What does MMC mean in tolerance?
Maximum Material Condition
Maximum Material Condition (MMC) and Least Material Condition (LMC): Simple Definitions. MMC is the condition of a feature which contains the maximum amount of material, that is, the smallest hole or largest pin, within the stated limits of size.
What is meant by H7 tolerance?
International Tolerance grades For example: H7 (hole, tapped hole, or nut) and h7 (shaft or bolt). H7/h6 is a very common standard tolerance which gives a tight fit. For a shaft of the same size, h6 would mean 10+0−0.009, which means the shaft may be as small as 0.009 mm smaller than the base dimension and 0 mm larger.
What is MMC condition for holes and shafts?
Maximum Material Condition (MMC) exists when a part or feature contains the maximum amount of material everywhere, e.g. minimum size hole, or maximum size shaft.
What is MMC true position?
material conditions
True Position using material conditions (MMC/LMC) True position with a feature of size can control the location, orientation and the size of the feature all at once. MMC true position is helpful for creating functional gauges that can be used to quickly insert into the part see if everything is within spec.
What is MMC condition?
Definition: Maximum Material Condition or for short, MMC, is a feature of size symbol that describes the condition of a feature or part where the maximum amount of material (volume/size) exists within its dimensional tolerance.
What is the MMC of hole D?
Maximum Material Condition (MMC) It is the smallest hole diameter because a larger hole removes material, hence the smallest diameter provides for the greatest amount of material.
What does 10H7 mean?
Limit Plain Gauge
Limit Plain Gauge (10H7) The limit plain gauge is a gauge that has one measuring surface based on the maximum actual hole size and another measuring surface based on the minimum actual hole size.
What is H7 in hole dimension?
ISO Hole Tolerances (ISO 286-2) (3mm-400mm):
| Grade | NOMINAL HOLE SIZES (mm) | |
|---|---|---|
| G7 | +16 +4 | +28 +7 |
| G8 | +22 +4 | +40 +7 |
| H6 | +8 0 | +13 0 |
| H7 | +12 0 | +21 0 |
What is MMC virtual condition?
Virtual Condition is defined as the boundary generated by the collective effects of the specified MMC limit of size of a feature and any applicable geometric tolerance. For example, the MMC size of a shaft plus its axial Straightness tolerance, or the MMC size of a hole minus its Position tolerance.
How many datums are needed for true position?
Tolerance Of Position must always have one or more datum references except for two exceptions: Coaxial cylinders and a pattern of features of size used as a primary datum.
What is the MMC virtual condition size of one of the holes?
Figure VC1.1 For an internal feature of size, such as a hole, the virtual condition is equal to the size at MMC minus the size of the tolerance zone. For the hole in Figure VC1. 2, the diameter of the virtual condition is the diameter of the MMC hole minus the diameter of the position tolerance zone.