Gear Box Ecoman 2a 1

8/3/2019 Gear Box Ecoman 2a 1

1/21


2/21

Gear Box Coupling Halves Alignment

Poor alignment can cause vibration that will be transmittedthrough the machine and cause wear and lead to premature

failure of mechanical seal, bearings, couplings and other

machine elements.


3/21

Alignment techniques

1. Straight edge to bring the machines into rough alignment.

2. Rim and face method. This method produces acceptable

results, but is less accurate than the reverse dial indicator

method.

3. Reverse dial alignment does not require removal of the

coupling to collect data.

4. Laser


4/21

Types of misalignment

Parallel misalignment

Angular misalignment


5/21

Pre-alignment conditions

1. Machine shaft axes are roughly aligned within 50 mils.

2. The foundation base plate is adequate

3. All machine feet are in full contact with the foundation base

plate or supports.

4. Piping is not inducing strain onto the machine cases. Pipingshould be aligned to within 2 mils of their flanges.

5. The machine feet bolt holes have enough clearance to conduct

alignment activity. How ?


6/21

A pipe sleeve about 2 1/2 diameters larger than the bolt should

be used . Why?

To allow movement for the final positioning of the bolts.


7/21

6. Radial run out is less than 2 mils.

7. Coupling face run out is less than

mil.


8/21

8. The required amount of cold offset compensation

(Thermal growth) is available from the machine

manufacturer.

L = L()(T)

L = thermal expansion

L = height centerline to base of machine

= coefficient of thermal expansion of material

T =change in temperature from ambient


9/21

Material a (in./in./F)Aluminum 0.0000126

Bronze 0.0000101Cast iron 0.0000059

Copper 0.0000092Mild steel 0.0000063Stainless 0.0000074


10/21

9-The alignment bracketry is appropriate to the activity

required.


11/21

10.The moveable machine has as initial shim pack installed; the

shim pack should be comprised of one thick spacer and one or

two smaller shims. Too many shims will act like a spring

causing additional problems.

11.shims are adjusted during the leveling process

12.Shim material should preferably be corrosion resistant and of

sufficient proportions to support the weight of the machine.If the shims are crushed under the load of the machine then

level and alignment will be destroyed.


12/21

13- Shims may be either flat material or wedge shaped

When flat shim material is used it is recommended that it is

shaped to fit around the anchor bolts.

Anchor Bolt


13/21

Wedge-shaped shims provide an easy method of adjustment

but care must be taken to ensure that they are installed

correctly so that they are aligned with the bedplate and fully

support the load

Right and wrong ways of using wedge shaped shims.


14/21

14- Check for Soft Foot


15/21

Soft Foot check procedure

i. Move indicators to 12 o'clock position, depress indicators and

then zero

ii. Loosen one base bolt. If indicator moves away form zero, place

the amount of shims that will slide under that foot. Retighten bolt

iii. Repeat this procedure for the remaining feet.


16/21

15. Bar sag Correction

i. Installing the bracket and dial indicator, in the identical

arrangement to be used on the machine, onto a pipe.

ii. Zero the indicator while it is on top of the pipe.

iii. Rotate the pipe 180 so that the indicator is at the bottom

position.

iv. The indicator will now display twice the amount of bar sag.


17/21

16- Pipe Strain

Pipe strain is the force exerted on the fixed component from

suction and discharge piping that is not supported properly.

If pipe strain is not corrected, it may be difficult to align the

shafts properlyy

Piping flanges must be brought squarely together before the

bolts are tightened.Flanges can be assembled with no more than 200-pounds force

(an average adult can arm push 200 pounds).


18/21

How to check for residual pipe strain ?

1- Four dial indicators, in orthogonal directions, and "zeroed."

One of the dial indicators is mounted at 12 oclock, and the other

is mounted at either 3 oclock or 9 oclock


19/21

2- All of the hold down bolts shall be completely loosened. This

will relieve any pipe strain that may have been present


20/21

3-Movements greater than 0.005 inch indicate external strain

on the machine. The strain shall be corrected prior to

proceeding.


21/21

Parallel misalignment:

This occurs when the shaft center-lines remain parallel, but are

offset

Types of misalignment?

Angular misalignment:

This occurs when the shaft center-lines are out of parallel

Gear Box Ecoman 2a 1

Documents

Transcript of Gear Box Ecoman 2a 1