فنون

الجمال والعناية

حِرَف

الثقافة والتاريخ

ترفيه

البيئة

الطعام والمشروبات

الهندسة العكسية

العلوم

رياضة

التقنية

الأجهزة القابلة للارتداء

R. Henrik Nilsson (Wikimedia Commons) · CC BY 4.0

أنشأه

Martin

22. سبتمبر 2026

Nitrile Rubber (Buna-N)

At IG Farben in 1930 Erich Konrad and Eduard Tschunkur copolymerised butadiene with acrylonitrile. The nitrile group makes the chain polar, so oil and petrol - which are not - stay out. Sold as Buna N, nitrile rubber became the standard material for oil seals, fuel hoses and, much later, disposable gloves. **US 1,973,000**, "Rubber like masses from butadiene hydrocarbons and polymerizable nitriles", Konrad and Tschunkur, assigned to IG Farbenindustrie, filed 20. April 1931, granted 11. September 1934. It requires the butadiene to be more than about 60 % by weight of the mix. **You build the part nitrile made universal: an O-ring seal.** Turn two plugs with sized grooves, close a clear pipe with them, and leave it under water overnight.

متوسط

3 hours plus an overnight soak

التعليمات

The plug

One turned acetal plug: a flange that stops against the pipe end, a spigot that fits the bore, and a groove carrying the O-ring.

ملف التصميمBLENDCC0 - Free

تنزيل النموذج

Measure and choose

Cut 150 mm of clear PVC pipe and deburr both ends. Measure the bore at three angles and average. Pick a nitrile O-ring about 3 mm thick whose inside diameter is a little under bore minus 5 mm.

المواد لهذه الخطوة:

أنبوب PVC شفاف1 قطعة

طقم حلقات إحكام1 طقم

الأدوات المطلوبة:

منشار حديد

ورق صنفرة

قدمة رقمية 6 بوصات

Size the groove

جارٍ تحميل دفتر Jupyter…

Turn the spigot

Chuck acetal rod. Face it. Turn 12 mm of length to the bore minus 0.1 mm, leaving a 5 mm flange at full pipe outside diameter behind it.

المواد لهذه الخطوة:

قضيب دلرين/أسيتال1 قطعة

الأدوات المطلوبة:

مخرطة معادن

طقم أدوات المخرطة (HSS)

قدمة رقمية 6 بوصات

نظارة أمان شفافة

Cut the groove

3 mm from the spigot's end, plunge the parting tool to the root diameter from the notebook, then widen to 4.0 mm. Check the root with the caliper. Break the sharp edges.

الأدوات المطلوبة:

إزميل القطع للمخرطة

مخرطة معادن

قدمة رقمية 6 بوصات

Part off, make the second

Part off behind the flange. Make a second identical plug.

المواد لهذه الخطوة:

قضيب دلرين/أسيتال1 قطعة

الأدوات المطلوبة:

إزميل القطع للمخرطة

مخرطة معادن

Grease and fit

Wipe a thin film of petroleum jelly on each O-ring and roll it into its groove without twisting. Put a folded dry paper towel in the pipe and press both plugs home.

المواد لهذه الخطوة:

فازلين2 غ

منديل ورقي1 ورقة

Overnight under water

Weigh the capsule down in a bucket of water for 12 hours. Dry it outside, open it, and check the towel. Any damp spot shows which end leaked.

الأدوات المطلوبة:

دلو

History & Context

**What the patent specifies:** a butadiene hydrocarbon (over about 60 % by weight) polymerised with a polymerisable nitrile, by heating or in emulsion. **Modern build (derived):** commercial NBR O-rings in an acetal gland. Wartime Germany needed a rubber that fuel could not ruin, and nitrile answered it. More nitrile in the chain means more oil resistance and less flexibility in the cold. Its limits: ozone and sunlight crack it, and it swells in brake fluid and many solvents.