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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
1750 BOOT-LP 1.75 2.00 3.50 none Nitrile
UJ-375 BOOT 0.38 0.72 0.88 Double Nitrile
375 BOOT 0.38 0.72 0.88 Double Nitrile
375_BOOT 0.38 0.72 0.88 Double Nitrile
375 BOOT-SL 0.38 0.72 0.88 Double Silicone
375_BOOT-SL 0.38 0.72 0.88 Double Silicone
UJ-500 BOOT 0.50 0.95 0.88 Double Nitrile
500 BOOT 0.50 0.95 0.88 Double Nitrile
500_BOOT 0.50 0.95 0.88 Double Nitrile
500 BOOT-SL 0.50 0.95 0.88 Double Silicone
500_BOOT-SL 0.50 0.95 0.88 Double Silicone
UJ-625 BOOT 0.63 1.13 1.03 Single Nitrile
625 BOOT 0.63 1.13 1.03 Single Nitrile
625_BOOT 0.63 1.13 1.03 Single Nitrile
625 BOOT-SL 0.63 1.13 1.03 Single Silicone
625_BOOT-SL 0.63 1.13 1.03 Single Silicone
625_BOOT-VT 0.63 1.13 1.03 Single Viton
625 BOOT-VT 0.63 1.13 1.03 Single Viton
625_BOOT-EPDM 0.63 1.13 1.03 Single Epdm
625 BOOT-EPDM 0.63 1.13 1.03 Single Epdm
750 BOOT 0.75 1.38 1.25 Single Nitrile
750_BOOT 0.75 1.38 1.25 Single Nitrile
UJ-750 BOOT 0.75 1.38 1.25 Single Nitrile
750_BOOT-SL 0.75 1.38 1.25 Single Silicone
750 BOOT-SL 0.75 1.38 1.25 Single Silicone
750_BOOT-VT 0.75 1.38 1.25 Single Viton
750 BOOT-VT 0.75 1.38 1.25 Single Viton
750_BOOT-EPDM 0.75 1.38 1.25 Single Epdm
750 BOOT-EPDM 0.75 1.38 1.25 Single Epdm
875_BOOT 0.88 1.50 1.38 Single Nitrile
875 BOOT 0.88 1.50 1.38 Single Nitrile
UJ-875 BOOT 0.88 1.50 1.38 Single Nitrile
875 BOOT-SL 0.88 1.50 1.38 Single Silicone
875_BOOT-SL 0.88 1.50 1.38 Single Silicone
UJ-1000 BOOT 1.00 1.50 1.50 Triple Nitrile
1000 BOOT 1.00 1.50 1.50 Triple Nitrile
1000_BOOT 1.00 1.50 1.50 Triple Nitrile
1000 BOOT-SL 1.00 1.50 1.50 Triple Silicone
1000_BOOT-SL 1.00 1.50 1.50 Triple Silicone
1000_BOOT-VT 1.00 1.50 1.50 Triple Viton
1000 BOOT-VT 1.00 1.50 1.50 Triple Viton
1000 BOOT-EPDM 1.00 1.50 1.50 Triple Epdm
1000_BOOT-EPDM 1.00 1.50 1.50 Triple Epdm
1000 BOOT-CR 1.00 1.50 1.50 Triple Neoprene
1000_BOOT-CR 1.00 1.50 1.50 Triple Neoprene
1125_BOOT 1.13 1.75 1.63 Triple Nitrile
UJ-1125 BOOT 1.13 1.75 1.63 Triple Nitrile
1125 BOOT 1.13 1.75 1.63 Triple Nitrile
1125_BOOT-SL 1.13 1.75 1.63 Triple Silicone
1125 BOOT-SL 1.13 1.75 1.63 Triple Silicone
1125 BOOT-VT 1.13 1.75 1.63 Triple Viton
1125_BOOT-VT 1.13 1.75 1.63 Triple Viton
UJ-1250 BOOT 1.25 1.88 2.09 Triple Nitrile
1250_BOOT 1.25 1.88 2.09 Triple Nitrile
1250 BOOT 1.25 1.88 2.09 Triple Nitrile
1250 BOOT-SL 1.25 1.88 2.09 Triple Silicone
1250_BOOT-SL 1.25 1.88 2.09 Triple Silicone
1250 BOOT-VT 1.25 1.88 2.09 Triple Viton
1250_BOOT-VT 1.25 1.88 2.09 Triple Viton
1250 BOOT-EPDM 1.25 1.88 2.09 Triple Epdm
1250_BOOT-EPDM 1.25 1.88 2.09 Triple Epdm
1250 BOOT-LP 1.25 1.50 2.00 none Nitrile
1250_BOOT-LP 1.25 1.50 2.00 none Nitrile
1500 BOOT 1.50 2.25 2.06 Triple Nitrile
UJ-1500 BOOT 1.50 2.25 2.06 Triple Nitrile
1500_BOOT 1.50 2.25 2.06 Triple Nitrile
1500_BOOT-SL 1.50 2.25 2.06 Triple Silicone
1500 BOOT-SL 1.50 2.25 2.06 Triple Silicone
1500_BOOT-LP 1.50 1.75 2.75 none Nitrile
1500 BOOT-LP 1.50 1.75 2.75 none Nitrile
1750_BOOT 1.75 2.50 2.63 Triple Nitrile
UJ-1750 BOOT 1.75 2.50 2.63 Triple Nitrile
1750 BOOT 1.75 2.50 2.63 Triple Nitrile
1750_BOOT-SL 1.75 2.50 2.63 Triple Silicone
1750 BOOT-SL 1.75 2.50 2.63 Triple Silicone
2000_BOOT 2.00 2.69 3.00 Triple Nitrile
UJ-2000 BOOT 2.00 2.69 3.00 Triple Nitrile
2000 BOOT 2.00 2.69 3.00 Triple Nitrile
2000_BOOT-SL 2.00 2.69 3.00 Triple Silicone
2000 BOOT-SL 2.00 2.69 3.00 Triple Silicone
2000 BOOT-LP 2.00 2.25 4.00 none Nitrile
2000_BOOT-LP 2.00 2.25 4.00 none Nitrile
2500 BOOT 2.50 3.50 4.00 Triple Nitrile
2500_BOOT 2.50 3.50 4.00 Triple Nitrile
UJ-2500 BOOT 2.50 3.50 4.00 Triple Nitrile
2500 BOOT-SL 2.50 3.50 4.00 Triple Silicone
2500_BOOT-SL 2.50 3.50 4.00 Triple Silicone
2500 BOOT-LP 2.50 2.75 4.63 none Nitrile
2500_BOOT-LP 2.50 2.75 4.63 none Nitrile
3000_BOOT 3.00 4.25 4.63 Quadruple Nitrile
3000 BOOT 3.00 4.25 4.63 Quadruple Nitrile
UJ-3000 BOOT 3.00 4.25 4.63 Quadruple Nitrile
3000_BOOT-SL 3.00 4.25 4.63 Quadruple Silicone
3000 BOOT-SL 3.00 4.25 4.63 Quadruple Silicone
3000_BOOT-LP 3.00 3.25 5.50 none Nitrile
3000 BOOT-LP 3.00 3.25 5.50 none Nitrile