Plummer Blocks

Housings

The following is an extract from the SKF catalogue, edited for this Handbook.

A variety of housings are available to suit different requirements and applications.

SNA plummer blocks are a development of the SN plummer blocks. The dimensions of both SNA and SN housings follow ISO/R 113 and the housings of series SNA 5 and SNA 6 are interchangeable with those of SN 5 and SN 6, respectively. The SNA housings have much greater strength however.

Where even greater strength is required SSNAD housings can be supplied. A standard range of housings from size 511-609 is available made of spheroidal graphite cast iron. The bearing seating is machined to tolerance H8.

These housings carry the designation prefix SSNAD, e.g. SSNAD 511 TA.

i. Drilling

The foot of SSNAD housings is solid and without bolt holes. These should be drilled according to the instructions given in the following table. SSNAD and SNA housings are otherwise identical and the same bearings and accessories may be used.

Table indicating base drilling dimensions.

For two holes

For four holes

Housing without seals Dimensions mm
For two holes For four holes

Designation

 J N1 J1 J2 N2
SSNAD 511-609 210 18 200 35 15
SSNAD 512-610 210 18 200 35 15
SSNAD 513-611 230 18 220 40 15
SSNAD 515-612 230 18 220 40 15
SSNAD 516-613 260 22 250 50 15
SSNAD 517 260 22 250 50 15
SSNAD 518-615 290 22 280 50 18
SSNAD 519-616 290 22 280 50 18
SSNAD 520-617 320 26 300 60 18
SSNAD 522-619 350 26 320 70 18
SSNAD 524-620 350 26 330 70 18
SSNAD 526 380 28 370 70 22
SSNAD 528 420 35 400 80 26
SSNAD 530 450 35 430 90 26
SSNAD 532 470 35 450 90 26

ii. Loading and strength of plummer block housings.

Plummer blocks are designed to accommodate loads acting at right angles to the base. If the direction of load is not perpendicular to the base care should be taken to see that the housing, cap bolts and holding down bolts have sufficient strength to carry the loads involved.

Approximate values for the breaking load for the housings and the yield point for the cap bolts are given in the tables below.

To obtain the permissible load, the values are divided by a factor selected with regard to safety requirements.

For general engineering purposes a safety factor of 6 is generally applied for the housings and a factor of 3 for the bolts.

Approximate values of the breaking load (P) for the housings, and the yield point (Q) for the cap bolts are given in the following tables for different radial directions of loading.

When the load acts at an angle of 55 deg. the cap bolts carry no load and 'Q' is always greater than 'P' when the load acts at an angle of 90 deg. 

In the axial direction the breaking load is approximately 65 % of P180 deg.

Table showing strength of SNA and SSNAD plummer blocks

Strength of SNA and SSNAD plummer block housing
Housing Breaking load for SNA housings * Yield point for the two cap bolts
SNA housings SSNAD housings
Size P55° P90° P120° P150° P180° Q120° Q150° Q180° Q120° Q150° Q180°
-- kN (1kN = 225lbf) kN (1kN = 225lbf)
505 130 80 60 50 65 90 50 45 -- -- --
506-605 140 85 65 55 70 90 50 45 -- -- --
507-606 160 95 75 65 80 90 50 45 -- -- --
508-607 180 110 80 70 90 90 50 45 -- -- --
509 190 115 85 75 95 90 50 45 -- -- --
510-608 220 130 100 90 110 90 50 45 -- -- --
511-609 230 140 105 95 115 130 70 65 290 160 145
512-610 250 150 110 100 125 130 70 65 290 160 145
513-611 280 170 125 110 140 130 70 65 290 160 145
515-612 340 205 155 135 170 130 70 65 290 160 145
516-613 360 215 160 145 180 230 125 115 290 160 145
517 400 240 180 160 200 230 125 115 290 160 145
518-615 460 280 210 180 230 440 240 220 540 300 270
519-616 480 290 220 190 240 440 240 220 540 300 270
520-617 520 310 230 210 260 620 340 310 850 470 425
522-619 620 370 280 250 310 620 340 310 850 470 425
524-620 720 430 320 290 360 620 340 310 850 470 425
526 820 490 370 330 410 900 500 450 1220 670 610
528 960 570 430 390 480 900 500 450 1220 670 610
530 1100 660 490 440 550 900 500 450 1220 670 610
532 1130 780 580 520 650 900 500 450 1220 670 610

* = SSNAD housings have approximately twice this strength.

Table showing strength of SN plummer blocks

Strength of SN plummer block housing
Housing Breaking load for the housings * Yield point for the two cap bolts
Designation P55 P90 P120 P150 P180 Q120 Q150 Q180
-- kN (1kN = 225lbf) kN (1kN = 225lbf)
SN505 -- 70 40 30 30 35 80 45 40
SN506 SN605 80 50 35 30 40 80 45 40
SN507 SN606 90 55 40 35 45 80 45 40
SN508 SN607 100 60 45 40 50 80 45 40
SN509 -- 110 65 50 45 55 80 45 40
SN510 SN608 120 70 55 50 60 80 45 40
SN511 SN609 140 85 60 55 70 140 80 70
SN512 SN610 150 90 65 60 75 140 80 70
SN513 SN611 170 100 70 70 85 140 80 70
SN515 SN612 190 110 85 75 95 140 80 70
SN516 SN613 220 130 100 90 110 240 130 120
SN517 -- 240 140 110 95 120 240 130 120
SN518 SN615 260 160 120 100 130 240 130 120
-- SN616 280 170 130 110 140 240 130 120
SN520 SN617 340 200 150 140 170 540 300 270
SN522 -- 440 260 200 180 220 540 300 270
SN524 -- 520 310 230 210 260 540 300 270
SN526 -- 620 370 280 250 310 760 420 380
SN528 -- 720 430 320 290 360 1000 550 500
SN530 -- 860 520 390 340 430 1000 550 500
SN532 -- 1100 660 490 440 550 1000 550 500

* = Housing series SN2 and SN3 have the same strength as those of series SN5 and SN6 respectively.

Table showing dimensions of SN plummer blocks

Shaft dia. Housing Dimensions Mass Designation
da db A A1 H H1 H2 J L N N1 G
mm mm kg --
130 145 190 130 290 150 50 380 445 35 28 24 28.5 SN226
140 155 205 150 305 150 50 420 500 42 35 30 36.0 SN228
150 165 220 160 325 160 60 450 530 42 35 30 43.0 SN230
160 175 235 160 345 170 60 470 550 42 35 30 49.5 SN232

Table showing strength of SD plummer blocks

Strength of SD plummer block housing
Housing Breaking load for the housings Yield point for the four cap bolts
Designation P55 P90 P120 P150 P180 Q120 Q150 Q180
-- kN (1kN = 225lbf) kN (1kN = 225lbf)
SD3134 2100 1000 760 680 850 1500 830 750
SD3136 2400 1150 850 760 950 1500 830 750
SD3138 2700 1300 1000 880 1100 2000 1100 1000
SD3140 3200 1600 1150 1050 1300 2000 1100 1000
SD3144 4000 1900 1400 1400 1600 2000 1100 1000
SD3148 4200 2000 1500 1500 1700 3200 1800 1600
SD3152 4700 2300 1700 1700 1900 3200 1800 1600
SD3156 5000 2400 1800 1800 2000 3200 1800 1600
SD3160 6000 2900 2200 2200 2400 3200 1800 1600
SD3164 7000 3400 2500 2500 2800 3200 1800 1600

Table showing dimensions of SD plummer blocks

Ref No. d1 Spherical Roller Brg. + Adaptor Sleeve. A H1 H2 H L A1 J J1 J3 J4 J2 V d2 B
SDX 31106 500 231 / 530 CAK/W33 + OH31106 484 500 980 1100 1140 450 980 320 70 54 35 80 870 19
0
SDX 3196 450 23196 CAK/W33 + OH3196 458 470 910 1030 1040 440 880 310 70 54 35 80 790 17
0
SDX 3192 430 23192 CAK/W33 + OH3192 450 470 890 1010 1040 440 880 310 70 54 35 80 760 16
5
SDX 3188 410 23188 CAK/W33 + OH3188 436 440 840 960 940 400 810 280 64 48 35 70 720 15
5
SDX 3184 400 23184 CAK/W33 + OH3184 434 440 840 955 940 400 810 280 64 48 35 70 700 15
0
SDX 3180 380 23180 CAK/W33 + OH3180 400 390 755 860 880 380 760 280 64 48 35 70 700 14
0
SDX 3176 360 23176 CAK/W33 + OH3176 385 390 742 850 880 380 760 280 64 48 35 65 620 13
0
SDX 3172 340 23172 CAK/W33 + OH3172 380 360 700 800 830 350 700 240 64 48 30 50 600 12
8
SDX 3168 320 23168 CAK/W33 + OH3168 380 360 690 790 830 350 700 240 64 48 30 50 600 11
0