What are the two standard operating speeds for the paddle?

Low speed is 140 ± 5 rpm and high speed is 285 ± 10 rpm (Table 1).

What is the specified nominal capacity of the mixing bowl?

The nominal capacity is 4.75 litres (Clause 4.2).

What is the required clearance between the paddle and the bowl?

The clearance should be approximately 3 mm. It's checked to ensure the paddle does not touch the bowl but is close enough for effective mixing (Clause 6).

IS 10890

: 1984

Specification for planetary mixer used in tests of cement and pozzolana

CurrentSpecializedSpecificationMaterials Science · Cement, Concrete, Aggregates and RCC

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This standard specifies the requirements for the design, construction, and performance of planetary mixers used for preparing cement mortar and paste for testing. It covers material specifications, component dimensions like the bowl and paddle, operating speeds, and clearances to ensure uniformity and repeatability in physical tests of cement and pozzolana.

Specification for planetary mixer used in tests of cement and pozzolana

Quick Reference Values

Low speed (paddle)140 ± 5 rpm

Low speed (mixing head)62 ± 5 rpm

High speed (paddle)285 ± 10 rpm

High speed (mixing head)125 ± 10 rpm

Mixing bowl nominal capacity4.75 litres

Paddle to bowl clearanceApproximately 3 mm

Practical Notes

Regular verification of paddle-to-bowl clearance using a feeler gauge is critical for ensuring consistent mixing action and preventing damage.

The specified speeds are for the mixer under load; running the mixer empty may show slightly different speeds.

The scraper attachment is vital for proper mixing by ensuring material on the sides of the bowl is incorporated, and should be kept in good condition.