5.4.3 Use in Abrasive Conditions
Strong abrasive materials, such as sand, coke, metal particles, or substantial amounts of dust in the air may affect the wear life of a chain. The particles may get into the chain's working parts and engaging parts between the chain and the sprockets. In this case, you can take these steps:
- Select a chain with hardened working parts. The parts need to be harder than the foreign objects.
- Reduce the bearing pressure by using a larger-sized chain. This increases the abrasion-wear area.
If you're operating conveyor chains in abrasive conditions, consider the following points:
- Select a chain with thicker bushings to increase the abrasion-wear area.
- Design the system so that the plates slide on the rails rather than roll on them. The bottom edge of the plate may accept much more abrasion wear than the area between the bushings and the rollers.
- Install many small rollers in the equipment, instead of rails. This is especially useful when conveying objects that cause significant wear.
In addition to causing wear, some objects may get into the working clearances of the chain, making it difficult or impossible for the chain to bend or rotate. In such cases, take the following steps:
- Use seals, such as oil seal, labyrinth seal, or O-ring seals, to prevent particles from getting into the chain. (Applicable size is limited.)
- Install a grease nipple and grease the chain regularly. Grease will force the particles from the chain. (Applicable size is limited.)
- Increase the clearances so that particles will fall out, even if they get into the chain. This is the most common method.
| Corrosive Agent | Conc. | Temp. (°C) | Anti-corrosive Chain | Sprockets | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| SS | AS | CS | NS | TI | PC | PC•SY | Engineered Plastic |
304SS | |||
| Acetone | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 4 | 1 | 1 | |
| Oil (Vegetable, Mineral) | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |
| Linseed Oil | 20 | 1 | 2 | 2 | 1 | 1 | 1 | 3 | 1 | 1 | |
| Sulfurous Acid Gas | 100% | 20 | 1 | 4 | 4 | 1 | 1 | 3 | 3 | 3 | 1 |
| Alcohol | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |
| Ammonia (Aqueous | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |
| Whiskey | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |
| Ethyl Ether | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |
| Zinc Chloride | 50% | 20 | 2 | 4 | 4 | 2 | 1 | 2 | 1 | 4 | 2 |
| Ammonium Chloride | 50% | Boiling | 2 | 4 | 4 | 1 | 1 | 3 | 3 | 3 | 2 |
| Potassium Chloride | Saturated | 20 | 1 | 2 | 2 | 1 | 1 | 3 | 3 | 1 | 1 |
| Calcium Chloride | Saturated | 20 | 2 | 4 | 4 | 1 | 1 | 2 | 1 | 1 | 2 |
| Ferric Chloride | 5% | 20 | 2 | 4 | 4 | 2 | 1 | 3 | 3 | 4 | 2 |
| Sodium Chloride | 5% | 20 | 1 | 2 | 2 | 1 | 1 | 1 | 1 | 1 | 1 |
| Hydrochloric Acid | 2% | 20 | 4 | 4 | 4 | 4 | 1 | 4 | 1 | 4 | 4 |
| Chlorine Gas (Dry) | 20 | 2 | 4 | 4 | 2 | 1 | 3 | 1 | 4 | 2 | |
| Chlorine Gas (Wet) | 20 | 4 | 4 | 4 | 2 | 1 | 3 | 1 | 4 | 4 | |
| Chlorine Water | 20 | 4 | 4 | 4 | 1 | 1 | 4 | 3 | 4 | 4 | |
| Oleic Acid | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 3 | 1 | 1 | |
| Sea Water | 20 | 2 | 4 | 4 | 1 | 1 | 2 | 1 | 1 | 2 | |
| Sodium Perchlorate | 10% | Boiling | 1 | 4 | 4 | 1 | 1 | 3 | 3 | 3 | 1 |
| Sodium Peroxide | 30% | 20 | 1 | 2 | 2 | 1 | 1 | 4 | 1 | 4 | 1 |
| Gasoline | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |
| Potassium Nitrate | 25% | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 3 | 1 | 1 |
| Potassium Nitrate | 25% | Boiling | 1 | 4 | 4 | 1 | 1 | 3 | 3 | 3 | 1 |
| Vinegar | 20 | 2 | 4 | 4 | 1 | 1 | 2 | 1 | 2 | 2 | |
| Potassium Hydroxide | 20% | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Calcium Hydroxide | 20% | Boiling | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 3 | 1 |
| Sodium Hydroxide | 25% | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Stearic Acid | 100% | Boiling | 4 | 4 | 4 | 1 | 1 | 4 | 3 | 1 | 4 |
| Beverage | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | ||
| Carbolic Acid | 20 | 1 | 1 | 1 | 1 | 1 | 4 | 1 | 4 | 1 | |
| Petroleum | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 3 | 1 | 1 | |
| Water (Soapy) | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |
| Soda Water | 1 | 1 | 1 | 1 | 1 | 3 | 3 | 3 | 1 | ||
| Sodium Hydrogen | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 3 | 1 | 1 | |
| Sodium Carbonate | Saturated | Boiling | 1 | 1 | 1 | 1 | 1 | 3 | 1 | 2 | 1 |
| Sodium Thiosulfate | 25% | Boiling | 1 | 1 | 1 | 1 | 1 | 3 | 3 | 3 | 1 |
| Turpentine | 35 | 1 | 1 | 1 | 1 | 1 | 3 | 3 | 3 | 1 | |
| Kerosene | 20 | 1 | 1 | 1 | 1 | 1 | 3 | 1 | 3 | 1 | |
| Varnish | 1 | 1 | 1 | 1 | 1 | 3 | 3 | 3 | 1 | ||
| Nitric Acid | 65% | 20 | 1 | 4 | 4 | 1 | 1 | 4 | 1 | 4 | 1 |
| Nitric Acid | 65% | Boiling | 2 | 4 | 4 | 2 | 1 | 4 | 4 | 4 | 2 |
| Lactic Acid | 10% | 20 | 1 | 2 | 2 | 1 | 1 | 1 | 3 | 1 | 1 |
| Honey | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | ||
| Paraffin | 20 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |
1 = High corrosion
2 = Partial corrosion resistance
3 = Unknown
4 = Not resistant
Bearing roller chain and bearing bush chain contain rotating elements, so they are very sensitive to particulate contamination. Make sure you install fixed seals when operating either of these.
