Magnetic Pulley (Sheave) Alignment Lasers
Magnetic Pulley (Sheave) Alignment Defined
All Johnson pulley (sheave) alignment systems are accurate enough to exceed belt manufactures' recommendations for drive belt alignment. This includes Standard V, Synchronous, Polyflex® and Micro-V® belts that should be aligned within ¼° or 1/16" per foot of drive center distance. This means that the best value to the maintenance professional is a sheave alignment system with a combination of features that best suits the aptitude of the user the machinery that will require aligning.
Johnson's Sheave Alignment product line has been designed to offer maximum value to our customer. Value is comprised of the following important product attributes:
Easy to Use
The basic requirement of the task is to align two sheaves in order to minimize belt and bearing wear and minimize the likelihood that a belt could be thrown off of the drive mechanism. In the past, a millwright was forced to use a string and straight edge which made the alignment process time consuming and costly. So a sheave alignment setup that has few required parts, meets and exceeds all accuracy requirements and is simple to use on the greatest variety of machinery is the better value.
Easy to Understand
"The fewer the parts the better" is a cliché that applies to the Johnson Sheave Alignment laser system. The tools are designed with user simplicity in mind; the easier the tools are to understand the more likely they'll be used by junior and senior maintenance personnel. The laser alignment tool and parts are intuitive and visibly show parallel or non-parallel geometry.
Simple--Few Parts
A parallel laser line on one sheave and a target(s) on the other sheave is all that's required. A minimum of three targets for edge alignment systems show the angle and offset error to the maintenance person. Groove alignment systems, reflective systems and digital systems do not offer the simplicity and versatility of the Johnson Sheave Alignment tool.
Easy to Read
Viewing the laser line on a target needs to be direct and easily interpreted. A crooked line means an adjustment is required. A jagged, 3D line from a digital sheave alignment system is not easily understood. A digital reading that's not viewable to the human eye makes adjustments counter intuitive. When adjustments are made, the moving laser line needs to be seen from the point of view of the maintenance person making the corrections. It's not easy to see between or under the belts when groove targets are used. The new ColorGageTM Target System used with the Johnson Sheave Alignment System uses color change and reflective technology to improve contrast. This makes it easier to read.
Maximum Versatility
The tool and/or approach that covers the greatest variety of sheave sizes, spacing, belt guards and types of sheaves is the best value. 100 years of pulley and sheave transmissions has produced many different belt styles, sheave designs and general applications. The sheave alignment system that can adapt to the greatest variety of power transmission systems using the least amount of accessories wins. This includes indoor and outdoor applications and working in high ambient light conditions. Example: Roof top cooling systems for commercial air conditioning systems are usually located in bright ambient light or direct sunlight. The new green laser alignment systems overcome bright light visibility problems.
Assured Durability
The industrial environment that sheave alignment systems are used in is dirty, greasy and oily and the handling of the parts and components is rough and abusive. This means that the magnetic laser transmitter, targets, receiver and groove tools take a beating every time they are slapped onto the sheave face or groove. In addition, the laser and targets will be dropped onto concrete multiple times during their lifetime. Therefore the design must be robust and resilient. Example: Normal usage can remove hard anodized surface hardening to Rockwell 65C. This occurs as the laser transmitter is repeatedly slapped onto the sheave face. Even the magnets need to be plated to keep rust from forming. This means that the effectiveness of the system, including calibration and accuracy, are compromised by every use. Poor designs or complex approaches just make matters worse over time. Durability is a big part of perceived value.
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