Evidenziare:
Robust hydraulic cylinder seal kit
, Construction dozer seal kit
, 7X-2689 hydraulic cylinder service kit
1. Quick Details of seal 7X-2689:
| Part NO. |
7X-2689 |
| Machine |
Crawler Dozers |
| Size |
OEM |
| Material |
NBR |
| Oil seal type |
SEAL KIT
|
2. 7X-2689 picture:

3. Service part number :
| PART NO. |
PART NO. |
Part NO. |
| 1714358 |
236-6919 |
9X7371 |
| 2263571 |
249-6670 |
3P0655 |
| 5W4819 |
3K-0360 |
195-2139 |
| 2353546 |
095-1716 |
8T-2306 |
| 2K2961 |
3K-0360 |
1P-7363 |
| 1411774 |
6V-9746 |
8T-2361 |
| 2R0098 |
3J-1907 |
7F-8607 |
| 6V5059 |
6V-8397 |
8F-0212 |
| 8C5176 |
3D-2824 |
2K8257 |
| 8C5175 |
5K-9090 |
1654854 |
| 9X-7680 |
210-0932 |
236-6919 |
| 109-1293 |
1M-9011 |
185-0303 |
4. FAQ
Q: Describe the natural color and surface texture of each component without any artificial dye or coating.
A: Low-temperature resistant NBR presents velvety black with fine grain and outstanding elasticity. Elastomer PU seals take on translucent light yellow and feature a compact, silky smooth surface. Mineral-filled PTFE rings are neutral gray with subtle mineral particle texture. Multi-filament woven guide rings show natural auburn brown, with neat and dense woven lines visible on the surface.
Q: What core performance does elastomer PU deliver inside the dozer hydraulic cylinders?
A: Elastomer PU combines excellent elasticity and dynamic wear resistance. As the dozer blade lifts, lowers and pushes soil continuously, it closely adheres to moving parts inside the cylinder. It firmly locks high-pressure hydraulic fluid inside the chamber and maintains stable sealing performance even under long-duration cyclic movement and irregular impact loads.
Q: What is the working mechanism of mineral-filled PTFE when matched with PU main seals?
A: Natural mineral fillers enhance the structural density and compression resistance of PTFE. It can fully fill the tiny assembly gaps within piston grooves. When the dozer pushes against dense soil or hard rock and triggers sudden hydraulic pressure surges, this material disperses instantaneous pressure evenly and protects the PU sealing lip from being squeezed, distorted or torn, greatly prolonging the service life of the whole sealing system.
Q: In what ways is low-temperature resistant NBR superior to conventional rubber materials?
A: Apart from reliable oil resistance and anti-aging properties, this customized NBR keeps good flexibility even in frigid environments. It will not harden, crack or lose sealing tightness when exposed to cold wind and frost. Meanwhile, it stays stable under prolonged hydraulic oil immersion and outdoor ultraviolet radiation, adapting to all-climate outdoor operations.
Q: Where are the NBR sealing components mainly installed on the hydraulic cylinder?
A: These rubber parts are mainly arranged on stationary connecting positions, including cylinder end covers, flange joints and threaded connectors of auxiliary hydraulic pipes. These areas are permanently exposed to hydraulic fluid and external natural environment, which can fully exert the comprehensive performance of low-temperature resistant NBR.
Q: What practical effects can multi-filament woven phenolic guide rings bring to the moving piston?
A: This woven guide ring can buffer the lateral deflection force generated by unbalanced pushing resistance during operation. It guides the piston to travel along the central axis steadily, prevents eccentric movement, and cuts down metal-to-metal friction between piston and cylinder bore. This effectively reduces component loss and keeps the cylinder running smoothly for a long time.
Q: Are all sealing parts manufactured in compliance with OEM original dimensional standards?
A: Every seal, backup ring and guide ring is strictly produced in accordance with original factory drawings and size specifications. Each component fits the standard installation grooves perfectly, so maintenance staff do not need to carry out any modification on the cylinder structure during replacement.
Q: Is trimming, stretching or other secondary processing required during on-site installation?
A: No extra processing is needed at all. After removing the worn and failed old seals, new components can be installed directly into the corresponding grooves. The matching tightness is pre-set reasonably, which simplifies installation steps and raises overall maintenance efficiency.
Q: Can customers purchase individual parts separately instead of the complete seal kit?
A: We mainly provide full kits for complete cylinder overhaul. If you only need to replace several damaged single parts due to partial failure, you can send us detailed specifications, and we will arrange separate supply according to your actual requirements.
Q: Can these materials adapt to dramatic temperature changes on outdoor construction sites?
A: Both mineral-filled PTFE and low-temperature resistant NBR have remarkable temperature adaptability. Their physical properties remain stable whether in freezing early mornings or scorching afternoons, ensuring consistent sealing performance throughout the day.
Q: Which component has the longest service life under harsh working conditions?
A: Mineral-filled PTFE backup ring possesses outstanding anti-abrasion and anti-extrusion capability. Under the combined influence of rock dust, gravel friction and frequent pressure changes on site, its service cycle is far longer than other sealing accessories.
Q: Are all materials compatible with standard hydraulic fluid for heavy dozers?
A: All raw materials have passed professional fluid compatibility tests. They will not swell, shrink or degrade after long-term contact with conventional anti-wear hydraulic oil, guaranteeing stable operation of the entire hydraulic system.
5. Exhibition and Wearhous



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