• 6137-31-2200 6137-31-2032 6137-31-2031 Piston Ring Assy KOMATSU Excavator Spare Parts For S4D105-5B

• Specifiion

• Key functions of each ring

1Top Compression Ring:
Seals 70–80% of combustion pressure (up to 10 MPa) between the piston and cylinder liner, preventing high-pressure gases from leaking into the crankCAASE. Its molybdenum coating reduces friction and withstands extreme heat from combustion.

2.Secondary Compression Ring:
Reinforces the seal, capturing residual gas leakage past the top ring. It also acts as a backup for heat transfer (dissipates ~20% of piston heat to the cylinder liner).

3.Oil Control Ring:
Scrapes excess oil from the cylinder liner walls during the piston’s downward stroke, preventing oil from entering the combustion chamber (which causes smoke and carbon buildup). Its spring-loaded design ensures consistent contact with the liner, even as components wear.

• Compatible models

• More other piston ring assy parts fit for KOMATSU machine

• alog parts list

• We could supply the following spare parts

1 Hydraulic parts: hydraulic pump, main valve, hydraulic cylinder, final drive, travel motor, swing machinery, swing motor etc.

2 Engine parts: engine ass’y, piston, piston ring, cylinder block, cylinder head, crankshaft, turbocharger, fuel injection pump, starting motor and alternator etc.

3 Undercarriage part: Track roller, Carrier roller, Track Link, Track shoe, Sprocket, Idler and Idler cushion etc.

4 Cab parts: operator’s cab, wiring harness, monitor, controller, seat, door etc.

5 Cooling parts: Radiator, air conditioner, compressor, after cooler etc.

6 Other parts: Service kit, swing circle, engine hood, swing joint, fuel tank, filter, boom, arm, bucket etc.

• Advantage

1. Offer Top quality & competitive products

2. Support 12-month warranty

3. 100% tested before shipping

4. Delivery in time

5. A wide range of Oil Pressure Sensor, Fuel Tank Level Sensor, Temperature Sensor, Speed Sensor for excavator 

6. More than 15 years production and 11 years foreign trade experience

7. Professional QC team

8. Best sales team, 24 hours service

• Packing and Shipping

Packing Details :

inner packing : plastic film for wrapping

external packing : wooden

Shipping :

within 3 days after received the payment , by air or by express or by sea on the basis of the

quantity and emergency circumstances.

1. By Couriers: DHL, UPS, FEDEX, TNT are the main courier companies we are cooperated,

2. By Air: Delivery from the Guangzhou air port to customer's destination city air port.

3. By Sea: Delivery from the Huangpu port .