BOSCH REXROTH
R167121420

$389.59

BOSCH REXROTH
Material:R167121420

Quantity in stock: 8

Ball runner block, BNS, size 25, steel CS, accuracy standard, low preload, without ball chain

The ball runner block is highly precise and characterized by the following product features:
Size 25
Format BNS: Width = wide, length = normal, height = standard
Runner block body made of unalloyed steel CS
Preload class C1: Low preload
Accuracy class N: Standard
Without ball chain
With initial lubrication and preservation
Roller bearing grease Dynalub 510
Without attachment element, left (front reference edge)
Without attachment element, right (front reference edge)
Straight lube connection loosely attached.
Runner block body in standard version
Overall length of the runner block = 105.0 mm
Interchangeability: The runner block and the guide rails can be combined with each other with every accuracy.

Unpacked Weight: 1.331 kg

Product description of Ball Rail Systems

Production description – Ball Runner Block

Materials

Selection of a linear guide acc. to DIN 637

Ball chain and seals

Design and version

Friction

technical illustration-r167121420-Ball runner block, BNS, size 25, steel CS, accuracy standard, low preload, without ball chain

Due to the Rexroth design with four rows of balls, 2-point contact is available in all loading directions. This reduces the friction to a minimum.

Other ball rail systems with two or four rows of balls with 4-point contact have multiple friction: due to the differential slip with lateral loading and in case of comparable prestressing without the load, the gothic raceway profile causes higher friction (depending on the raceway curvature and the load, up to five times the friction coefficient). This high friction leads correspondingly to greater heat.

Seals

Seals are use to prevent dirt, chips and coolants, etc. from working their way into the inside of he Ball Runner Block, thereby preventing reductions to its service life. For further information, see "Selection criteria/seals".

Standard seal (SS)

Universal seals are fitted as standard in Rexroth Ball Runner Blocks. They have a uniform sealing effect for Ball Guide Rails with and without cover strips. Low friction and a good sealing effect have both been taken into account in the design. For applications where effective sealing is required.

Low-friction seal (LS)

For special requirements with regard to ease of movement.

Double-lip seal (DS)

For increased exposure to media

Front seal

For applications in environments with fine dirt or metal particles, as well as coolants or cutting fluids.

Interchangeable during servicing.

Front seals are available as accessories for mounting by the customer.

FKM seal

For applications in extreme environments with fine dirt or metal particles, as well as heavy use of coolants or cutting fluids.

Interchangeable during servicing.

FKM front seals are available as accessories for mounting by the customer.

Cover plate wiper

For use in environments with coarse dirt or chips.

Cover plate wiper are available as accessories for mounting by the customer.

Attention! Size 20/40:

New Ball Rail Systems with different ball diameters. Not interchangeable with the old 20/40 size!

Area of application: For high torsional moments on rails
The same high load ratings in all four main directions of loading
Long-term lubrication is possible over several years
Excellent dynamic characteristics: Excellent dynamic characteristics
Attachments on the ball runner block can be mounted from above and below
High torque load capacity
Integrated all-round sealing
Improved rigidity under lift-off and side loading conditions due to two additional mounting screw holes at the center of the ball runner block
Can be used on all BNS ball guide rails
Wide range of accessories
End-face fastening thread for all attachments
Lube connection with metal thread on all sides
Optimized entry-zone geometry and high number of balls minimize variation in elastic deflection
Maximum system rigidity due to preloaded O-arrangement
Very high torsional moment load capacity and very high torsion resistance – therefore primarily used as an individual guide
Ball runner block pre-lubricated at the factory

Data Sheet	Download Data Sheet
3D CAD	Download 3D CAD
3D CAD	Download 3D CAD
Manual	Download Manual
Manual	Download Manual
Manual	Download Manual
Manual	Download Manual

Height of runner block	29.75
Footnote permissible ambient temperature (min ... max)	100 °C admissible for short time. For operation at negative temperatures, please consult us.
Footnote dynamic load capacity C	Determination of the dynamic load capacities and load moments is based on a 100 000 m travel as per DIN ISO 14728-1. Often only 50 000 m are actually stipulated. For comparison: Multiply values C, Mt and ML from the table by 1.26.
Size E2 (profiled rail systems)	60
Footnote friction coefficient μ	Without friction of seal
Permissible ambient temperature	-10 °C ... +80 °C
Format	BNS - wide, normal, standard height
Self-aligning for compensation of misalignments	Without self-alignment
Ball chain	Without ball chain (standard)
Friction coefficient μ	0,002 ... 0,003
Pitch T guide rail	80
Height of runner block with guide rail	35
Static load rating C0	50200
Dynamic torsional moment load capacity Mt	1350
Preload class	C1 - Low preload
Size B1 (profiled rail systems)	76.5
Size H (profiled rail system)	35
Friction coefficient μ min.	0.002
Accuracy class	N - normal
Size K4 (profiled rail systems)	5.2
Size B with tolerance (profiled rail systems)	105 mm
Size H2 (profiled rail systems)	23.55
Size K3 (profiled rail systems)	5.2
Size A1 (profiled rail systems)	60
Static torsional moment load capacity Mt0	1870
Runner block or guide rail	Runner block
Width of runner block	120
Size E8.1 (profiled rail systems)	83.5
Size E8 (profiled rail systems)	35
Length of runner block	105
Size E9.1 (profiled rail systems)	11.3
Linear guide type	Ball rail system
Dynamic load capacity C	36200
Static longitudinal moment load capacity ML0	680
Size E9 (profiled rail systems)	4.9
Size N1 (profiled rail systems)	9.35
Size E1 (profiled rail systems)	107
Material (profiled rail systems)	Carbon steel
Size N6 with tolerance (profiled rail systems)	14,4 mm ±0,5
Size S5 (profiled rail system)	7
Max. acceleration amax	500
Size A (profiled rail systems)	120
Size N6 tolerance (profiled rail systems)	±0.5
Size A3 (profiled rail systems)	25.5
Preload force	580
Size A2 (profiled rail systems)	69
Maximum permissible linear speed vmax	5
Lubrication	With initial lubrication and preservation
Size S1 (profiled rail systems)	6.7
Size N2 (profiled rail systems)	7.05
Size N6 (profiled rail systems)	14.4
Friction coefficient μ max.	0.003
Size B (profiled rail systems)	105
Seal	SS – Standard seal
Size K2 (profiled rail systems)	15.5
Size V1	7.5
Productgroup ID	17
Size K1 (profiled rail systems)	15.4
Dynamic longitudinal moment load capacity ML footnote	Determination of the dynamic load capacities and load moments is based on a 100 000 m travel as per DIN ISO 14728-1. Often only 50 000 m are actually stipulated. For comparison: Multiply values C, Mt and ML from the table by 1.26.
Permissible ambient temperature (max)	+80
Size S9 thread diameter x lead with tolerance (profiled rail systems)	M3x2 mm +4,5
Size S9 thread diameter x lead with tolerance (profiled rail systems)	+4.5
Dynamic longitudinal moment load capacity ML	490
Size S2 (profiled rail systems)	M8
Permissible ambient temperature (min)	-10
Note: Max. acceleration amax	If F_comb◡> 2.8 • F_pr : a_max = 50 m/s²
Size T1 min (profiled rail systems)	10
Dynamic torsional moment load capacity Mt footnote	Determination of the dynamic load capacities and load moments is based on a 100 000 m travel as per DIN ISO 14728-1. Often only 50 000 m are actually stipulated. For comparison: Multiply values C, Mt and ML from the table by 1.26.
Size S9 thread diameter x lead with (profiled rail systems)	M3x2
Internal product information	For LS – low-friction seal with external longitudinal seal
Weight	1.331
Nominal size	25/70
Size H1 (profiled rail systems)	29.75

Load capacities and load moments

Size		20/40 1)	25/70
C	N	14900	36200
C0	N	20600	50200
Mt	Nm	340	1350
Mt0	Nm	470	1870
ML	Nm	140	490
ML0	Nm	190	680

1)	Attention: Ball Runner Blocks, not combinable with Ball Guide Rail R167. 8.. .. !
	The calculation of the dynamic load ratings and load moments is based on a stroke length of 100,000 m as per DIN ISO 14728-1. However, often only 50,000 m is actually stipulated. For comparison: Multiply the values C,Mt and ML from the table by 1.26.

General technical data

Size		20/40 1)	25/70
amax 2)	m/s²	500
vmax	m/s	5
m	kg	0.4	1.2
μ 3)		0.002 ... 0.003
Operating conditions
Size		20/40 1)	25/70
Permissible ambient temperature (min ... max) 4)		-10 °C ... +80 °C

1)	Attention: Ball Runner Blocks, not combinable with Ball Guide Rail R167. 8.. .. !
2)	If Fcomb > 2.8 • Fpr : amax = 50 m/s2
3)	Without friction of seal
4)	Up to 100 °C permissible for short periods. For operation at negative temperatures, please consult us.

Legend

Symbol	Description	Unit
amax	Maximum acceleration travel	m/s2
C	Dynamic load capacity	N
C0	Static load capacity	N
m	Mass	kg
ML	Dynamic longitudinal moment load capacity	Nm
ML0	Static longitudinal moment load capacity	Nm
Mt	Dynamic torsional moment load capacity	Nm
Mt0	Static torsional moment laod capacity	Nm
vmax	Maximum permissible speed	m/s
μ	Friction coefficient

General Notes

The general technical data and calculations apply to all Ball Rail Systems i.e. to all Ball Runner Blocks and Ball Guide Rails. Specific technical data relating to the individual Ball Runner Blocks and Ball Guide Rails is listed separately.

Preload classes

To cover the widest possible range of applications, Rexroth Ball Runner Blocks are available in different preload classes.

The following preload classes are available:

Ball Runner Block without preload (preload class C0) Ball Runner Blocks with moderate preload (preload class C1) Ball Runner Blocks with average preload (preload class C2) Ball Runner Blocks with high preload (preload class C3)

To prevent reductions to the service life, the preload should not exceed 1/3 of the load on bearing F.

In general, the rigidity of the Ball Runner Block rises with increasing preload. If vibrations occur, select a correspondingly high preload (≥ preload class C2).

Guide systems with parallel rails

When choosing the preload class, pay attention to permissible parallelism offset of rails too ("Accuracy class selection criterion").

When specifying ball rail systems of accuracy class N, we recommend preload class C0 or C1 to avoid distortive stress due to the tolerances.

Accuracy classes

System preload

a)	For O-ring
	Size 20/40: Ø 5 · 1.0 (mm)
	Size 25/70: Ø 5 · 1.0 (mm)
	Open lube port if necessary (see general technical notes and information in the "Maintenance" section).
b)	Recommended position for pin holes (dimension E4 see general technical notes and information in the "Installation" section).
	Rough-drilled holes may be present here from manufacturing.
	These may be bored open.
c)	Lube nipple, size 20/40:
	Funnel-type lube nipple DIN 3405-A M3x5, B2 = 1.6 mm
	When using different lube nipples, pay attention to the screw-in depth of 5 mm!
	Lube nipple, size 25/70:
	Hydraulic-type lube nipple DIN 71412-A M6x8, B2 = 9.5 mm
	When using different lube nipples, pay attention to the screw-in depth of 8 mm!
	The lube nipple is included in the scope of delivery (not installed). Connection is possible on all sides.
d)	Sealing plugs may be present here from manufacturing. Remove these prior to mounting.

Dimensions

Size		20/40 1)	25/70
A	mm	80	120
A1	mm	40	60
A2	mm	42	69
A3	mm	19	25.5
B	mm	73	105
B1	mm	51.3	76.5
E1	mm	70	107
E2	mm	40	60
E8	mm	18	35
E8.1	mm	53.4	83.5
E9	mm	3.4	4.9
E9.1	mm	8.1	11.3
H	mm	27	35
H1	mm	22.5	29.75
H2	mm	18.3	23.55
K1	mm	10.6	15.4
K2	mm	11	15.5
K3	mm	3.5	5.2
K4	mm	3.5	5.2
N1	mm	7.7	9.35
N2	mm	3.7	7.05
N6		12.5 mm ±0.5	14.4 mm ±0.5
S1	mm	5.3	6.7
S2	mm	M6	M8
ØS5	mm mm	4.4	7
S9		M2.5x1.5 mm +3	M3x2 mm +4.5
T	mm	60	80
V1	mm	6	7.5