Allar rúllulegur þurfa lágmarksálag. Ef of lítið álag er beitt munu rúllueiningarnar renna í stað þess að rúlla. Þegar rennur á sér stað er smurfilman þurrkuð af vegna minni en ákjósanlegrar yfirborðshreyfingar, sem aftur leiðir til snertingar málms á milli málms, sem dregur úr endingartíma legunnar.

Formúla til að reikna lágmarksálag
Lágmarksálagskröfur eru mismunandi eftir leguhönnun. Almennt séð, því stærra sem snertiflöturinn er á milli veltihlutanna og hlaupabrautanna, því meiri lágmarksálag sem krafist er. Þess vegna hafa sívalur rúllulegur hærri lágmarksálagskröfur en djúpgrópkúlulegur. Innri rúmfræði burðar, vikmörk og yfirborðsáferð hafa einnig áhrif á lágmarksálagskröfur.
Dæmigerð formúla fyrir mat á lágmarksálagi er sem hér segir:
Jack lið
F{{0}}P/C > 0,01
rúllulegur
F{{0}}P/C > 0,02
Fyrir nákvæmari útreikning á lágmarksgildi geturðu vísað til útreikningsformúlunnar sem gefið er af hverju vörumerki, vegna þess að innri hönnun legur hvers vörumerkis mun hafa lúmskur munur, þannig að útreikningur á lágmarksálagi mun hafa ákveðinn mun.
Fyrir góða leguhönnun verður minni lágmarksálagsþörf að vera eitt af markmiðunum sem stefnt er að með hönnuninni.
Tekið saman
Almennar viðmiðunarreglur: Mælt er með því að stilla líftíma legu á ekki yfir 100,000 klst. við verstu samsetningu álags.
Ef ekki er hægt að uppfylla lágmarksálagskröfur legunnar getur hönnuður valið legu með lægri lágmarksálagskröfu, til dæmis: valið legu með minni stærð. Eða aukið burðarálagið, algengasta leiðin til að auka lágmarksálag lagsins er forhleðsluaðferðin með stöðugum þrýstingi.
Fyrir neðan Kúlulaga rúllulegur í yfirstærð eru fáanlegar til afhendingar
| 230/1000-MB | 1000x1420x308 |
| 238/1000-MB | 1000x1220x165 |
| 248/1700-MB | 1700x2060x355 |
| 238/670-B-MB | 670x820x112 |
| 239/560-B-MB | 560x750x140 |
| 23980-BK-MB | 400x540x106 |
| 230/900-B-MB | 900x1280x280 |
| 230/950-B-MB | 950x1360x300 |
| 231/670-B-MB | 670x1090x336 |
| 231/750-B-MB | 750x1220x365 |
| 230/710-B-MB | 710x1030x236 |
| 230/750-K-MB | 750x1090x250 |
| 231/600-K-MB | 600x980x300 |
| 230/670-B-MB | 670x980x230 |
| 232/600-B-MB | 600x1090x388 |
| 232/670-B-MB | 670x1220x438 |
| 232/530-K-MB | 530x980x355 |
| 232/560-K-MB | 560x1030x365 |
| 238/750-B-MB | 750x920x128 |
| 238/850-K-MB | 850x1030x136 |
| 23960-BK-MB | 300x420x90 |
| 23992-BK-MB | 460x620x118 |
| 23996-BK-MB | 480x650x128 |
| 239/600-B-MB | 600x800x150 |
| 239/630-B-MB | 630x850x165 |
| 239/670-B-MB | 670x900x170 |
| 239/800-B-MB | 800x1060x195 |
| 239/950-B-MB | 950x1250x224 |
| 239/850-K-MB | 850x1120x200 |
| 239/900-K-MB | 900x1180x206 |
| 239/500-K-MB | 500x670x128 |
| 239/530-K-MB | 530x710x136 |
| 239/710-K-MB | 710x950x180 |
| 23940-SK-MB | 200x280x60 |
| 23936-SK-MB | 180x250x52 |
| 23944-SK-MB | 220x300x60 |
| 240/670-B-MB | 670x980x308 |
| 240/710-B-MB | 710x1030x315 |
| 240/750-B-MB | 750x1090x335 |
| 240/850-B-MB | 850x1220x365 |
| 240/900-B-MB | 900x1280x375 |
| 240/950-B-MB | 950x1360x412 |
| 240/800-B-MB | 800x1150x345 |
| 241/670-B-MB | 670x1090x412 |
| 241/750-B-MB | 750x1220x475 |
| 241/850-B-MB | 850x1360x500 |
| 248/670-B-MB | 670x820x150 |
| 241/710-B-MB | 710x1150x438 |
| 241/600-B-MB | 600x980x375 |
| 248/750-B-MB | 750x920x170 |
| 248/800-B-MB | 800x980x180 |
| 249/800-B-MB | 800x1060x258 |
| 249/850-B-MB | 850x1120x272 |
| 239/750-K-MB | 750x1000x185 |
| 249/710-B-MB | 710x950x243 |
| 249/950-B-MB | 950x1250x300 |
| 238/710-K-MB | 710x870x118 |
| 238/600-K-MB | 600x730x98 |
| 230/850-B-MB | 850x1220x272 |
| 231/710-B-MB | 710x1150x345 |
| 248/900-B-MB | 900x1090x190 |
| 231/800-K-MB | 800x1280x375 |
| 248/530-B-MB | 530x650x118 |
| 248/710-B-MB | 710x870x160 |
| 231/900-B-MB | 900x1420x412 |
| 231/630-B-MB | 630x1030x315 |
| 232/630-B-MB | 630x1150x412 |
| 248/560-B-MB | 560x680x118 |
| 241/630-B-MB | 630x1030x400 |
| 241/800-B-MB | 800x1280x475 |
| 248/500-B-MB | 500x620x118 |
| 231/850-B-MB | 850x1360x400 |
| 238/900-B-MB | 900x1090x140 |
| 232/750-B-MB | 750x1360x475 |
| 249/670-B-MB | 670x900x230 |
| 241/950-B-MB | 950x1500x545 |
| 249/750-B-MB | 750x1000x250 |
| 248/600-B-MB | 600x730x128 |
| 230/800-K-MB | 800x1150x258 |
| 232/710-B-MB | 710x1280x450 |
| 238/800-B-MB | 800x980x136 |
| 232/800-K-MB | 800x1420x488 |
| 239/1060-MB1 | 1060x1400x250 |
| 22236-E1-XL-K | 180x320x86 |
| 22226-E1-XL-K | 130x230x64 |
| 22326-E1-XL-K | 130x280x93 |
| 23144-BE-XL-K | 220x370x120 |
| 22332-BE-XL-K | 160x340x114 |
| 23156-BE-XL-K | 280x460x146 |
| 22336-BE-XL-K | 180x380x126 |
| 23238-BE-XL-K | 190x340x120 |
| 22240-BE-XL-K | 200x360x98 |
| 22338-BE-XL-K | 190x400x132 |
| 22238-BE-XL-K | 190x340x92 |
| 22248-BE-XL-K | 240x440x120 |
| 22244-BE-XL-K | 220x400x108 |
| 22334-BE-XL-K | 170x360x120 |
| 22340-BE-XL-K | 200x420x138 |
| 23056-BE-XL-K | 280x420x106 |
| 23148-BE-XL-K | 240x400x128 |
| 23152-BE-XL-K | 260x440x144 |
| 23240-BE-XL-K | 200x360x128 |
| 23052-BE-XL-K | 260x400x104 |
| 23044-BE-XL-K | 220x340x90 |
| 23244-BE-XL-K | 220x400x144 |
| 23248-BE-XL-K | 240x440x160 |
| 230/1000-MB | 1000x1420x308 |
| 238/1000-MB | 1000x1220x165 |
| 248/1700-MB | 1700x2060x355 |
| 238/670-B-MB | 670x820x112 |
| 239/560-B-MB | 560x750x140 |
| 23980-BK-MB | 400x540x106 |
| 230/900-B-MB | 900x1280x280 |
| 230/950-B-MB | 950x1360x300 |
| 231/670-B-MB | 670x1090x336 |
| 231/750-B-MB | 750x1220x365 |
| 230/710-B-MB | 710x1030x236 |
| 230/750-K-MB | 750x1090x250 |
| 231/600-K-MB | 600x980x300 |
| 230/670-B-MB | 670x980x230 |
| 232/600-B-MB | 600x1090x388 |
| 232/670-B-MB | 670x1220x438 |
| 232/530-K-MB | 530x980x355 |
| 232/560-K-MB | 560x1030x365 |
| 238/750-B-MB | 750x920x128 |
| 238/850-K-MB | 850x1030x136 |
| 23960-BK-MB | 300x420x90 |
| 23992-BK-MB | 460x620x118 |
| 23996-BK-MB | 480x650x128 |
| 239/600-B-MB | 600x800x150 |
| 239/630-B-MB | 630x850x165 |
| 239/670-B-MB | 670x900x170 |
| 239/800-B-MB | 800x1060x195 |
| 239/950-B-MB | 950x1250x224 |
| 239/850-K-MB | 850x1120x200 |
| 239/900-K-MB | 900x1180x206 |
| 239/500-K-MB | 500x670x128 |
| 239/530-K-MB | 530x710x136 |
| 239/710-K-MB | 710x950x180 |
| 23940-SK-MB | 200x280x60 |
| 23936-SK-MB | 180x250x52 |
| 23944-SK-MB | 220x300x60 |
| 240/670-B-MB | 670x980x308 |
| 240/710-B-MB | 710x1030x315 |
| 240/750-B-MB | 750x1090x335 |
| 240/850-B-MB | 850x1220x365 |
| 240/900-B-MB | 900x1280x375 |
| 240/950-B-MB | 950x1360x412 |
| 240/800-B-MB | 800x1150x345 |
| 241/670-B-MB | 670x1090x412 |
| 241/750-B-MB | 750x1220x475 |
| 241/850-B-MB | 850x1360x500 |
| 248/670-B-MB | 670x820x150 |
| 241/710-B-MB | 710x1150x438 |
| 241/600-B-MB | 600x980x375 |
| 248/750-B-MB | 750x920x170 |
| 248/800-B-MB | 800x980x180 |
| 249/800-B-MB | 800x1060x258 |
| 249/850-B-MB | 850x1120x272 |
| 239/750-K-MB | 750x1000x185 |
| 249/710-B-MB | 710x950x243 |
| 249/950-B-MB | 950x1250x300 |
| 238/710-K-MB | 710x870x118 |
| 238/600-K-MB | 600x730x98 |
| 230/850-B-MB | 850x1220x272 |
| 231/710-B-MB | 710x1150x345 |
| 248/900-B-MB | 900x1090x190 |
| 231/800-K-MB | 800x1280x375 |
| 248/530-B-MB | 530x650x118 |
| 248/710-B-MB | 710x870x160 |
| 231/900-B-MB | 900x1420x412 |
| 231/630-B-MB | 630x1030x315 |
| 232/630-B-MB | 630x1150x412 |
| 248/560-B-MB | 560x680x118 |
| 241/630-B-MB | 630x1030x400 |
| 241/800-B-MB | 800x1280x475 |
| 248/500-B-MB | 500x620x118 |
| 231/850-B-MB | 850x1360x400 |
| 238/900-B-MB | 900x1090x140 |
| 232/750-B-MB | 750x1360x475 |
| 249/670-B-MB | 670x900x230 |
| 241/950-B-MB | 950x1500x545 |
| 249/750-B-MB | 750x1000x250 |
| 248/600-B-MB | 600x730x128 |
| 230/800-K-MB | 800x1150x258 |
| 232/710-B-MB | 710x1280x450 |
| 238/800-B-MB | 800x980x136 |
| 232/800-K-MB | 800x1420x488 |
| 239/1060-MB1 | 1060x1400x250 |
| 22236-E1-XL-K | 180x320x86 |
| 22226-E1-XL-K | 130x230x64 |
| 22326-E1-XL-K | 130x280x93 |
| 23144-BE-XL-K | 220x370x120 |
| 22332-BE-XL-K | 160x340x114 |
| 23156-BE-XL-K | 280x460x146 |
| 22336-BE-XL-K | 180x380x126 |
| 23238-BE-XL-K | 190x340x120 |
| 22240-BE-XL-K | 200x360x98 |
| 22338-BE-XL-K | 190x400x132 |
| 22238-BE-XL-K | 190x340x92 |
| 22248-BE-XL-K | 240x440x120 |
| 22244-BE-XL-K | 220x400x108 |
| 22334-BE-XL-K | 170x360x120 |
| 22340-BE-XL-K | 200x420x138 |
| 23056-BE-XL-K | 280x420x106 |
| 23148-BE-XL-K | 240x400x128 |
| 23152-BE-XL-K | 260x440x144 |
| 23240-BE-XL-K | 200x360x128 |
| 23052-BE-XL-K | 260x400x104 |
| 23044-BE-XL-K | 220x340x90 |
| 23244-BE-XL-K | 220x400x144 |
| 23248-BE-XL-K | 240x440x160 |
