Volvo EC20 ミニエキスカベータのためのNachi PHV-2B MAG18VP-220 ファイナルドライブ

EC20 Final Drive for Excavator spare parts PHV‑2B MAG18VP‑220 Axial Piston Motor OEM

Product Overview

On a compact excavator like the Volvo EC20, almost every working minute ends with a pivot: dig, swing, reposition, crawl a metre, pivot again. That constant low‑speed, high‑torque work is the final drive's whole life — the axial piston motor and planetary reduction under each track that turns hydraulic flow into sprocket rotation. The units carrying references PHV‑2B and MAG18VP‑220 are built for exactly this duty cycle, but thousands of tiny manoeuvres still wear them down. The first sign is rarely dramatic: the tracks do not quite match speed, the machine drifts instead of rolling dead straight, and after a longer run the drive housing feels warmer than usual. Left that way, the gap between tracks widens until one side hesitates under load. By then the piston group and reduction gears are already scoring against each other. This OEM‑grade drive is built as one matched motor‑and‑reduction assembly, so the worn unit can be unbolted and replaced in a single swap — no mixing parts across a cramped undercarriage.

Core Advantages

1. Piston internals that keep pressure where it belongs
The motor's piston, cylinder block and valve plate are finished to tight clearances, so hydraulic pressure does not leak away inside the unit. The payoff is even pull from both tracks — no crab‑walking, no slow side, no hesitation the moment the bucket loads up.

2. Reduction gears engineered for a mini machine's pivot cycles
Mini excavators reverse and reposition hundreds of times a shift. Hardened planetary gears with controlled backlash absorb that daily reversing load smoothly and quietly, without the click or grind that tells you the gear teeth are being hammered.

3. Seal protection for low‑to‑the‑ground working conditions
A compact drive sits close to mud, puddles and fine dust. The fitted shaft and housing seals hold the line against that contamination, keeping grit out of the motor and gear oil — the main reason these drives survive or fail early.

4. Arrives as one tested unit, ready to fit
Motor and gearbox come pre‑assembled and bench‑checked, so the fitter removes the old drive and bolts on the new one without having to source or mate separate components. On a mini undercarriage, that straightforward swap is a real time‑saver.

5. OEM‑spec build without the dealer price
An original Volvo final drive exchange is hard to justify on a small, well‑used machine. This OEM‑grade unit matches the original fit and performance at a far more practical cost, with sample and batch supply available.

Manufacturing & Quality Control

Every drive is built to controlled specifications: incoming material verification, precision machining of housings and gear components, case hardening of wear surfaces and clean assembly. Before packing, each unit runs on a test rig to verify output torque, internal leakage and operating noise; anything outside acceptance limits is rejected. Completed drives are preservation‑coated, sealed against moisture and packed in shock‑absorbing export casing.

Frequently Asked Questions

Q1: How do I confirm these references match my machine?
A: Check the nameplate on your existing drive against PHV‑2B and MAG18VP‑220, and send us the machine serial number. Compact Volvo build variants can differ, so we confirm before dispatch.

Q2: Does this come ready to install?
A: Yes — the motor and reduction are supplied as one complete, tested assembly with seals fitted. After bolting it on, bleed the travel circuit and check oil level before use.

Q3: What faults suggest the drive is wearing out?
A: Mismatched track speeds, drifting on flat ground, a warm or noisy track motor and hesitation under load. Catch it early and the damage stays inside the drive; leave it and contamination spreads.

Q4: What does the warranty cover?
A: Material and workmanship defects are covered. Damage from contaminated oil, debris entering the motor, track obstruction, overload or incorrect fitting is excluded — follow the Volvo service manual for installation.