448 defines 18 viscosity grades for industrial lubricants. Each grade is identified by a number equal to the nominal kinematic viscosity midpoint at 40 °C in centistokes (cSt). The allowed range is ±10% of the midpoint.

Range = Midpoint × 0.9 to Midpoint × 1.1 [cSt at 40 °C]

To'liq ISO VG jadvali

ISO VG	Min (cSt)	Midpoint (cSt)	Max (cSt)	Odatiy qo'llanilishi

Qo'llanilish bo'yicha qo'llanma

Application	Tavsiya etilgan ISO VG
Yuqori tezlikli shpindellar	VG 10 – VG 22
Gidravlik tizimlar	VG 32 – VG 46
Sanoat mashinalari uchun umumiy moylashtirish	VG 46 – VG 68
Sanoat reduktorlari	VG 68 – VG 150
Og'ir yuk uchun yopiq tishli uzatmalar	VG 220 – VG 460
Juda og'ir yuk / sekin aylanadigan tishli uzatmalar	VG 680 – VG 1500

Note: ISO VG darajalari yopishqoqlikni faqat 40 °C da belgilaydi. Haqiqiy ish yopishqoqligi xizmat davomidagi moy haroratiga bog'liq. Boshqa haroratlardagi yopishqoqlikni baholash uchun Yopishqoqlik Indeksidan (VI) foydalaning.