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The Unique Oversize Grain Separator

Mobile stand alone compact screen for pre-sorting and separating out fine particles from general building rubble, asphalt, concrete, excavated material, etc. The ideal addition to the Compact Recycler RM60 — discharge height can be adjusted by fitting 2 additional skids. Can alse be used with RM80GO!.

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Rubble Master OS80 — Defined Value Grain in a Single Pass

Rubble Master OS80 recycling concrete

The OS80 mobile oversized grain separator is the most cost-effective solution for producing standardized final grain in a single pass. Only one operator is needed: the feed material is processed at maximum throughput with minimum wear by Rubble Master RM70GO! or RM80GO! crushers. The patented OS80 is fitter to the crusher’s discharge belt using quick-release levers, maintaining unrestricted movement of the crusher around the site. Three comb cascades reliably separate the defined oversized grain size. The return belt provides a closed-circuit system. The crusher / screen combination can be transported by low-loader and is ready for operation within 20 minutes of arrival on site. Power is supplied from the crusher generator.

  • Defined final grain size achieved in single screening
  • 100% separation of oversized grains using 3 comb cascades
  • Straightforward and cost-effective solution for obtaining graded material
  • Reduced fine grain content since it never reaches the crusher
  • Maximum production capacity with low wear
  • Comb cascades can be adjusted to each application
  • High discharge level — 9 ft 5 in (2.85 m for fine particles)
  • Power supplied from the crusher generator
  • Production capacity of 168 tons/hr (150 tonnes/hr)
  • Screen range ¾ – 2 in (18–50 mm), resulting in grain size of 0/20 to 0/50
  • Quicker return on investment that with stand-alone screens
OS80 screen combs

Graded material in a single pass: 3 comb cascades ensure strict separation into ¾” minus, 1″ minus, 1½” minus or 2″ minus.

OS80 oversized conveyor

Oversized conveyor produces second material gradation or feeds material to Re-Feed Belt (RFB) for closed-circuit crushing efficiency.

OS80 oversized refeed belt

Oversized Re-Feed Belt (RFB) completes a closed-circuit, maximizing crushing efficiency.

os80 screen combs

Defined final grain in a single pass in a closed circuit — only one operator required

refeed conveyor

Most cost-effective solution for grading material on-site — indispensable for road and rail projects

refeed belt

Profit from mobility: crusher and OS80 (including return belt) delivered with just one transporter


Show in millimeters (mm). Specifications subject to change in line with technical developments.

OS80 dimensions

Technical Specifications

Specifications subject to change in line with technical developments.

Rubble Master OS80
Total Weight 1,543 lbs (700 kg)
3 Comb Cascades With a screen length of 39.4 in (1000 mm) and a width of 15.75 in (400 mm)
Screened grain size from ¾–2″ (20–50 mm)
The oversize material separator is suspended from the end of the discharge conveyor belt
Main Dimensions Length
8′ 7″ (2600 mm)
3′ 9″ (1120 mm)
5′ (1510 mm)
Discharge Belt for Screened Material Belt Width
Discharge Height
32 in (800 mm)
7 ft 7 in (2300 mm)
9 ft 5 in (2850 mm) – RM80
Discharge Belt for Screened Material Belt Width
Discharge Height
14 in (350 mm)
6 ft 7 in (2000 mm)
6 ft 3 in (1890 mm) – RM80
Comb Cascade Mesh Size Fingers
1-¼ in (32 mm) — Standard ø 3/8 in (10 mm)
1-5/8 in (42 mm) ø 3/8 in (10 mm)
2-3/8 in (60 mm) ø 3/8 in (10 mm)
Adjustable from 1-1/8, 1-9/16 to 2-3/8 in (28, 40 to 60 mm) ø 3/8 in (10 mm)
Adjustable from 5/8, 1-1/8, 1-9/16 to 2-½ in (16, 28, 40 to 64 mm) ø 3/8 in (10 mm)
1-¼ in (32 mm) ø 5/16 in (8 mm)
7/8 in (22 mm) ø 5/16 in (8 mm)