- ADDRESS：Wanda Plaza, Jinan, Shandong, China
- Wanda Plaza, Jinan, Shandong, China
- +8617615809553
- info@deruna.com
Precision-engineered piston ring assembly for high-performance diesel engines – The OEM A6000-1004040A#4 Piston Ring Assembly is designed to deliver perfect cylinder sealing, minimal blow-by, and exceptional oil control. Manufactured from ductile cast iron and steel, with advanced coatings, this set ensures optimal compression and reduced emissions. For guaranteed compatibility and performance, always choose genuine Sinotruk Homan parts. The A6000-1004040A#4 ring set includes a plasma-moly coated top ring, a tapered second ring, and a three-piece oil ring assembly for maximum durability and oil economy.
The A6000-1004040A#4 piston ring assembly is the result of decades of tribological engineering. The three‑ring configuration (top, second, oil) works in harmony to seal combustion gases, control oil consumption, and transfer heat from the piston to the cylinder wall.
The top compression ring is made of high‑strength ductile iron and coated with a plasma‑sprayed molybdenum layer, which retains oil and resists scuffing even under high cylinder pressures. The barrel‑faced profile ensures rapid conformability during break‑in.
The second ring features a taper‑face design with a Napier hook (scraper edge) that actively scrapes oil downward, reducing oil consumption by up to 30% compared to straight‑face rings. The three‑piece oil ring assembly includes two steel rails and an expander spacer, providing constant radial pressure and excellent conformability to worn cylinder bores.
Sprayed molybdenum coating (0.25mm) provides excellent scuff resistance, micro‑oil reservoirs, and reduced friction during the critical break‑in period.
Tapered face with a sharp bottom edge actively scrapes oil from the cylinder wall, reducing oil consumption and preventing carbon buildup in the groove.
Two chrome‑plated steel rails and a stainless steel expander provide uniform wall pressure, excellent oil control, and resistance to plugging.
| OEM Number | A6000-1004040A#4 |
| Product Name | Piston Ring Assembly (Set of 6 cylinders, 3 rings per piston) |
| Brand | SINOTRUK Homan |
| Top Ring Material | Ductile cast iron (Grade 65‑45‑12) + plasma moly coating |
| Second Ring Material | Gray cast iron (Grade 30) with phosphate coating, Napier hook |
| Oil Ring Material | Steel rails (SAE 1070 chrome plated) + stainless steel expander |
| Cylinder Bore Diameter | 110.00 mm (nominal) – fits SINOTRUK A6000 engine |
| Top Ring Width | 3.00 mm ±0.005 mm |
| Second Ring Width | 2.50 mm ±0.005 mm |
| Oil Ring Width (per rail) | 4.00 mm (total assembly height) |
| Top Ring Coating Hardness | Mo layer 300‑400 HV, base material 250 HB |
| Oil Ring Rail Coating | Hard chromium (5‑10 microns, 700‑800 HV) |
| Max Operating Temperature | Top ring groove 250°C continuous |
| Applicable Engines | SINOTRUK Homan A6000 series, D10, D12, WD615 (with specific bore) |
| Manufacturing Process | Precision casting, CNC turning, plasma spray, chrome plating, 100% optical inspection |
| Standards | IATF 16949, ISO 9001, SAE J1264 |
The A6000-1004040A#4 ring set is engineered using advanced simulation tools to optimize ring dynamics, minimizing flutter at high RPM and ensuring conformability to bore distortions. The top ring features a slight barrel face (crown radius 250mm) that ensures line contact even when the piston tilts, promoting rapid sealing.
The molybdenum coating is applied via plasma transfer arc (PTA), creating a porous structure that holds oil and acts as a solid lubricant during cold starts. This coating also reduces scuffing when cylinder wall lubrication is marginal.
The second ring’s Napier hook (a sharp undercut on the bottom edge) creates a hydrodynamic scraper action that directs oil back to the crankcase. Together with the oil ring, this assembly achieves oil consumption below 0.05% of fuel consumption in a well‑maintained engine.
Conventional cast iron rings wear quickly in modern high‑boost diesel engines. The plasma moly coating on the top ring A6000-1004040A#4 provides a “sacrificial” layer that wears in initially, creating a perfectly matched surface to the cylinder bore without damaging the liner. After break‑in, the hard iron substrate behind the moly provides long‑term wear resistance.
The oil ring rails are hard‑chrome plated, offering excellent corrosion resistance against acidic combustion byproducts and reduced friction against the cylinder liner. This prolongs oil ring life and maintains consistent oil control over thousands of hours.
Engine dynamometer tests comparing the A6000-1004040A#4 with basic grey iron rings showed a 45% reduction in blow‑by (from 30 L/min to 16 L/min at full load). Lower blow‑by reduces crankcase pressure, extends oil life, and lowers emissions. Additionally, the lower ring tension (optimized for fuel efficiency without compromising oil control) improved fuel economy by 1.5% in highway cycle testing.
Correct installation is essential for ring performance and longevity. Follow these steps: 1) Verify cylinder bore is within wear limits (max taper 0.05mm, ovality 0.03mm). 2) Hone the cylinder with a plateau finish (Ra 0.25‑0.45μm) to promote ring break‑in.
3) Clean ring grooves in the piston thoroughly; remove all carbon. 4) Check ring end gap before installation: top ring 0.35‑0.45mm, second ring 0.55‑0.65mm, oil ring 0.25‑0.50mm. File ends if needed (only if oversize).
5) Install rings starting from oil ring: expander first, then lower rail, then upper rail. Stagger rail gaps 180° apart. 6) Install second ring with tapered face (mark “TOP” or dot facing upward). 7) Install top ring with moly face up, barrel profile. 8) Stagger ring gaps 120° apart, never align gaps.
9) Lubricate rings and piston with clean engine oil. 10) Use a band‑type ring compressor; never use tapered clamps. 11) Insert piston into bore with gentle tapping; do not force.
After installing the A6000-1004040A#4 rings, perform a break‑in procedure: vary engine speed and load for the first 5 hours, avoid prolonged idle. Use mineral‑based oil for break‑in (if possible), then change to full synthetic after 100 hours.
Monitor blow‑by with a manometer; if blow‑by increases sharply, check for broken rings or bore wear. Oil consumption should stabilize below 0.1% of fuel consumption. If oil consumption remains high after 200 hours, inspect ring orientation and cylinder bore finish.
The A6000-1004040A#4 piston ring assembly is manufactured in an IATF 16949 certified facility. Each batch undergoes: (a) chemical analysis (spectrometry), (b) hardness testing (Vickers), (c) coating thickness measurement (eddy current), (d) 100% ring gap inspection using laser gauges, (e) axial twist testing.
Sample rings from each batch are installed in a single‑cylinder test engine and run for 500 hours under full load. Blow‑by and oil consumption are continuously monitored. Additionally, rings are subjected to thermal shock testing (rapid cycling from 50°C to 300°C) with no coating delamination.
SINOTRUK Homan provides a certificate of conformance with each set, including measured ring gap values.
A logistics fleet of 500 SINOTRUK A6000 trucks replaced old ring sets with the A6000-1004040A#4 assembly. After 400,000 km, oil consumption averaged 0.08 L per 1000 km, compared to 0.25 L with previous rings. Blow‑by readings remained within new engine limits, eliminating the need for mid‑life overhauls.
Another case: a construction company with D12 engines operating in dusty conditions reported that genuine SINOTRUK Homan ring sets lasted twice as long as aftermarket alternatives, reducing downtime by 60%. The plasma moly coating prevented scuffing even when air filter maintenance was delayed.
Each genuine A6000-1004040A#4 piston ring assembly is supplied in a color‑coded plastic box with compartments for each cylinder’s rings. The box includes a hologram sticker with a unique QR code. Scanning the QR code redirects to the SINOTRUK Homan verification portal.
The rings themselves are laser‑etched with the OEM number and “SINOTRUK” on the top ring face. Counterfeit rings often have inconsistent coating, wrong gap sizes, or no heat‑treatment markings. Always purchase from authorized distributors to guarantee genuine quality and performance.
Summary: The SINOTRUK Homan Piston Ring Assembly (OEM A6000-1004040A#4) delivers exceptional compression, oil control, and durability for A6000 series diesel engines. Upgrade to genuine OEM for maximum efficiency and engine longevity.
If you have any questions about our products, services, or anything related to what we offer, please don’t hesitate to leave us a message—our dedicated team is always ready to provide prompt and helpful responses to address your concerns. What’s more, when you become our valued customer, we’re delighted to offer you complimentary catalog services, giving you access to detailed, up-to-date information on our full range of products, specifications, and offerings to help you make informed decisions.
We are a first-class heavy duty vehicles and spare parts supplier in China. which covers from engine, gearbox, cab, axle assemblies to main assembly accessories, electrical parts and other chassis parts like brake, clutch and steering parts.
A PROFESSIONAL CHINA TRUCK AND SPARE PARTS SUPPLIER
@Copyright DERUNA
