EPG Heavy‑load Plastic Bearings Empower Sweeping‑brush Systems of Sanitation Road Sweepers: 3‑fold Service‑life Increase and 65 % Reduction in Maintenance Costs

For harsh operating conditions featuring heavy dust, moisture, impact loads and frequent start‑stop cycles, SAVI EPG‑series engineering‑plastic self‑lubricating bearings deliver a zero‑maintenance solution for the lifting and swinging mechanism of brush arms for a sanitation‑equipment manufacturer. It thoroughly addresses common industry pain points of conventional metal bearings: rapid wear, difficult lubrication and short service life.

Customer Background

This enterprise focuses on R&D and manufacturing of special‑purpose sanitation vehicles including road sweepers, washer‑sweepers and garbage compactor trucks. With an annual output of more than 2 000 sanitation vehicles, its products are widely adopted

 by sanitation authorities and municipal‑service institutions across provinces and cities nationwide. Its road sweepers adopt mainstream commercial‑vehicle chassis such as ISUZU and are equipped with combined disc‑and‑roller sweeping systems. Featuring high working efficiency and wide sweeping coverage, these vehicles enjoy solid market recognition.

Operating‑condition Challenges

As the core working assembly of road sweepers, the sweeping‑brush system operates persistently under extremely harsh conditions:

Abrasive wear from heavy dust: Large quantities of road dust, fine sand, PM2.5 and other particles are generated during sweeping operations. Dust penetrates through sealing gaps into bearings and causes three‑body abrasive wear which accelerates bearing failure.

Corrosion from moist sewage: Water‑spray dust suppression systems, rainy‑day operations and standing road water keep equipment in permanently humid environments. Corrosive media such as sewage, salt and leachate from waste erode the surface of metal bearings.

Impact and vibration loads: Bumpy road surfaces and curb sweeping subject brushes to continuous impact loads. Superimposed vibrations come from engines, blowers, road excitation and brush rotation, imposing stringent requirements on the bearings’ impact resistance.

Frequent start‑stop cycles and difficult maintenance: Sanitation work brings frequent vehicle start‑stop and repeated lifting‑swinging motions of brush arms. Work sites are far away from repair workshops, resulting in delayed and inadequate manual lubrication.

Pain Points of Conventional Solution

The customer originally used metal oil‑impregnated bearings for brush‑arm lifting‑swinging assemblies, suffering from rapid wear, short service life and frequent lubrication‑driven maintenance. After‑sales statistics show that hinge bearings of sweeping‑brush systems needed replacement every three months on average. Annual maintenance cost per single vehicle exceeded RMB 1800. Seizure‑induced brush‑arm failures caused 2‑3‑day downtime per repair, severely disrupting sanitation operation schedules. The customer was in urgent need of a bearing solution with zero‑maintenance, long‑life and harsh‑environment resistance.

Solution Development

Working‑condition Diagnosis & Requirement Analysis

SAVI technical team conducted on‑site surveys at the customer’s plant for comprehensive evaluation on brush‑arm lifting‑swinging mechanism. Measured parameters: swing angle ±25°, swing frequency 8‑12 cycles per minute, radial load at hinge points 500‑1200 N and operating temperature range ‑10℃ ~ 60℃.Coupled effects of dust, moisture and impact loads were fully assessed.

Motion type: small‑angle swinging plus intermittent rotation .

Load characteristics: medium‑to‑high load with impact load .

Environmental factors: heavy dust, high humidity and multi‑media corrosion .

Core requirements: zero‑maintenance, long service life and easy replacement.

Product Selection & Solution Design

Based on working‑condition analysis, SAVI technical team selected EPG medium‑to‑heavy‑load engineering‑plastic self‑lubricating bushings as the solution. The EPG‑series takes high‑performance engineering plastic as base material, reinforced by internal high‑strength fibre mesh structure to improve load‑bearing capacity. Compound special solid lubricants provide long‑term self‑lubrication, perfectly fitting application scenarios of medium‑to‑high load and swinging motion for brush arms.

Material selection: EPG fibre‑reinforced engineering plastic .

Maximum static surface pressure: 80 MPa .

Continuous operating temperature range: ‑40℃ ~ +130℃.