The L-705 Laser is mounted into the gearbox through-hole (counter bore) by using our A-705 self-centering chuck, which has a specially adapted plate with a .750" (19 mm) hole that is centered to the feet to within .0005" (0.01 mm). The laser projects the axis of rotation of the extruder gearbox using a method we call the NORMIN (NORMal and INverted) proce¬dure.
The A-510 and A-510STA (or LTA) are designed so that the PSD (Position Sensing Detector) is centered axially between the four feet of the adapter, two of which are offset axially from the other two. This, in effect, puts the PSD on the pivot point of the adapter and allows the angle of incidence to the laser beam to vary by up to 45º. To insert the target into the barrel, a spring-loaded pole is attached to the target and the target cord is pulled. This tips the target forward, allowing it to easily slide into the bore. When the cord is released, the target and adapter "jam" into the bore, finding the center automatically. The weight of the pole keeps the target seated in the bore.
The A-510 2-Axis Bore Target and A-510STA Bore Adapter are specially designed to find the center of the bore, without any moving parts, to a tolerance of .0005" or 0.01 mm (with care, tolerances of .0002" or .005 mm can be achieved). The bore adapters are customized for each barrel diameter, but can handle a small range of diameter variance.
The L-705 Extruder Alignment Procedure
To perform an alignment, Hamar Laser's NORMIN procedure is used to put the laser beam on the axis of rotation of the gearbox, which is then projected down the barrel to the target. It works like this:
Insert the laser and the self-centering laser fixture into the gearbox counter bore and the A-510 Target and A-510LST Bore Adapter into the free end of the barrel. Write down the H (horizontal) and V (vertical) readings.
L-705 Extruder Alignment System – Laser in Normal Position
Rotate the gearbox by hand until the laser is inverted, using the built-in levels to determine the inverted position. Write down the second set of readings.
L-705 Extruder Alignment System – Laser in Inverted Position
- Average the horizontal values for NORMal and INverted, and then average the vertical values. The results determine the setpoints for the horizontal and vertical axes (see example below).
Turn the angular adjustment micrometers until the setpoints display on the readout.
L-705 Extruder Alignment System – Adjust Laser Until Readout Displays the Set Points
L-705 Extruder Alignment System – Laser Beam Concentric to Axis of Rotation
The reading produced after completing the NORMIN procedure is then a measure of the misalignment of the free end of the barrel to the gearbox axis of rotation. To align the barrel, it is best to move the target into the barrel just above the first support. Now the barrel can then be shimmed or moved until the readout displays .000" in both axes. If there are no other supports, then the barrel is aligned!
L-705 Extruder Alignment System—Target Inserted to First Adjustment Point
If there is more than one adjustment point for the barrel, then the target can be inserted into the barrel at the point just above the second support and the barrel can be shimmed or moved until the readout reads .000". Note: It is always advisable to move the target back to the first support point and check to see if adjusting the barrel at the second point caused the alignment at the first support to be slightly out of tolerance.
L-705 Extruder Alignment System – Target Inserted to Second Adjustment Point
L-705 Extruder Alignment System – Barrel Aligned to Gearbox
Using Bore9 Software
Hamar Laser’s new Bore9 software supports all of Hamar's past and present bore alignment equipment to create a powerful tool for measuring and aligning up to 50 bores. This comprehensive and easy-to-use program measures bore straightness (axis centering) and diameter change when using our targets in measuring mode. Applications include engine blocks, extruder barrels, hydraulic cylinders, large-bore gun barrels, printing press bearings, rotary compressors and turbines.
Bore9 features an easy 5-step process (described briefly below) that guides the user through the alignment process from setup to results. These results can be plotted, saved, and exported to an Excel spreadsheet.
- Step 1 – Bore Setup. The user enters setup information for the alignment check such as number of bores, distance between bore, bore diameters and bore straightness tolerances.
- Step 2 - Target Mounting Error. An optional step in the extruder alignment process for high accuracy applications to remove target adapter mounting errors, using the NORMIN method. The word NORMIN is a contraction of NORMal-INverted, which briefly describes the method.
- Step 3 – Laser Setup. On-screen instructions guide the user through setting up the laser and making it parallel to reference points.
- Step 4 – Record Data. Bore straightness data is recorded. There are several different sets of data that can be taken in this step.
- Step 5 –Results. Results of the recorded data are plotted on a graph and a least-squares, best-fit data algorithm is applied to generate the straightness results and to determine if they are in or out of tolerance. Plot data can be changed to reflect the position of the centerline of the bores relative to the end bores, selected bore numbers, the laser beam or a “Best Fit” line. The data for each point is recalculated automatically based upon which references are chosen. Reports are also generated in this step and can be customized to the four different bore references. Comments may be added and the report can be printed with a summary, a graph of the vertical and horizontal straightness, comments and a table showing the recorded data.
The L-700 Alignment System for Twin-Barrel Extruders
Using components from several different systems, Hamar Laser has developed a package to align twin-barrel extruders as quickly and accurately as possible. Our L-700 Spindle Laser and A-510 2-Axis Self-Centering Bore Target create a powerful package to align twin-barrel extruders up to 70% faster than conventional or optical borescope methods. With an accuracy of +/-.0002" (.005 mm) and our optional alignment software, the L-700 is the perfect extruder alignment tool.
The alignment of the twin-barrel extruders has never been easy. Traditional methods, such as using indicators to line up the outside of each barrel section, are subject to large stack-up errors and make the assumption that the outside of the barrel is parallel to the center line of the bore. Given the long length of the barrel, a slight error of .001" (.025 mm) to .002" (.05 mm) for each section can add up to .015" (.38 mm) or more misalignment at the free end of the barrel.
The L-700 laser virtually eliminates indicator stack-up errors by projecting the axis of rotation of the gearbox drive shaft out to 100 feet (30 M). This provides a single reference from which each section of the barrel can then be aligned. A target accuracy of .0002" (.005 mm) means very accurate alignment of each section of the extruder can be achieved.
Since the target can simultaneously show a live display of both horizontal and vertical readings, you can start aligning each section of the extruder without changing the setup or moving the laser. When the readout reads zero in the front and back (if desired) of the bore of an extruder section, it is aligned.
L-700 System Features
- Simple fixturing to mount the laser onto the drive shaft projecting its axis of rotation to 100 (30' M)
- Vertical and horizontal controls for both angle and center for adjustment of laser to shaft's precise axis of rotation
- Self-centering target comes with pole for insertion into long bores
- .0002" (.005 mm) target accuracy with live measurement data in two axes (vertical and horizontal center)
- Visible light beam
- Hand-held LED readouts show alignment data in 2 axes
- Laser runs for up to 8 hours on a standard, replaceable 9-volt battery
- Windows-based software with large, color graphics
- Compact and rugged (4" L x 2.9" H x 1.75" W or 101 mm x 73 mm x 44 mm)
How the Alignment System Works
The L-700 Laser is affixed to the gearbox output shaft using a self-centering chuck with a specially designed plate that has a .500" (12 mm) hole (matches stud on back of laser) that has been aligned to the feet. The laser is attached to the chuck and it is placed over the output shaft. A 2-axis target and the NORMIN procedure are used to position the laser beam on the axis of rotation of the gearbox shaft. When removed, the laser will project the gearbox shaft centerline out to 100 feet (30 M).
A customized adapter (A-510STA/LTA) and pole are attached to the A-510 Target and the assembly is inserted into the free end of the barrel. The target automati¬cally centers itself and immediately pro¬vides a horizontal and vertical measurement of alignment. If the twin-barrel is under construction, the system can be used to align each section of the barrel. This is a much better alignment method than using indicators on the outside of the barrel or relying on pins and manufacturing to perform the alignment, both of which are subject to significant stack up errors.
If the extruder to be aligned is already installed, the A-510 target can be inserted into the barrel and positioned over adjustment points. The digital readout displays the misalignment numbers dynamically. Simply adjust the barrel until the readout reads zero and that section is aligned. If there is radial adjustment in each individual barrel section, then the same procedure can be followed for the other bore.