Professional O-Ring and Oil Seal Manufacturer, Sealing Solution Supplier Since 2008.
Semi-finished Rubber Tube Stock for CNC Machining Custom Seals
- Material: Nitrile Butadiene Rubber (NBR / Buna-N)
- Hardness: Shore A 85
- Color: Black
- Structure: Solid vulcanized hollow tube
- Temperature: -30℃ ~ 100℃ continuous
- Processing Method: CNC turning, cutting, grinding
5.0
design customization
Please fill out the form below to request a quote or to request more information about us. Please be sure to upload customized requirement documents or pictures, and we will get back to you as soon as possible with a response. we're ready to start working on your new project, contact us now to get started.
Please fill out the form below to request a quote or to request more information about us. please be as detailed as possible in your message, and we will get back to you as soon as possible with a response. we're ready to start working on your new project, contact us now to get started.
NBR is the abbreviation of Nitrile Butadiene Rubber (also known as Buna-N), a copolymer of acrylonitrile and butadiene.
NBR semi-finished tube is pre-vulcanized hollow tubular semi-finished rubber material. Different from extruded raw uncured tube, this finished tube stock has completed vulcanization. Customers can directly conduct lathe turning, cutting and profiling to produce non-standard sealing components, which greatly shortens development cycle and avoids expensive custom mold investment.
Acrylonitrile (ACN) content dominates material performance: higher ACN brings better oil resistance, while lower ACN improves low-temperature flexibility.
1. Key Material Properties
General Performance
✅ Excellent resistance to petroleum-based oils, diesel, gasoline, lubricants, hydraulic oil and grease
✅ Good mechanical properties: tensile strength, abrasion resistance and compression set performance
✅ Wide adjustable hardness range: Shore A 50 ~ 90
✅ Good air tightness
✅ Easy machining, smooth surface after turning
✅ Good mechanical properties: tensile strength, abrasion resistance and compression set performance
✅ Wide adjustable hardness range: Shore A 50 ~ 90
✅ Good air tightness
✅ Easy machining, smooth surface after turning
Limitations
❌ Poor resistance to ozone, UV light and weather aging; avoid long-term outdoor exposure without protection
❌ Not resistant to strong polar solvents: ketones, esters, aromatic solvents, chlorinated solvents
❌ Low-temperature flexibility declines with higher acrylonitrile content
❌ Not resistant to strong polar solvents: ketones, esters, aromatic solvents, chlorinated solvents
❌ Low-temperature flexibility declines with higher acrylonitrile content
2. Manufacturing & Processing Information
- Raw NBR compound mixing → Extrusion into hollow tubular blank
- Continuous vulcanization / autoclave curing
- Dimension inspection, surface finishing
- Cutting into fixed-length semi-finished tubes for sale
Processing for Customers:
Our semi-finished NBR tube is fully vulcanized. End users only need CNC lathe turning to achieve required ID, OD, thickness and special profiles. No secondary vulcanization required.
Our semi-finished NBR tube is fully vulcanized. End users only need CNC lathe turning to achieve required ID, OD, thickness and special profiles. No secondary vulcanization required.
⚠️ Distinction important for communication:
- Uncured NBR tube: Raw extruded tube, needs further vulcanization
- Semi-finished NBR tube (machining stock): Pre-vulcanized, ready for machining
3. Typical Applications
- Automotive industry: oil seals, transmission seals, engine gaskets
- Hydraulic & pneumatic systems: cylinder seals, valve sealing elements
- Engineering machinery, construction equipment sealing parts
- Agricultural machinery, gearbox oil seal components
- General industrial equipment custom non-standard rubber seals
4. FAQ
Q1: Can you make custom ID & OD sizes of NBR semi-finished tube?
A: Yes. We support customized inner diameter, outer diameter and length. Please provide your required dimension and hardness.
Q2: What hardness options do you have for NBR tube stock?
A: Standard hardness: Shore A 60,70,80,85. Other hardness from 50~90 Shore A can be formulated.
Q3: Is this tube uncured? Do I need vulcanization after machining?
A: This is pre-vulcanized semi-finished tube. No secondary curing needed. You can machine directly.
Q4: Can this material be used outdoors exposed to sunlight?
A: NBR has weak UV and ozone resistance. Long-term outdoor exposure will cause cracking. We suggest adding anti-aging agent or choose HNBR/EPDM for outdoor working conditions.
Q5: What is the minimum order quantity?
A: Small trial orders are acceptable for regular sizes. MOQ depends on dimensions.
{{item.score}} Stars
{{item.pre}}%
{{item.nickname ? (item.nickname.slice(0, 2) + '*****') : item.source === 1 ? 'mall buyer' : '--'}}
{{item.comment_time}}
Review in the {{item.country}}
{{itemAttr.params_key}}: {{itemAttr.params_value}}
Get In Touch With Us
We are committed to meeting the diverse needs of our global customers through innovation and continuous improvement.
Need more information?
If you didn't find what you need, you can send an inquiry through our contact form.
Please fill in the form below.
Quick Links
Products
Contact Us