THK LM Guide linear guideways
THK Linear Guideways
THK LM Guide profile rail linear guideways -- SHS, HSR, SSR, SRG and related families with catalogue engineering data, preload, accuracy, life formulas, SSR ordering codes and bounded comparison reference.
THK LM Guide portfolio
THK LM Guide profile rail linear guideways span caged-ball, full-ball and roller technologies for machine tools, semiconductor equipment, medical imaging and industrial automation. This page publishes catalogue-grounded engineering reference data from the THK engineering reference source. Golden Bearing Company does not imply authorization, dealership or stocking unless that relationship is stated on a dedicated GBC page.
Searchable configuration examples include: SHS-C, SHS-V, SHS-R, HSR-A, HSR-C, HSR-R, HSR20M1R1C1, SSR-XTB, SSR-XW, SSR-XV, SSR25XV1ZZC1J, SHW-CA, SHW-CR, SHW17CR2QZKKHHC1M, SRG-C, SRG-LV, SRG25LV1ZZC0, SRS-S, SRS-M, EPF7M, EPF9M, EPF12M, SCR15, HCR25A2UUC1.
THK LM Guide technology types
Engineering theme
Caged Ball LM Guides
Patented Caged Ball separators eliminate ball-to-ball collision, reduce heat and noise, and extend grease maintenance intervals. Families include SHS, SSR, SHW, SRS, SCR and EPF.
Engineering theme
Full-Ball LM Guides
Traditional full ball recirculation for maximum static and dynamic load in full-complement designs. Global standard HSR and compact SR are widely specified; semi-standard sizes HSR85 to HSR150 are documented.
Engineering theme
Roller LM Guides
Cylindrical rollers provide line contact and ultra-high rigidity for heavy machine tool axes. SRG is the primary ultra-heavy roller family in the supplied extract.
Engineering theme
Specialty guides
Curved HCR, straight-curved HMG, cross guides SCR/CSR/MX, miniature EPF, and separate-rail HR and GSR families address non-linear or compact duty beyond standard profile rails.
Caged ball family reference
Documented caged ball LM Guide families and size envelopes from the catalogue extract. SVR/SVS sizes are not fully tabulated in the supplied reference.
| Series | Type | Block configurations | Documented sizes |
|---|---|---|---|
| SHS | Global standard caged ball | SHS-C, SHS-LC, SHS-V, SHS-LV, SHS-R, SHS-LR, SHS-YR | SHS15, SHS20, SHS25, SHS30, SHS35, SHS45, SHS55, SHS65 |
| SSR | Compact radial caged ball | SSR-XTB, SSR-XW, SSR-XV | SSR15, SSR20, SSR25, SSR30, SSR35 |
| SHW | Wide rail, low CG | SHW-CA, SHW-CR, SHW-HR | SHW12, SHW14, SHW17, SHW21, SHW27, SHW35, SHW50 |
| SRS | Miniature caged ball | SRS-S, SRS-M, SRS-N, SRS-WS, SRS-WM, SRS-WN | SRS5, SRS7, SRS9X, SRS9, SRS12, SRS15, SRS20, SRS25 |
| SVR/SVS | Ultra heavy load caged ball | LaCS / ZZHH / KKHH options documented | Family referenced; full size table not in supplied catalogue extract |
| SCR | Caged ball cross guide | Per catalogue | SCR15, SCR20, SCR25, SCR30, SCR35, SCR45, SCR65 |
| EPF | Miniature guaranteed stroke | EPF7M, EPF9M, EPF12M | EPF7M, EPF9M, EPF12M |
Full-ball family reference
Documented full-ball families. RSR, GSR and NSR-TBC are referenced in the catalogue; complete size matrices require manufacturer verification.
| Series | Type | Block configurations | Documented sizes |
|---|---|---|---|
| HSR | Global standard full-ball | HSR-A, HSR-LA, HSR-C, HSR-LC, HSR-R, HSR-LR, HSR-YR, HSR-M1 | HSR8 to HSR65; semi-standard HSR85, HSR100, HSR120, HSR150 |
| SR | Compact radial full-ball | SR-W, SR-TB, SR-SB, SR-V; SR-M1 | SR15, SR20, SR25, SR30, SR35, SR45, SR55 |
| HRW | Wide rail full-ball | HRW-CA, HRW-CR | HRW12, HRW14, HRW17, HRW21, HRW27, HRW35, HRW50, HRW60 |
| HR | Separate LM guide (two-piece rail) | Per catalogue | HR918 through HR60125 (T variants documented) |
| RSR | Miniature full-ball | RSR-M1 to 150 C noted | Size table not fully specified in supplied extract |
| GSR / GSR-R | Separate rail; rack and pinion option | Per catalogue | Family referenced; sizes not fully specified in supplied extract |
| NSR-TBC | Self-aligning heavy load | Per catalogue | Family referenced; sizes not fully specified in supplied extract |
THK catalogue states SHS outer dimensions are interchangeable with traditional HSR full-ball series within the THK product line. This is an intra-THK statement, not a cross-brand interchange claim.
Roller and specialty family reference
Roller and specialty families from the catalogue extract. SRG maximum speed and acceleration are not specified in the supplied reference.
| Series | Type | Block configurations | Documented sizes |
|---|---|---|---|
| SRG | Ultra-high rigidity roller | SRG-C, SRG-LC, SRG-V, SRG-LV, SRG-SLV | SRG20, SRG25, SRG30, SRG35, SRG45, SRG55, SRG65, SRG85, SRG100 |
| SRN | Low centre-of-gravity roller | Per catalogue | Family referenced; sizes not fully specified in supplied extract |
| SRW | Wide rail roller | Per catalogue | SRW70, SRW85, SRW100 |
| HCR | R-Guide curved rail | HCR-A and related | HCR12, HCR15, HCR25, HCR35, HCR45, HCR65 |
| HMG | Straight-curved recirculating | Per catalogue | Family referenced in catalogue extract |
| CSR / MX | Cross caged ball miniature/medium | Per catalogue | Family referenced; sizes not fully specified in supplied extract |
Radial clearance and preload (SHS / SCR)
Radial clearance values in micrometres for SHS and SCR sizes 15 to 65. HSR85, HSR100, HSR120 and HSR150 clearance values are not in the supplied extract.
| Model size | Normal (no symbol) | Light preload C1 | Medium preload C0 |
|---|---|---|---|
| SHS15 / SCR15 | -5 to 0 um | -12 to -5 um | Not specified |
| SHS20 / SCR20 | -6 to 0 um | -12 to -6 um | -18 to -12 um |
| SHS25 / SCR25 | -8 to 0 um | -14 to -8 um | -20 to -14 um |
| SHS30 / SCR30 | -9 to 0 um | -17 to -9 um | -27 to -17 um |
| SHS35 / SCR35 | -11 to 0 um | -19 to -11 um | -29 to -19 um |
| SHS45 / SCR45 | -12 to 0 um | -22 to -12 um | -32 to -22 um |
| SHS55 / SCR55 | -15 to 0 um | -28 to -16 um | -38 to -28 um |
| SHS65 / SCR65 | -18 to 0 um | -34 to -22 um | -45 to -34 um |
Accuracy grades
THK accuracy designations H, P, SP and UP for SHS, HSR and SSR families. Running parallelism numeric chart for UP grade requires the primary catalogue table.
| Grade | Height tolerance | Width tolerance W2 | Height variation H max | Width variation W2 max |
|---|---|---|---|---|
| H (High) | ±0.040 mm | ±0.040 mm | Per catalogue chart | Per catalogue chart |
| P (Precision) | Per catalogue | ±0.025 mm | 0.007 mm | 0.007 mm |
| SP (Super Precision) | Per catalogue | ±0.015 mm | Per catalogue chart | Per catalogue chart |
| UP (Ultra Precision) | Running parallelism vs rail length | Per catalogue chart | Per catalogue chart | Per catalogue chart |
Materials, coatings, temperature and QZ lubrication
Material suffixes, high-temperature M1 options, coatings and vacuum grease references:
| Option | Designation | Application / limit |
|---|---|---|
| Carbon steel | No symbol (default) | Standard blocks and rails |
| Stainless steel | M suffix (rail, block, rolling elements) | Vacuum, cleanroom, corrosive duty |
| High temperature | M1 suffix (HSR-M1, SR-M1, RSR-M1) | Continuous up to 150 C |
| Standard temperature limit | Non-M1 blocks and seals | Plastic endplates and rubber seals limited to 80 C |
| Armoloy coating | R-BC | Wear and corrosion surface treatment |
| THK coatings | AP-C, AP-CF, AP-HC | Corrosion prevention |
| Vacuum grease | AFE-CA, AFF | Stainless with zero anti-rust oil |
QZ lubricator: Oil-impregnated pad provides continuous lubrication and extends maintenance intervals. Standard grease nipple port may be occupied; specify mounting orientation to THK if both QZ and nipple access are required.
Seals and contamination protection
Seal and scraper codes used in THK ordering (SSR decoder extract):
| Code | Description |
|---|---|
| UU | End seals |
| SS | End and side seals |
| DD | Double end seals and side seals |
| ZZ | End and side seals plus metal scrapers |
| KK | Double end seals, side seals and metal scrapers |
| HH | LaCS laminated contact scraper |
| GG | Light-resistance contact scraper |
| PP | Light-resistance contact scraper plus side/inner seal |
Additional catalogue features include LaCS laminated contact scrapers, plate covers over rail counterbores, and GC metal counterbore caps for a seamless rail face.
Load factor f_W
Speed-dependent load factor f_W from the THK LM Guide extract:
| Speed condition | Load factor f_W |
|---|---|
| V <= 0.25 m/s, smooth operation | 1.0 to 1.2 |
| 0.25 < V <= 1.0 m/s, weak impact | 1.2 to 1.5 |
| 1.0 < V <= 2.0 m/s, medium impact | 1.5 to 2.0 |
| V > 2.0 m/s, heavy impact | 2.0 to 3.5 |
Selection methodology and life formulas
THK catalogue nominal life equations (symbols as in LM Guide extract):
- Ball-type nominal life L (km): L = 50 × ( (fH × fT × fC / fW) × (C / PC) )3
- Roller-type nominal life L (km): L = 50 × ( (fH × fT × fC / fW) × (C / PC) )10/3 (applies to SRG and other roller guides)
- Oil-free LM Guides: L = 50 × ( F0 / (fW × PC) )1.57
- Service life in hours: Lh = (L × 106) / (2 × ls × n1 × 60)
- Fluctuating load (step profile): Pm = cube root of (1/L) × sum(Pi3 × Li); use exponent 10/3 for roller guides
- Monotonic fluctuating load: Pm ≈ (Pmin + 2 × Pmax) / 3
Where C is basic dynamic load rating (N), PC is calculated block load (N), fH is hardness factor (1.0 at 58 to 64 HRC raceway), fT is temperature factor, fC is contact factor for parallel blocks, and fW is load factor from the speed table. Numerical fC and fT tables are not in the supplied extract -- request manufacturer data for final life calculations.
Caged ball vs full-ball vs roller (engineering distinction)
| SHS (caged ball) vs HSR (full-ball) | Caged ball reduces ball friction, noise and heat; maintenance intervals up to 10x full-complement per catalogue FAQ. SHS outer dimensions align with HSR within the THK line. |
|---|---|
| SRG roller vs SHS/HSR ball | Roller line contact increases rigidity and damping for heavy machine tool cuts. SRG block configurations include SRG-C, SRG-LC, SRG-V, SRG-LV and SRG-SLV. |
| Circular-arc DF vs gothic-arch (catalogue comparison) | THK circular-arc groove uses 45-degree contact, 4-row 2-point contact with low differential slip and high self-adjustment for mounting errors. Gothic-arch comparison in THK literature uses 4-point 2-row contact with higher differential slip under preload. |
Mounting and lubrication
THK guides support horizontal, inverted, vertical, slant and wall mounting. For non-horizontal orientations, gravity-fed grease may seep from the block -- specify orientation when ordering so lubrication paths are correct.
Jointed rails: T suffix designates butt-joined rails for strokes beyond standard maximum length (approximately 3000 mm). Match-marks align preload across joints.
Mounting hole Y suffix: Alternative hole size -- e.g. HSR15/SR15 standard M3, Y = M4; HSR25/SR25 standard M5, Y = M6.
Bottom tapping: K suffix -- rail tapped from bottom instead of top counterbores.
Documented applications
Catalogue-mapped application families. Application notes are reference guidance only and do not guarantee suitability for a specific machine without engineering review.
| Application | Documented series families |
|---|---|
| Machine tools (machining centres, lathes, grinding) | SVR/SVS, SRG (catalogue application mapping) |
| Semiconductor / vacuum / cleanroom | SHS, SSR, SHW, SRS stainless M with AFF/AFE-CA grease |
| Medical / imaging / lab automation | SRS miniature, EPF |
| Industrial automation / gantries | SHW, HRW, SSR |
| Seismic isolation (specialty) | Model TSD (custom heavy-load LM Guides) |
SSR ordering code decoder
Example ordering string: SSR25 XV 3 QZ ZZ HH C1 F M J S + 4800L Y H K Z T F M E J -II
- SSR25 -- Model and size (SSR15, SSR20, SSR25, SSR30, SSR35).
- XV -- Block style: XTB rectangular flanged, XW standard flanged, XV low-profile rectangular.
- 3 -- Number of blocks on one rail.
- QZ -- QZ lubricator attached (omit if not fitted).
- ZZ -- Seal designation: UU, SS, DD, ZZ, KK (see seal table).
- HH -- Contact scraper: HH LaCS, GG, PP.
- C1 -- Radial clearance: omit normal, C1 light preload, CS special clearance.
- F -- Block surface coating (drawing/spec required) or omit.
- M -- Stainless block and balls or omit for carbon steel.
- J -- Bellow preparation holes on block or omit.
- S -- Non-standard block modification E or S, or omit.
- 4800L -- Rail length in millimetres.
- Y -- Alternative mounting hole size (e.g. HSR15/SR15 M3 standard, Y = M4).
- H -- Accuracy: omit normal, H, P, SP, UP.
- K -- Bottom-mount tapped rail or omit.
- Z -- Steel tape protector recess or omit.
- T -- Jointed rail for extreme lengths or omit.
- F / M / E / J -- Rail coating, material, modification, bellow prep (same vocabulary as block).
- -II -- Set axis quantity: -II two axes, -III three, -IV four, or omit for one axis.
Full HSR, SHS and SRG decoders use the same THK ordering vocabulary but are not fully enumerated in the supplied catalogue extract. Confirm field meanings against the manufacturer ordering guide before quoting.
Manufacturer comparison reference (qualified)
HIWIN publishes a dimensional comparison chart that references THK families alongside other market-reference products. This is research data only. Golden Bearing Company does not guarantee interchangeability, equivalence or substitution without engineering verification.
| HIWIN block type | Market-reference families (HIWIN comparison chart) |
|---|---|
| HGH-CA | THK HSR-RSS/SHS-R/V, IKO LWHD-B, INA MHD, Rexroth KUSE-H, NSK 1621, SKF LY-AN, SBC SBG-SL, ABBA BRH-B, AMT MSA-S |
| HGW-CA | THK HSR-A/SHS-C |
Qualification: Only size 20 is the same. The rest have different heights.
Catalogue and commercial boundary
Some THK families, load ratings (C/C0), contact factor f_C, temperature factor f_T, HSR85 to HSR150 clearance, and SRG speed/acceleration limits are not fully specified in the supplied catalogue extract. Share complete rail/block designation, orientation and load duty for engineering quotation. Listing THK on this page does not imply Golden Bearing Company distributes, stocks, authorises or represents THK unless separately confirmed.
Common questions
SHS uses Caged Ball technology with separators that reduce ball-to-ball friction, noise and heat, extending maintenance intervals. HSR is the traditional full-ball recirculating design. THK catalogue states SHS outer dimensions are interchangeable with HSR within the THK product line.
Grades H (High), P (Precision), SP (Super Precision) and UP (Ultra Precision) are documented for SHS, HSR and SSR families. Height and width tolerances vary by grade; UP running parallelism depends on rail length per catalogue chart.
Normal clearance uses no symbol. C1 is light preload. C0 is medium preload where specified (e.g. SHS20 and larger). Values are in micrometres and vary by size -- see the clearance table on this page for SHS15 through SHS65.
M1 suffix supports continuous operation up to 150 C on documented families such as HSR-M1, SR-M1 and RSR-M1. Standard blocks with polymer endplates and rubber seals are limited to 80 C continuous.
Ball guides use exponent 3: L = 50 x ((f_H x f_T x f_C / f_W) x (C / P_C))^3 km. Roller guides use exponent 10/3. Service life in hours converts using stroke length and cycle frequency. Request f_C and f_T tables from the manufacturer for final calculations.
QZ is an oil-impregnated lubricator that maintains a continuous oil film and extends maintenance intervals. It may occupy the standard grease nipple port; specify orientation to THK if both QZ and nipple access are required.
See the SSR decoder on this page. Example: SSR25 XV 3 QZ ZZ HH C1 + 4800L H -II. Fields cover block style, seals, preload, materials, rail length, accuracy, jointed rails and axis set quantity.
The chart maps HIWIN block types to market-reference families including THK HSR and SHS configurations. Qualification: only size 20 is the same; the rest have different heights. This is reference data only and does not confirm cross-brand substitution.
SRG addresses ultra-high rigidity machine tool duty where line-contact rollers reduce elastic deformation and increase damping under heavy cutting loads. Documented sizes include SRG20 through SRG100 with block types SRG-C, SRG-LC, SRG-V, SRG-LV and SRG-SLV.
Per-size C/C0 load ratings, contact factor f_C table, temperature factor f_T graph, HSR85 to HSR150 clearance, SRG speed/acceleration numerics, and complete size tables for RSR, GSR, NSR-TBC, SRN and CSR/MX require manufacturer verification.
Request an Engineering Quote
Share shaft bore, speed, torque duty and ordering designation for THK Linear Guideways. Send THK series (SHS, HSR, SSR, SRG, etc.), size, block style, preload, accuracy grade, stroke, orientation and load duty for engineering quotation.