What Excavator Track Chain Do I Need? 4-Pin Pitch, Link Count & Shoe Bolt Fitment Checklist

An excavator track chain (track link assembly) is an articulated forged-steel pin-and-bushing loop whose replacement fitment is defined by six physical coordinates: (1) nominal 4-link pitch (135 to 260 mm), (2) total link count per side (37L to 53L+ across STD, LC, NLC, or SLR undercarriage frames), (3) track shoe 4-bolt hole spacing (transverse D/E x longitudinal B) and high-tensile bolt diameter (M12 to M27), (4) bushing outer diameter (D_b) and pin diameter (d_pin), (5) inner/outer link rail width (W_rail) and rail height (H_link), and (6) joint sealing and master link architecture (Sealed & Greased Polyurethane vs Dry vs Oil SALT, and Press-Fit Master Pin vs Split Alligator Master Link). Because heavy-equipment manufacturers build the same excavator model with multiple frame lengths and bolt grids, ordering a replacement track chain by machine tonnage, cab decal alone, or rough tape length causes $2,800 to $9,500 in wrong-part freight returns, un-tensionable track loops (45L STD vs 49L LC frame collisions), misaligned track shoe bolt holes (M18 vs M20), premature bushing failure within 200 operating hours on hooked drive sprockets, and unplanned machine downtime.

To eliminate fitment errors across Caterpillar, Komatsu, SANY, Hitachi, Kobelco, Doosan/Develon, Hyundai, Volvo, and Berco/ITM/ITR interchange systems, use the 6-Dimension Excavator Track Chain Fitment Verification Matrix below alongside your machine's ISO 10261:2021 17-character Product Identification Number (PIN) and stamped link forging number:

---

1. Six Mandatory Metrology Coordinates: Why Machine Tonnage and Rough Length Fail

When an excavator operator or fleet buyer searches "what excavator track chain do I need", the most common—and most expensive—procurement mistake is assuming that all excavators in the same tonnage class (e.g., "20-ton excavator" or "CAT 320 / Komatsu PC200 / SANY SY215") share an identical track chain. In heavy-equipment undercarriage engineering, machine tonnage only places a crawler within a general pitch family; it never locks physical interchangeability:

1. Undercarriage Frame Length Variants (STD vs. LC vs. NLC vs. SLR) Change Link Count (N_links) on the Exact Same Excavator Model: A 20-ton class crawler excavator running a 190.0 mm nominal pitch link assembly is factory-built in multiple track-frame lengths. A Standard (STD) undercarriage on a CAT 320 or Komatsu PC200-6/7/8 uses 45 links per side (unrolled new length = 45 * 190.0 mm = 8,550 mm). A medium frame (Hitachi EX200-3 or Komatsu PC200-3) uses 46 links per side (8,740 mm). A Long Crawler (LC) frame (SANY SY215C, Kobelco SK200-8, Hyundai R210-7, Komatsu PC200LC, CAT 320L / 225D) uses 49 links per side (9,310 mm—exactly 760 mm longer than the 45-link chain). Super Long Reach (SLR) and low-ground-pressure swamp frames use 51 to 54 links per side.
2. Internal Pin-to-Bushing Wear Elongates the Old Chain by 120 to 180+ mm (+2.5 to +4.0 mm per Link): As abrasive silica dust penetrates the pin-to-bushing interface over 3,500 to 5,000 operating hours, every joint wears radially. Measuring a single worn link center-to-center (1-pitch reading) or measuring the total unrolled length of a stretched chain laid on the shop floor embeds that cumulative wear into your dimension. A worn 171.45 mm (6.75 in) chain stretched by +3.5 mm/link measures 175.0 mm per link—matching the nominal pitch of an entirely different 175.0 mm (Komatsu PC100-5 / Hitachi EX200-1) chain whose bushings will jam on a 171.45 mm drive sprocket within half a revolution.
3. Sub-Series revisions Shift Track Shoe Bolt Diameters (M18 vs. M20 vs. M22) and Bolt-Hole Gauges (D x E x B): Even when both nominal pitch (190.0 mm) and link count (45L or 46L) match, OEMs revise the forged link's top mounting pad across series breaks. For example, a Komatsu PC200-3 (Berco KM1170) uses an 18.3 mm (M18 x 1.5) track shoe bolt hole, whereas a Komatsu PC200-5/6/7/8 (Berco KM782, OEM 20Y-32-00014), CAT 320 (Berco CR5350, OEM 9W9354), and SANY SY215C use a 20.3 mm (M20 x 1.5) bolt hole. If you order a bare track chain intending to transfer your existing 600 mm triple-grouser shoes, an unverified bolt-hole or gauge shift stops assembly cold.

Step-by-Step Field Metrology Protocol (Coordinates 1 to 6)

Before submitting a request through our undercarriage parts catalog or quote request form, record these six physical measurements in millimeters (mm):

1. Coordinate 1 — 4-Link Pitch Span (L_4-link in mm -> P_nom = L_4-link / 4): Roll the excavator forward 1 to 2 meters on level ground and let it coast to a stop without braking so the upper and lower track spans are pulled taut in forward drive contact (eliminating slack between pins and bushings). Using a rigid steel millimeter tape measure, hook or align the zero mark on the exact center (or left outer edge) of Pin 1, count four complete link sections (skipping Pins 2, 3, and 4), and read the distance to the exact same reference point (center or left outer edge) on Pin 5. Divide that 4-link measurement by 4 (or if measuring from Pin 1 to Pin 4 across 3 link sections, divide by 3) and match it against the standard nominal pitch baseline (135.0 mm, 154.0 mm, 171.45 mm, 175.0 mm, 190.0 mm, 203.2 mm, 215.9 mm, 228.6 mm, 260.0 mm).
2. Coordinate 2 — Total Link / Pitch Section Count (N_links per Side): Locate the Master Pin / Master Link (identifiable by a recessed center dimple, chamfered pin ends, locking collar, or diagonal split across the link forging) and mark it with high-visibility paint or soapstone chalk (Link #1). Walk around the entire perimeter of the track—over the carrier rollers, around the front idler, under the bottom track rollers, and around the final drive sprocket—marking every 5th link (#5, #10, #15...) until you return to Link #1. Never count only the top half and multiply by two; always count every single pitch section (e.g., 45L, 46L, 47L, 48L, 49L, 51L).
3. Coordinate 3 — Forged Link Stamped Casting / Part Number (OEM / Berco / ITM Code): Wire-brush the recessed web on the side of two or three standard links and the master link. Photograph the raised forging characters under 10 to 25 deg raking light following our part photography guide. A single stamped forging code—such as CR5350, KM782, KM959, KM2233, 20Y-32-00110, or 9W9354—immediately locks the link geometry, rail height, and shoe bolt pattern.
4. Coordinate 4 — Bushing Outer Diameter (D_b) & Pin Diameter (d_pin): Using a stainless vernier caliper (+/- 0.1 mm) or ultrasonic undercarriage gauge, measure the Track Bushing OD (D_b) at the unworn outer edge next to the link boss (away from the center sprocket-contact zone) and measure the Track Pin OD (d_pin) where visible at the master pin or outer link boss. On a standard 190.0 mm pitch 20-ton excavator chain (Komatsu 20Y-32-00014 / CAT 320 / SANY SY215C), new standard values are D_b = 59.3 mm and d_pin = 38.2 mm.
5. Coordinate 5 — Inner & Outer Link Rail Width (W_rail,in / W_rail,out) & Link Height (H_link): Measure the inside clearance width (W_rail,in) between the left-hand and right-hand forged links where the center guide flanges of the bottom rollers and front idler ride (typically 80 to 86 mm on 190 mm pitch), the outside width across both link rails (W_rail,out, typically 164 to 170 mm), and the vertical Link Height (H_link) from the flat shoe-bolting surface to the roller-running rail surface (new H_link = 104.0 to 105.0 mm on 190 mm excavator links; 122.0 to 133.0 mm on 215.9 mm links).
6. Coordinate 6 — Track Shoe 4-Bolt Pattern (D, E, B in mm), Bolt Diameter (L), and Shoe Width (W_shoe): Because forged excavator links are offset (narrower at the bushing end, wider at the pin counterbore end), the 4 bolt holes form a symmetric trapezoid across each pair of links. Measure:
   • Dimension D (Outer / Wide Transverse Bolt Spacing, mm): Center-to-center distance across the two wider-spaced bolt holes (160.0 mm on standard 190 mm pitch).
   • Dimension E (Inner / Narrow Transverse Bolt Spacing, mm): Center-to-center distance across the two narrower-spaced bolt holes (125.0 mm on standard 190 mm pitch).
   • Dimension B (Longitudinal Bolt Spacing, mm): Center-to-center distance between the two bolt holes along the length of a single link (65.0 mm on standard 190 mm pitch).
   • Dimension L (Track Bolt Hole / Shank Diameter, mm) & Shoe Width (W_shoe, mm): Measure the bolt shank diameter (M16 = 16.0 mm, M18 = 18.0 mm, M20 = 20.0 mm, M22 = 22.0 mm, M24 = 24.0 mm) and overall track shoe width (e.g., 500 mm, 600 mm, 700 mm, 800 mm).

Engineering Rule-of-Thumb (4-Consecutive-Pin Tape Measurement P_nom = L_4-link / 4 vs. Single-Link Stretch Over-Reading Threshold): When identifying the nominal pitch (P_nom) of a worn track chain on the machine → never measure across a single link (1-pitch span) where 2.5 to 4.5 mm of internal pin-and-bushing radial clearance is concentrated; always pull the chain taut in forward travel, measure center-to-center across 4 consecutive link pitches (5 pins, Pin 1 center to Pin 5 center), and divide by 4 (P_meas = L_4-link / 4), because measuring a single stretched link over-reads a worn 190.0 mm chain as 193 to 196 mm (or a worn 171.45 mm chain as 175.0 mm), causing buyers to misorder a 203.2 mm or 175.0 mm track chain that cannot mesh with the drive sprocket tooth pitch circle.

Engineering Rule-of-Thumb (Physical Full-Loop Link Count N_links Chalk-Mark Verification vs. Cab Model Decal Threshold): Before approving any excavator track chain order → chalk-mark the master pin as Link #1 and physically count every individual link section (N_links) around the full track loop rather than relying on the cab model decal (e.g., "CAT 320", "SANY SY215", "Komatsu PC200", or "Kobelco SK200"), because the exact same 20-ton excavator model ships with 45 links on a Standard (STD) undercarriage frame, 46 links on intermediate frames, 49 links on a Long Crawler (LC / NLC) frame, or 51 to 52 links on Super Long Reach (SLR) frames—and a 4-link error (760 mm) renders a 900 kg steel chain impossible to install.

---

2. OEM Excavator Track Chain Pitch Classes (135 mm to 260 mm) & Cross-Brand Reference Matrix

Standard crawler excavator steel track link assemblies are engineered around eight standardized metric/imperial pitch families (135.0 mm to 260.0+ mm). Use the reference matrix below as an engineering baseline under standard factory configurations, and always verify your specific serial break (ISO 10261 PIN) and physical link count (N_links) before ordering:

---

3. Joint Sealing (Dry vs. Sealed & Greased vs. Oil SALT) & Master Link Architecture

Not all track chains that share the same 190.0 mm or 215.9 mm pitch are constructed the same internally. Before comparing supplier quotes, verify both the internal pin-to-bushing sealing design and the master joint closure method:

---

4. Quantitative Engineering Sizing: 4-Pin Pitch Wear Percentage (Wear_%), Loop Elongation (Delta_L), and Sprocket Pitch-Circle Mismatch

Never guess whether an existing track chain or drive sprocket can be reused, and never accept a single-link caliper reading as nominal pitch. Use the three engineering equations below to calculate exact nominal pitch, percentage internal wear consumed, track adjuster stroke margin, and sprocket-to-chain mismatch cost:

Equation 1: 4-Link Nominal Pitch (P_meas) & Internal Pin/Bushing Wear Percentage (Wear_%)

When you measure center-to-center across 4 consecutive link pitches (Pin 1 to Pin 5) under tension (L_4-link,measured in mm), the average measured pitch per link (P_meas) and the percentage of internal pin-and-bushing wear life consumed (Wear_%) relative to the OEM 0% new span (4 * P_nom) and 100% service wear limit (L_4-link,100%) are governed by:

P_meas [mm]  = L_4-link,measured [mm] / 4
Wear_% [%]   = ( (L_4-link,measured - (4 * P_nom)) / (L_4-link,100% - (4 * P_nom)) ) * 100%
Life_rem [%] = 100% - Wear_%

• 1-Line Worked Example (20-Ton Excavator 190.0 mm Pitch Chain Internal Wear Audit — CAT 320 / Komatsu PC200 / SANY SY215C): Given a nominal pitch P_nom = 190.0 mm (new 4-link span = 4 * 190.0 = 760.0 mm), an OEM 100% internal wear limit of L_4-link,100% = 772.0 mm (+3.0 mm internal radial wear per link), and a field tape measurement across 4 links of L_4-link,measured = 769.6 mm:

  P_meas = 769.6 / 4 = 192.40 mm/link   -->   Wear_% = ((769.6 - 760.0) / (772.0 - 760.0)) * 100% = (9.6 / 12.0) * 100% = 80.0% Worn (20.0% life remaining — schedule chain & sprocket replacement)
  

Equation 2: Total Unrolled Track Chain Length (L_chain) & Track Adjuster Idler Stroke (Delta_S_idler)

For a track chain with N_links total pitch sections, the total unrolled loop length (L_chain in mm), cumulative loop elongation (Delta_L_loop in mm), and the forward stroke required at the front idler grease tensioner cylinder (Delta_S_idler in mm, which takes up two parallel horizontal track spans—top and bottom) follow:

L_chain [mm]       = N_links * P_meas [mm]
Delta_L_loop [mm]  = N_links * (P_meas - P_nom)
Delta_S_idler [mm] = Delta_L_loop / 2 = ( N_links * (P_meas - P_nom) ) / 2

• 1-Line Worked Example (Why a 49-Link SANY SY215C / Kobelco SK200-8 Chain Bottoms Out the Idler Adjuster at 100% Wear — and Why Cutting Out 1 Link Fails): On a 49-link (N_links = 49) 190.0 mm chain (new length L_chain,0% = 49 * 190.0 = 9,310.0 mm), when internal wear reaches +3.0 mm/link (P_meas = 193.0 mm):

  L_chain,100% = 49 * 193.0 = 9,457.0 mm  -->  Delta_L_loop = +147.0 mm  -->  Delta_S_idler = 147.0 / 2 = +73.5 mm forward idler stroke (Cutting 1 link removes 193.0 mm, leaving only +147 - 193 = -46 mm slack, while the 193.0 mm pitch still climbs the 190.0 mm sprocket teeth!)
  

Equation 3: Drive Sprocket Pitch-Circle Diameter Mismatch (Delta_D_pitch) & Accelerated New-Chain Cost Penalty (Cost_per_hour)

A drive sprocket with Z_s teeth meshing with a chain of pitch P operates on a kinematic pitch-circle diameter D_pitch = P / sin(180 deg / Z_s). When a brand-new chain (P_nom) is installed onto a worn sprocket whose tooth drive faces have hooked to match an old stretched chain (P_worn), the pitch-circle diameter mismatch (Delta_D_pitch in mm) and hourly chain ownership cost (Cost_per_hour = C_chain / L_hours) follow:

D_pitch [mm]         = P [mm] / sin(180 deg / Z_s)
Delta_D_pitch [mm]   = (P_worn - P_nom) / sin(180 deg / Z_s)
Cost_per_hour [$/h]  = C_chain_pair [$] / Service_Life [hours]

• 1-Line Worked Example (Installing a $3,800 Pair of New 190.0 mm Chains onto Worn 21-Tooth Sprockets vs. Adding $760 for 2 New Sprockets): Given a Z_s = 21-tooth sprocket (sin(180/21) = sin(8.5714 deg) = 0.14904) worn to P_worn = 193.0 mm vs. a new P_nom = 190.0 mm chain (pair cost C_chain = $3,800, rated life 4,500 hours with new sprockets vs. 1,500 hours on hooked sprockets):

  Delta_D_pitch = (193.0 - 190.0) / 0.14904 = +20.13 mm pitch-circle mismatch  -->  Hourly Cost jumps from ($3,800 / 4,500 h = $0.84/h) to ($3,800 / 1,500 h = $2.53/h), destroying $2,533 of track chain life to "save" $760 on two new drive sprockets!
  

Engineering Rule-of-Thumb (Never Install a New 0% Wear Track Chain Onto a Drive Sprocket With > 30%–40% Hooked Tooth Wear Threshold): Whenever you install a new replacement track link assembly (0% wear, P = P_nom) → always replace the bolted track drive sprockets simultaneously if the existing sprocket teeth exhibit > 30% to 40% profile wear or visible tip hooking/pointing, because a sprocket worn by an elongated old chain (P_worn = 193.0 mm) has a +20.1 mm pitch-circle diameter mismatch against a new 190.0 mm chain, concentrating the excavator's full 180 to 240 kN tractive drawbar pull onto a single sprocket tooth tip, stripping the outer carburized case (HRC 58–62) off the new chain bushings in < 200 to 300 operating hours, and cutting total chain life by 50% to 65%.

---

5. Track Shoe 4-Bolt Pattern Metrology & ISO 898-1 Property Class 12.9 Torque-Plus-Turn Protocol

Whether you order a Bare Track Link Assembly (to transfer your existing triple-grouser track shoes) or a Pre-Bolted Complete Track Group (chain + shoes factory-torqued), the track shoe bolted joint is the highest-stressed fastener interface on a crawler excavator. Every time the excavator pivots in blasted rock or climbs a stockpile, the grouser tips apply massive prying and bending moments directly against the four track bolts securing each shoe to its left-hand and right-hand forged links.

Standard ISO 898-1 Property Class 12.9 Track Shoe Bolt Torque & Torque-Turn (T_pre + 120 deg) Matrix

Standard commercial hardware store bolts (Class 8.8 or Class 10.9 coarse thread) will stretch and shear within hours on an excavator track chain. Undercarriage track bolts are cold-forged from 40Cr / 35CrMo / 42CrMo alloy steel quenched and tempered to ISO 898-1 Property Class 12.9 (nominal tensile strength R_m = 1,220 MPa, yield strength R_p0.2 = 1,100 MPa, core hardness HRC 39–44) with a dome/countersunk collar head, metric fine thread (1.5 mm pitch) to resist vibration self-loosening, and an induction-hardened square track nut that locks rotationally inside the forged link window:

Engineering Rule-of-Thumb (ISO 898-1 Property Class 12.9 Track Shoe Bolt Torque-Plus-Turn T_pre + 120 deg on Bare Paint-Free Mating Faces Threshold): Whenever bolting existing or new triple-grouser track shoes onto a replacement track link assembly → discard all old bolts/nuts, wire-brush or disc-grind both the forged link top bolting pad and the track shoe bottom mating ribs down to bare paint-free steel, lubricate the bolt threads and under-head fillet with light machine oil or anti-seize, seat the square nut flat side against the forged link window, and tighten new ISO 898-1 Property Class 12.9 (HRC 39–44, 1,220 MPa) fine-thread bolts using the 2-stage Torque-Plus-Turn method (e.g., 175 N*m + 120 deg for M16x1.5, 430 N*m + 120 deg for M20x1.5, 500 N*m + 120 deg for M22x1.5, or 515 N*m + 120 deg for M24) in a criss-cross diagonal sequence, because trapped primer paint (150–300 um) or dry-thread friction causes conventional torque wrenches to click out prematurely, allowing the shoe to fret and shear all four bolts within 50 to 150 operating hours.

---

6. Supply-Scope Envelope Matrix: Bare Track Link Assembly vs. Complete Bolted Track Group

In our undercarriage parts catalog, suppliers and buyers use three distinct ISO 8000-110 units of measure (Piece, Bare Track Chain Assembly, and Complete Bolted Track Group). Always specify which delivery envelope you want quoted—and separate companion rollers, idlers, and sprockets onto their own line items:

---

7. 5-Year Excavator Track Chain Fitment, Worn-Sprocket Cascade & Undercarriage TCO Ledger

The undercarriage accounts for up to 50% of a tracked excavator's lifetime maintenance cost. Skipping the 6-dimension checklist or mating a new chain to worn companion components triggers immediate financial losses across five hidden TCO drivers:

---

8. Frequently Asked Questions About Excavator Track Chain Fitment & Replacement

How do I know what size track chain my excavator takes if the part number is rusted off?

Never measure a single worn link and never rely on machine tonnage alone. Instead, follow a four-step physical measurement sequence on the machine:

1. Pull the chain taut in forward travel to measure the 4-Link Pitch (P_nom = L_4-link / 4) from the center of Pin 1 to the center of Pin 5 (4 link sections) with a millimeter steel tape, divide by 4, and match the result to the nearest standard nominal pitch (135.0 mm, 154.0 mm, 171.45 mm, 175.0 mm, 190.0 mm, 203.2 mm, 215.9 mm, 228.6 mm, or 260.0 mm).
2. Chalk-mark the master pin as #1 and count the Total Links (N_links) around one complete track loop (e.g., 45, 46, 47, 48, 49, or 51 links).
3. Clamp a vernier caliper across the unworn end of a track bushing to record the Bushing OD (D_b, e.g., 59.3 mm on a 190 mm chain) and measure the Inner Rail Width (W_rail,in) that straddles the roller flanges.
4. Measure the 4-Bolt Shoe Grid (D, E, B & Bolt Size L)—recording the outer transverse bolt spacing (D), inner transverse bolt spacing (E), longitudinal spacing (B), and bolt shank diameter (M16, M18, M20, M22, M24)—and send all six figures with your machine's ISO 10261 serial plate photo via our Request a Quote page.

Can I shorten a loose excavator track chain by removing one link instead of buying a new chain?

Cutting out one link ("dropping a link") is a destructive field shortcut that accelerates sprocket and final drive failure. A track chain becomes loose and bottoms out the front idler adjuster because internal pin-and-bushing wear has elongated every single pitch section (for example, from 190.0 mm new to 193.5 mm worn). Removing one link shortens the overall loop circumference by 193.5 mm so the front idler retracts back into the frame, but every one of the remaining 44 or 48 links still has a 193.5 mm elongated pitch. That 3.5 mm/link mismatch (+23.5 mm pitch-circle diameter error on the sprocket) forces the chain bushings to ride high up on the tips of the drive sprocket teeth under extreme tension, rapidly snapping sprocket teeth, cracking bushings, and overloading the final drive planetary hub bearings.

Should I order bare track chains (link assemblies) or complete bolted track groups (with shoes)?

Choose Bare Track Link Assemblies (Scope Envelope 2) only when your existing triple-grouser track shoes retain >= 50% to 60% of their original grouser bar height, have flat unbent plates, and have round, un-wallowed bolt holes—and always budget for 100% new ISO 898-1 Property Class 12.9 track bolts and square nuts (never reuse old bolts). Choose Pre-Bolted Complete Track Groups (Scope Envelope 3) whenever your existing grousers are worn down near the bolt heads, any shoes are bent or cracked, or when workshop labor rates (16 to 24 hours to torch-cut and torque 360 to 400 track bolts) exceed the price difference of factory-torqued track groups.

Are Left (LH) and Right (RH) excavator track chains different?

Each individual forged track link inside a chain is handed—every pitch section consists of one Left-Hand (LH) offset link and one Right-Hand (RH) offset link pressed onto a shared pin and bushing. However, once assembled into a complete Track Link Assembly (Bare Chain) or Complete Track Group, the Left track assembly and Right track assembly on the excavator are identical part numbers (you order Quantity = 2 identical chain assemblies per machine). The only directional requirement occurs during installation on the machine: the narrow (bushing) end of the offset links must lead in the forward travel direction toward the front idler (and the triple-grouser overlap lip must face the correct direction) so the drive sprocket teeth contact the bushing properly during forward travel.

---

What to Send Us to Verify Your Excavator Track Chain Before Quotation

When you are ready to source replacement track chains, complete track groups, track shoes, Class 12.9 hardware, or companion rollers, idlers, and sprockets via our Request a Quote page, include the five verification items below:

---

Copy the Excavator Track Chain 6-Dimension Fitment & Scope Verification Worksheet

Copy the editable worksheet below, fill in the measurements taken from your excavator serial plate and existing track chain, and leave any unmeasured field marked as Unknown — verify before ordering. Paste the completed worksheet into our quote request form along with your machine nameplate and link forging photos, or browse our undercarriage parts, final drives, travel motors, hydraulic cylinders, and seal kits.

---

Method and Sources

This engineering fitment guide and 6-dimension undercarriage verification checklist were compiled and verified in October 2026 by the HeavyPartsSource undercarriage and drivetrain engineering team using international metallurgy, fastener, and machine-identification standards alongside OEM and tier-1 undercarriage manufacturer technical documentation:

1. ISO 683-1 / EN 10083-3 (Heat-Treatable Boron & Cr-Mo Alloy Steels) & Tier-1 Undercarriage Metallurgy Baselines — Forged 35MnB / 40Mn2 track links (HRC 32–38 core, HRC 52–58 induction-hardened rail surface with 8–12 mm case depth), 20CrMnTi carburized bushings (HRC 58–62), 40Cr / 42CrMo4 induction-hardened track pins, and 25MnB rolled triple-grouser track shoes (HRC 42–49) (cliktracks-sealed-greased-excavator-chains.txt, feiyueparts-190mm-pc200-cat320-track-link.txt, oem-excavator-track-chain-standards-and-specs.md).
2. Berco (MT24, KM906, KM1686, KM965, CR4854, CR1766, KM1262, HT420, CR5350, CR5011, KM782, KM1170, CR5489, KM959, KM1617, CR5936, KM2233, KM1402, KM973, KM2489, KM596), Caterpillar (9W9354, 6Y8184, 6Y0854, 6Y2755), Komatsu (201-32-00131, 203-32-00101, 20Y-32-00013 / 20Y-32-00014, 207-32-00101, 207-32-00300, 208-32-00300), Hitachi, Kobelco, Hyundai, and SANY (SY135C 44L, SY215C 49L, SY365H 13912646) Cross-Reference Data — Nominal pitch classes (135.0 mm to 280.0 mm), STD vs. LC link counts (37L to 53L), bushing/pin diameters (59.3 mm / 38.2 mm on 190 mm pitch), and 4-bolt shoe grid dimensions (160 / 125 x 65 mm) (cliktracks-sealed-greased-excavator-chains.txt, bestpartscn-berco-excavator-track-chain-cross-ref.txt, feiyueparts-190mm-pc200-cat320-track-link.txt, astrak-sany-sy215-track-chain-specs.txt).
3. ISO 898-1 Property Class 12.9 / SAE J429 / JIS B 1180 Fastener Standards & West-Trak / ITR Track Bolt Torque-Turn Specifications — High-tensile 1,220 MPa (HRC 39–44) fine-thread track shoe plow bolts (M14x1.5 to M24x1.5/2.0), Method A conventional lubricated torque (370 to 1,270 N*m), and Method B 2-stage Torque-Plus-Turn (T_pre + 120 deg) tightening protocol (oem-excavator-track-chain-standards-and-specs.md, tkv-excavator-steel-tracks-chains.txt).
4. Heavy Vehicle Inspection (HVI, How to Inspect Heavy Equipment Undercarriage Wear) & VemaTrack (Recognising Wear on Your Undercarriage Parts) — 4-pin tape pitch elongation measurement, percentage wear formula, tandem sprocket-and-chain replacement rules, seized bottom roller cascade mechanics, 50 mm (2 in) track sag targets, and 250 / 500–1,000 hour inspection intervals (hvi-track-undercarriage-wear-inspection.txt, vematrack-undercarriage-wear-guide.txt).
5. TKV Australia (Excavator Steel Tracks & Chains) & MechLink (Track Chain Types: Dry and Lubricated) + ISO 10261:2021 & ISO 8000-110 — Sealed and greased polyurethane-sealed excavator chains versus dry unsealed (UNS) and vacuum oil-lubricated (SALT) chains with split alligator master links, plus Piece vs. Bare Chain vs. Complete Track Group procurement scope separation (tkv-excavator-steel-tracks-chains.txt, mechandlink-dry-and-lubricated-track-chains.txt, hps-undercarriage-category.txt, iso-10261-preview.txt).