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SSPC-Guide 6
<br />October 1, 2004
<br />5.1.3 Power Tool Cleaning with LocaUzed Exhaust:
<br />Includes power tools which contain integral vacuum-equipped
<br />shrouding. A brush or rubber sieeve on the shrouding conforms
<br />to the surface to enhance the control of dust and debris col-
<br />lection.
<br />5.1.4 Waterjetting Without Abrasive: Includes all types
<br />of pressurized water jetting systems. The action of the water
<br />with or without cleaning solutions or rust inhibitors provides
<br />the cleaning. Pressures are as stated by the manufacturer of
<br />the equipment. Note that when removing hazardous paints,
<br />high pressures and certain cleaning solutions may cause the
<br />hazardous substances to be carried with the water. This water
<br />should be recycled or collected and disposed of properly. Water
<br />jetting at pressures from 10,000 to 30,000 psi is often called
<br />high pressure water jetting, and, at pressures over 30,000 psi,
<br />ultra high pressure water jetting.
<br />5.1.5 Waterjetting With Abrasive: Includes pressurized
<br />water jetting systems with abrasive injection. Variations may
<br />mix abrasive and water in a separate tank or at the nozzle,
<br />or inject abrasive into the water stream. Pressures required
<br />as stated by the manufacturer of the equipment. Note that
<br />when removing hazardous paints, high pressures and certain
<br />cleaning solutions or rust inhibitors may cause the hazardous
<br />substances to be carried with the water. This water should be
<br />recycled or collected and disposed of properly. Water jetting
<br />at pressures from 10,000 to 30,000 psi is often called high
<br />pressure water jetting, and, at pressures over 30,000 psi, ultra
<br />high pressure water jetting.
<br />5.1.6 Wet Abrasive Blast Cleaning: Includescompressed
<br />air blasting systems that incorporate water into the blast stream.
<br />Variations may mix abrasive and water in a separate tank or
<br />at the nozzle, or apply the water to the abrasive as it exits the
<br />nozzle. Pressures are required as stated bythe manufacturerof
<br />the equipment. Note that when removing hazardous paints, high
<br />pressures and certain cleaning solutions or rust inhibitors may
<br />cause the hazardous substances to be carried with the water.
<br />This water should be collected and disposed of properly.
<br />5.1.7 Open Abrasive Blast Cleaning wlth Expendable
<br />Abrasives: Blast cleaning using compressed air to propel
<br />abrasives through noules. The spent abrasives, paint, debris,
<br />trash, etc. are collected for disposal. Expendable abrasives
<br />are those which are not normally reused after the initial blast.
<br />For the purposes of this guide, expendable abrasives include
<br />natural minerals (e.g., quartz sand, flint, garnet, staurolite,
<br />olivine, etc.), and mineral slags formed in electric power gen-
<br />eration (coal slag) or in smelting metals such as copper or
<br />nickel. Manufactured abrasives, such as aluminum oxide, and
<br />vegetable abrasives (e.g., walnut shell, corn cob, etc.) might
<br />also be included. CAUTION: Some expendable abrasives may
<br />contain heavy metals.
<br />5.1.8 Open Abrasive Blast Cleaning with Reusable
<br />Abrasives: Blast cleaning using compressed air to propel
<br />abrasives through noules, except that the abrasives are col-
<br />lected, cleaned of paint and debris, and reused. Cast steei,
<br />malleable iron, chilled cast iron, garnet, and aluminum oxide
<br />abrasives are typically used. An abrasive's ability to be re-used
<br />depends on its type, durability, and hardness. (For more infor-
<br />mation, see SSPC-AB 2.)The abrasive reclaimer (collection
<br />and cleaning equipment) may be an integral part of the blast
<br />machine or it may be housed in a separate machine. Blast-
<br />ing and abrasive reclamation may operate simultaneously or
<br />independently. The use of re-usable abrasives may reduce
<br />the volume of waste by a factor of 50 or more compared to
<br />expendable abrasives.
<br />5.1.9 Closed Abrasive Blast Cleaning with Re-Usable
<br />Abrasives: Blast cleaning using compressed air or centrifugal
<br />wheels within a vacuum assembly to propel abrasives toward
<br />a surface and simultaneously remove the abrasive and debris.
<br />Once the collected abrasives are cleaned of paint and debris,
<br />they are reused. Reusable abrasives may reduce the volume
<br />of waste by a factor of 50 or more compared to expendable
<br />abrasives. Systems can be recirculating or non-recirculating.
<br />5.1.9.1 Vacuum Blasting: Blast cleaning using com-
<br />pressed air to propel abrasives toward a surface. A special
<br />vacuum assembly equipped with a brush or rubber sleeve
<br />surrounds the blast nozzle, sealing it to the surtace. The seal
<br />must be maintained between the assembly and the surface
<br />to create a completely closed blasting cycle. The abrasive is
<br />recirculated automatically, cleaned of paint and debris, and
<br />returned for reuse. Cast steel, malleable iron, chilled cast iron,
<br />and aluminum oxide abrasives are typically used.
<br />5.1.9.2 Wheel Blast Cleaning: Blast cleaning wheel as-
<br />semblies that propel abrasive to the surface using centrifugal
<br />force. A special vacuum assembly with a mask that seals the
<br />centrifugal wheel assembly to the surface is required. The seal
<br />must be maintained between the assembly and the surface
<br />to create a completely closed blasting cycle. The abrasive is
<br />recirculated automatically, cleaned of paint and debris, and
<br />returned for reuse. Cast steel, malleable iron, or chilled cast
<br />iron abrasives are rypically used.
<br />5.1.9.3 Mechanlcal Non-Recirculating Blast System:
<br />Equipmentthat shrouds the blast nozzle to contain and remove
<br />the debris. The abrasive may or may not be reused. If it is
<br />reused, cleaning the debris from the abrasive is accomplished
<br />as a separate operation.
<br />5.1.10 Chemical Strlpping: Use of chemical stripping
<br />solutions or slurries applied to the paint surface. Effectiveness
<br />of the chemicals may be enhanced by applying a cover such
<br />as cloth or paper to the surtace after application to prevent
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