Environmentally protected tubing and method of making it
A highly corrosion and abrasion resistant coating combination for high precision metal tubing comprises a passivation layer applied to the tubing and a thermoplastic jacket extruded onto the passivated tubing.
1. A method of forming environmentally protected tubing comprising applying an extruded thermoplastic coating over tubing having a passivation layer thereon, the thermoplastic coating forming a friction fit with the tubing without bonding to the tubing.
2. The method of claim 1 wherein the passivation layer comprises a silicon layer on the tubing.
3. The method of claim 1 wherein the tubing is formed of stainless steel.
4. A method of forming environmentally protected tubing comprising applying an extruded thermoplastic coating over tubing having a passivation layer thereon, wherein the passivation layer comprises a silicon layer on the tubing, wherein the tubing is formed of stainless steel, and wherein the tubing is coiled and thereafter passivated.
5. The method of claim 1 comprising a step of applying the passivation layer using a vapor deposition method.
6. A method of forming environmentally protected tubing comprising applying an extruded thermoplastic coating over tubing having a passivation layer thereon, and comprising a further step of coiling the tubing on a spool having helical grooves which prevent tubing wraps from contacting each other.
7. The method of claim 6 wherein the spool is made of a non-metallic material.
8. The method of claim 1 wherein the tubing is passivated with a substance selected from the group consisting of silicon, zinc, and ceramic.
9. A method of forming environmentally protected tubing comprising applying an extruded thermoplastic coating over tubing having a passivation layer thereon, and further comprising bundling the tube with at least one other tube, and applying a thermoplastic wrap around the tubes.
10. Environmentally protected tubing comprising a metal tube, a passivation layer on the tube, and a thermoplastic layer applied to the passivation layer, the thermoplastic coating forming a friction fit with the tubing without bonding to the tubing.
11. The tubing of claim 10 wherein the passivation layer is a silicon passivation layer.
12. Environmentally protected tubing comprising a metal tube, a passivation layer on the tube, and a thermoplastic layer applied to the passivation layer, wherein the tube is bundled with at least one other tube, the bundled tubes having a wrap of thermoplastic material around them.
13. The tubing of claim 12 wherein the bundled tubing is surrounded by a non-hygroscopic insulation material.
14. The tubing of claim 13 wherein the insulation material comprises a closed cell foam insulation.
15. The method of claim 1 further comprising bundling the tube with at least one other tube, and applying a thermoplastic wrap around the tubes.
16. The tubing of claim 10 wherein the tube is bundled with at least one other tube, the bundled tubes having a wrap of thermoplastic material around them.