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Lock nuts with locking washer or clip SKF lock nuts

Lock nuts with locking washer or clip SKF lock nuts with a locking washer or clip have four (fig 1) or eight (fig 2) equally spaced slots respectively, around the outside diameter to take a hook or impact spanner. The designations of the appropriate spanners are provided in the product tables.

The nut and the locking device must be ordered separately. The appropriate locking washer or clip is shown in the product tables.

KM(L) lock nuts with locking washer Lock nuts in the KM and KML series are available for metric ISO threads up to and including 200 mm and are locked with an MB(L) washer (fig 3) or with the stronger MB .. A design.

KML lock nuts have the same thread and width as the corresponding KM nuts with the same size code, but a smaller outside diameter.

HM(E) lock nuts with locking clip Lock nuts in the HM(E) 30 and HM 31 series with metric trapezoidal threads are locked by an MS locking clip consisting of the clip, a hexagon headed bolt to EN ISO 4017:2000 and a spring locking washer to DIN 128 (fig 4).

For easier handling, lock nuts from sizes HM 3168 resp. HM 3088 and above have a threaded hole in the outside diameter to fasten an eyebolt. The thread size is provided in the product tables.

N and AN lock nuts with inch dimensions Lock nuts with inch dimensions are available both in the light N 0(00) series and in the heavy N (00) and AN (00) series. Up to and including size 44 they are locked with W locking washers (fig 3). Larger nuts are locked with P locking plates (fig 5). N 0(00) lock nuts have the same thread and width as the corresponding N or AN nut with the same size code, but a smaller outside diameter.

Dimensions The dimensions and the thread of the metric nuts are in accordance with ISO 2982-2:2001. The dimensions of locking washers and locking clips also follow this standard.

Lock nuts with inch dimensions follow ANSI/ABMA Std. 8.2-1991.

  • KM(L) lock nuts with locking washer
  • HM(E) lock nuts with locking clip
  • N and AN lock nuts, inch dimensions
  • MB(L) locking washers
  • W locking washers, inch dimensions
  • MS locking clips
  • P locking plates, inch dimensions

Tolerances The metric ISO thread of KM and KML lock nuts is machined to tolerance 5H according to ISO 965-3:1998, and the metric trapezoidal thread of HM lock nuts to tolerance 7H, ISO 2903:1993.

Tolerances of inch dimension lock nuts are in accordance with ANSI/ABMA Std. 8.2-1991.

The maximum axial runout of the locating face with reference to the thread is between 0,04 and 0,06 mm for metric nuts and between 0,05 and 0,15 mm for inch dimensions nuts depending on the size of the lock nut.

Materials KM and KML lock nuts are made of spheroidal graphite cast iron or steel.

HM lock nuts up to and including size HM 3160 and HM 3064 respectively are made of spheroidal graphite cast iron. The larger nuts are made of steel.

N and AN inch dimension lock nuts are made of spheroidal cast iron, sintered steel or steel.

All SKF lock nuts are protected by a solventless rust inhibitor. The locking washers and locking clips and plates are made of deep drawn steel strip.

Mating shaft threads For the smaller metric lock nuts the mating thread on the shaft should be made to 6g according to ISO 965-3:1998 and to tolerance 7e according to ISO 2903:1993 for those with a trapezoidal thread.

For inch dimension lock nuts up to and including size 64 the mating thread on the shaft should be a UNS-3A thread according to ANSI/ASME B1.1-1989. Larger nuts need general-purpose Acme threads, class 3G according to ANSI/ASME B1.5.


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