????For steel/PTFE fabric spherical  plain bearing free of  maintenance,  there is a transfer of  PTFE from fabric to the sphere surface of the inner ring when in operation. Lubrication can generally interfere with the transfer, and shorten bearing life. Therefore，lubrication is not allowed for this kind of bearing.

????For steel/PTFE composite spherical  plain bearing,  lubrication is generally not  required.  But  when corrosion resistance and improving sealing is in need,  filling the surrounding space of  the bearing with lithium base grease is allowed.

????MoS2：Adding MoS2 contributes to the running-in of  bearing and the reducing of  wear during the running-in stage. MoS2 is treated with two kinds of way: wet-type and dry-type. Wet-type MoS2 is treated with dipping, and dry-type is treated with spray. The effect of dry-type MoS2 treating is superior to wet-type MoS2 treating. If customer need dry-type MoS2 treating, please contact with us when ordering.