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Fabricated Products
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R.A.S.
Industries Ltd. offers a number of standard product lines that will satisfy the
requirements of many industries. Standard sizes of conveyor pulleys, sprockets and take-up
frames are held in stock for immediate delivery. Custom products are readily fabricated to
customer’s specifications using pre-manufactured components, such as pulley end
discs, hubs, sprocket plates, etc.
click
here to browse our On-Line Product Catalog
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Fabrication Process
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Our fabrication techniques are the result of
years of experience and they always ensure that the fabricated pulley shell conforms to
the specified tolerances.
Pulley Rims
- rolled from CSA G40.21-44W steel as a minimum standard
- standard specification for longitudinal seam welds on "Mine Duty" pulleys is 100% penetration
- both the inside and the outside of the weld are ground smooth to eliminate stress raisers and
produce a "seamless" transition
- can also be machined to minimize the runout
and variation in concentricity and size, thus reducing the alternating stress range and
improving the fatigue life of the pulley
End Plates
R.A.S. Industries Ltd. was among the first in North America to introduce the concept of a solid profiled end
disc in conjunction with a compression fitting.
- hub weld, the most significant cause of pulley failure, is eliminated
- shafts no longer have to be keyed as the pulleys utilize keyless compression fittings
- designed
through dynamic stress analysis and the final geometry is optimized to minimize stress
concentrations and alternating stress ranges
- maximizes the pulley’s life and
reliability, and eliminates the cost of downtime
Shafting
- typically machined from blanks of AISI C4140 or C4340 steel
- 250 RMS micro-inches standard surface finish
- 125 RMS micro-inches below the locking device
- 63 RMS micro-inches on all radii and journals
- ensures shaft strength and eliminates stress concentrations
- design angle of slope at the pulley hub is generally limited to:
- 0.10% (0.0010 radians) for drive and high-tension pulley shafts
- 0.15% (0.0015 radians) for low-tension idler pulleys and all lower tension systems
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Non-Destructive Testing
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RASP Engineered
Class pulleys are subjected to a series of non-destructive tests to
ensure that the final product exceeds the design calculations without
any exceptions. Materials and welds are tested against defects through
ultrasonic (UT) testing or radiography (R) prior to stress relief.
Magnetic particle (MP) or liquid penetrant (LP) inspection are
performed after stress relief on finished welds and critical surfaces
to guarantee process and material integrity. All testing procedures
performed are in compliance with the latest applicable CSA or AWS
standards. The client can specify additional requirements (e.g.,
testing standards or acceptance criteria). R.A.S. Industries Ltd.
subcontracts independent third party inspectors to perform all
certified non-destructive examination.
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Quality Assurance Program
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To ensure the
excellence that our customers have come to expect, we operate under a Quality
Management System which is audited and
registered by the Quality Management Institute, a division of
the Canadian Standards Association.
Our Quality Assurance Manager is:
Gary Sutton
phone: (604) 590-0404 (ext.219)
click here for more details about our
Quality Assurance Program
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