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Boot Covers

Universal Joint Boot Covers

Keeping universal joints fully lubricated reduces friction, wear and heat generation and can significantly prolong the useful life of the assembly. If pre-lubrication, such as in needle-bearing joints, or continuous lubrication with oil drips for example is not attainable, the joints can be fitted with lubricant-retaining boots (bellows).

In addition to maintaining component lubrication, boots can prevent contaminants entering and damaging the joints in environments polluted with chips, dirt, acids and/or other abrasives. 

Why Belden U Joint Boot Covers?

Standard u joint boots are typically manufactured from Nitrile. However, special operating environments might require other boot materials and lubricants. Some universal joint boot materials are more heat resistant than others. Extreme high and low temperatures can cause changes in the material’s composition as well as make the boots contract and expand past an acceptable range. Boots can also crack at low temperatures or swell if submerged in fuel or exposed to other harsh chemicals. Such issues can cause oils from the grease to seep through the silicone. For such operating conditions the development of alternative u joint boot materials or special design engineering solutions may be necessary, e.g. metal boot covers, bootless universal joints, dry-film lubrication, etc.
 

 U Joint Boot Material Information:

  • Nitrile (standard), also known as Buna-N, has excellent resistance to petroleum-based oils and fuels, silicone greases, hydraulic fluids, water and alcohol. It possesses high tensile strength and high abrasion resistance. Silicone boots are recommended for high temperature applications.
  • Silicone (-SL) is resistant to high, dry heat. It is also fungus resistant, odorless, tasteless and non-toxic. It has a high resistance to the aging effects of both sunlight and ozone.
  • Neoprene (-CR) was developed as an oil-resistant substitute for natural rubber. It features moderate resistance to petroleum oils and good resistance to ozone, sunlight, and oxygen aging. It has good resilience and is highly resistant to Freon® and Ammonia.
  • Viton (-VT) combines high temperature toughness with wide chemical agent compatibility. It features excellent resistance to petroleum products and solvents.
  • EPDM (-EPDM) has excellent ozone and chemical resistance. Effective resistance to steam up to 400 degrees Fahrenheit, hot water, silicone oils and greases, diluted acids and alkalis, alcohols and automotive break fluids.
Torque Values by Outside Diameter
Nominal OD (in) Max. Operating Torque Lb-in [N-m] Ultimate Torque Lb-in [N-m]
Matching Products
Part Number ØD1 (in) D2 (in) L1 (in) Bellows Material
1000 BOOT 1.00 1.50 1.50 Triple Nitrile
UJ-375 BOOT-SL 0.37 0.72 0.88 Double Silicone
1250 BOOT-VT 1.25 1.88 2.09 Triple Viton
UJ-2500 BOOT-SL 2.50 3.50 4.00 Triple Silicone
625 BOOT 0.62 1.13 1.03 Single Nitrile
UJ-750 BOOT 0.75 1.38 1.25 Single Nitrile
1000 BOOT-CR 1.00 1.50 1.50 Triple Neoprene
UJ-500 BOOT-SL 0.50 0.95 0.88 Double Silicone
1500 BOOT 1.50 2.25 2.06 Triple Nitrile
UJ-3000 BOOT-SL 3.00 4.25 4.63 Triple Silicone
625 BOOT-EPDM 0.62 1.13 1.03 Single EPDM
UJ-875 BOOT 0.87 1.50 1.50 Single Nitrile
1000 BOOT-EPDM 1.00 1.50 1.50 Triple EPDM
UJ-625 BOOT-SL 0.62 1.13 1.03 Single Silicone
1500 BOOT-SL 1.50 2.25 2.06 Triple Silicone
625 BOOT-SL 0.62 1.13 1.03 Single Silicone
UJ-1000 BOOT 1.00 1.50 1.50 Triple Nitrile
1000 BOOT-SL 1.00 1.50 1.50 Triple Silicone
UJ-750 BOOT-SL 0.75 1.38 1.25 Single Silicone
1750 BOOT 1.75 2.69 2.63 Triple Nitrile
625 BOOT-VT 0.62 1.13 1.03 Single Viton
UJ-1125 BOOT 1.12 1.75 1.63 Triple Nitrile
1000 BOOT-VT 1.00 1.50 1.50 Triple Viton
UJ-875 BOOT-SL 0.87 1.50 1.50 Single Silicone
1750 BOOT-SL 1.75 2.69 2.63 Triple Nitrile
750 BOOT 0.75 1.38 1.25 Single Nitrile
UJ-1250 BOOT 1.25 1.88 2.09 Triple Nitrile
1125 BOOT 1.12 1.75 1.63 Triple Nitrile
UJ-1000 BOOT-SL 1.00 1.50 1.50 Triple Silicone
2000 BOOT 2.00 2.69 3.00 Triple Nitrile
750 BOOT-EPDM 0.75 1.38 1.25 Single EPDM
UJ-1500 BOOT 1.50 2.25 2.06 Triple Nitrile
1125 BOOT-SL 1.12 1.75 1.63 Triple Silicone
UJ-1125 BOOT-SL 1.12 1.75 1.63 Triple Silicone
2500 BOOT 2.50 3.50 4.00 Triple Nitrile
750 BOOT-SL 0.75 1.38 1.25 Single Silicone
UJ-1750 BOOT 1.75 2.69 2.63 Triple Nitrile
1125 BOOT-VT 1.12 1.75 1.63 Triple Viton
UJ-1250 BOOT-SL 1.25 1.88 2.09 Triple Silicone
375 BOOT 0.37 0.72 0.88 Double Nitrile
3000 BOOT 3.00 4.25 4.63 Triple Nitrile
750 BOOT-VT 0.75 1.38 1.25 Single Viton
UJ-2000 BOOT 2.00 2.69 3.00 Triple Nitrile
1250 BOOT 1.25 1.88 2.09 Triple Nitrile
UJ-1500 BOOT-SL 1.50 2.25 2.06 Triple Silicone
375 BOOT-SL 0.37 0.72 0.88 Double Silicone
UJ-375 BOOT 0.37 0.72 0.88 Double Nitrile
875 BOOT 0.87 1.50 1.50 Single Nitrile
UJ-2500 BOOT 2.50 3.50 4.00 Triple Nitrile
1250 BOOT-EPDM 1.25 1.88 2.09 Triple EPDM
UJ-1750 BOOT-SL 1.75 2.69 2.63 Triple Silicone
500 BOOT 0.50 0.95 0.88 Double Nitrile
UJ-500 BOOT 0.50 0.95 0.88 Double Nitrile
875 BOOT-SL 0.87 1.50 1.50 Single Silicone
UJ-3000 BOOT 3.00 4.25 4.63 Triple Nitrile
1250 BOOT-SL 1.25 1.88 2.09 Triple Silicone
UJ-2000 BOOT-SL 2.00 2.69 3.00 Triple Silicone
500 BOOT-SL 0.50 0.95 0.88 Double Silicone
UJ-625 BOOT 0.62 1.13 1.03 Single Nitrile