What Lubrication Tubing Does
Lubrication tubing carries oil or grease from the pump to metering elements and then to bearing points in a centralized lubrication system. It is the flexible connection that routes lubricant through machines while maintaining the pressure and flow needed for reliable delivery.
Bijur and Delimon are trademarks of their respective owners.
This is an aftermarket tubing supply, not manufactured, sponsored, or endorsed by Bijur Delimon.
Bijur Delimon part numbers are for cross-reference identification only.
Selecting the correct tube material and size affects system pressure, chemical compatibility, and installation life. The tubing must match the lubricant type, operating temperature, and mechanical demands of the machine.
Materials and Sizes
Bijur Delimon documents lubrication tubing in several materials. The table below lists documented sizes and published working pressures where available.
| Material | Documented sizes | Published working pressure |
| Nylon | 4, 6, 8, 10, 12 mm OD | 300 psi (21 bar) at 4 mm; 500 psi (35 bar) at 6 mm; 500 psi (35 bar) at 8 mm; 400 psi (28 bar) at 10 mm; 360 psi (25 bar) at 12 mm |
| Polyethylene | 4 mm OD x 2.5 mm ID; 6 mm OD x 4 mm ID | Not published in the cross-reference source |
| Polyurethane | 4 mm OD x 2.5 mm ID; 6 mm OD x 4 mm ID | Not published in the cross-reference source |
| Copper | Metric and inch sizes | Not published in the cross-reference source |
| Steel | Metric and inch sizes | Not published in the cross-reference source |
| Stainless steel | Metric and inch sizes | Not published in the cross-reference source |
Some 4 mm and 6 mm dimensions appear in both polyethylene and polyurethane documents with conflicting material descriptions. Confirm the exact material from the part number before ordering.
Pressure Ratings and Temperature
Published nylon working pressures apply at 20 °C only. Higher temperatures reduce the pressure capacity of plastic tubing, but no public derating curve exists for Bijur Delimon tubing.
Specialty high-pressure nylon items are documented, including a grease-filled UV high-pressure nylon listed at 1305 psi (90 bar). This is a separate product from standard nylon tubing and must be specified by part number.
For applications where grease pressure, pulsation, repeated flexing, or abrasion exceed a plastic tube rating, high-pressure hose assemblies are used instead. One documented example is hose of 4.1 x 8.75 mm retained by claw-groove studs.
Bend Radius, Length, and Installation
Bend radius is part-specific. There is no public bend-radius table for Bijur Delimon tubing, and the minimum bend must not be inferred from outside diameter alone.
Reel lengths such as 100 m are sales lengths, not permissible installed line lengths. The maximum installed length depends on pressure drop, lubricant viscosity, and system layout.
Plastic tubing assembled into compression fittings requires a tubing insert. Rigid metal tubing must not use a tubing insert.
One public Bijur document recommends 6 mm OD minimum for the single main feed line. Branch lines to individual points may use smaller diameters where pressure and flow allow.
Plastic Tubing or Steel Pipe
Plastic tubing is lighter, easier to route, and resists corrosion. It is common for branch lines and low-to-medium pressure circuits where flexibility simplifies installation.
Steel and stainless steel pipe suit high-pressure mains, hot environments, and areas with mechanical damage risk. Copper offers formability for small lines but has lower strength than steel.
The choice depends on pressure, temperature, lubricant type, and machine environment. Confirm the system requirements before substituting one material for another.
Related Parts
Plastic tubing in compression fittings needs tubing inserts to support the tube wall and prevent collapse.
Double-side compression sleeves seal tubing inside compression fittings for lubrication lines.
High-pressure hose assemblies use hose studs with claw-groove retention for secure attachment. For material and size selection help, use the quotation form.
Frequently Asked Questions
Which tube sizes exist for Bijur Delimon lubrication systems?
Common metric outside diameters are 4, 6, 8, and 10 mm. Nylon is also documented at 12 mm, with inch and specialty sizes available.
What pressure does nylon tubing hold per size?
At 20 °C, nylon holds 300 psi at 4 mm and 500 psi at 6 mm. It holds 500 psi at 8 mm, 400 psi at 10 mm, and 360 psi at 12 mm.
Should I choose nylon or polyethylene tubing?
Nylon offers higher published working pressures and better strength for most lubrication lines. Polyethylene is softer and may suit low-pressure or return-line use only.
When does polyurethane tubing make sense?
Polyurethane resists flexing and abrasion better than nylon in moving applications. Confirm the exact material from the part number because documents conflict for some sizes.
What bend radius applies to lubrication tubing?
Bend radius is part-specific and not published as a general table. Check the individual part datasheet before routing the tube.
How long may a lubrication line be?
Reel lengths such as 100 m are sales lengths, not installed line lengths. Maximum installed length depends on pressure drop, viscosity, and system layout.
Do plastic tubes need inserts in compression fittings?
Yes, plastic tubing assembled into compression fittings requires a tubing insert. Rigid metal tubing must not use a tubing insert.
Can I use plastic tubing outdoors in UV light?
No public UV-life statement exists for standard Bijur Delimon plastic tubing. A grease-filled UV high-pressure nylon is documented for outdoor exposure.
Should I use steel pipe or plastic at the pump outlet?
One public Bijur document recommends 6 mm OD minimum for the single main feed line. Steel pipe suits high-pressure mains, while plastic works for branch lines.
How do I order or get support?
IsoHiTech Lubrication Systems, founded in 2023, engineering since 2006, builds and supports every unit. Email inquiry@isohitech.com for specifications and a quotation.
Use the quotation form for a fast response. Include part numbers, quantities, and application details.
