The UHP equipment utilized by CleanBlast, LLC is rebuilt/refurbished between rentals so as to minimize equipment failures/breakdowns. CleanBlast, LLC sends a competent, certified UHP technician on each UHP project we perform, to maintain the mechanical integrity of the blasting equipment and perform preventative maintenance as needed. On long term rentals, it is typical to send a mechanic out, at no charge, to refurbish equipment onsite, to keep the project moving forward flawlessly.While specializing in UHP work, we also perform conventional blasting and painting at our clients request.
CleanBlast, LLC also owns many spreads of conventional blasting equipment and rent, new or low hour, compressors to accompany our equipment.
Ultra-High Pressure (UHP) General Information
Ultra-High Pressure (UHP) Waterjetting or Waterblasting provides distinct advantages over other methods of surface preparation. Environmental concerns are reduced because no dust is created by the waterjetting process and is therefore easier to contain. There is less residual risk to the owner/operator because contaminants do not become airborne and blasters are not subject to lung injuries such as silicosis. Waterblasting excels around sensitive equipment and large intakes where grit could get into moving parts possibly shutting down a compressor or turbine. It is also the preferred method on projects where large amounts of abrasives must be collected and disposed. Waterblasted surfaces are cleaner than those using traditional solid abrasive methods and, in addition, residual chlorides are removed which results in higher adhesion of the coating and longer coating life.
Lead based paint projects are great waterjet applications because of the elimination of airborne dust and ease of containment. The volume of waste is reduced since lead will not mix with water allowing operators the option of filtering lead paint chips and other contaminants. The residual water can then be treated in most sewer treatment facilities after this filtration.
Surface preparation by UHP uses pure water at 40,000psi. No inhibitors or abrasives are added to remove previously applied coatings. The pump creates pressure, water passes through hoses then out a handheld jetlance. The jetlance is available with multiple nozzles and barrel lengths. Various types of coatings require different flow rates and pressures for removal. The pressure is regulated by the pump and the flow rate is determined by the size of the tips in the nozzles.
Utilities Required on Jobsite:
- The pump requires potable water. The cleaner the water the better. Inlet pressure needs to be at least 60psi @10gpm.
- Compressed air is required for operation of the jetlances. The jetlance requires 90psi @ 32cfm.
- The pump will consume about 10gph operating at 2100rpm.
Inlet water quality:
- Flow International, the UHP system manufacturer, recommends use of municipal tap water with a hardness level of 17ppm or less.
- A pH level between 6.5 and 9.5 is required.
- Iron content should be less than 0.1ppm.
- Silica levels should not exceed 15ppm.
- Water temperature should be between 35 and 80 degrees Fahrenheit.
Discharge Water:
There are two types of discharge water from the UHP pump. Water discharged at the pump is cooling water and is very clean. It has gone through the filtration system and is used for cooling purposes. While this water is clean, it exits at about 160 degrees Fahrenheit. Typically this water is discharged on the ground or collected, cooled, and reused.
Surface preparation discharge water typically requires treatment. After the water strikes the surface, the runoff water can have paint chips, grease, coating particulates, or other solid or dissolved solids. The water can be put through filtration to collect solids. Then the properly filtered water is typically allowed to be discharged on the ground or into sewer treatment facilities on site.
Lead paint is a good example of a coating that will not mix with water. By removing the paint particles, the water is then lead free. This drastically reduces solid waste disposal on lead projects versus disposal of grit mixed with lead paint particles.
UHP System Specifications:
Diesel Husky pumps manufactured by Flow International provide 6.5gpm @ 40,000psi. The pump has a triplex plunger design that uses ceramic plungers and is direct coupled to the CAT engine using a vibration dampening coupling. The high pressure end of the pump has three removable heads. The plungers are lubricated by filtered inlet water with no external oil lubrication.
The control system of the pump has monitors and shutdowns controlled by relay logic controls. The controller monitors all safety features of the pump including low inlet water pressure, low oil pressure, and oil temperature levels.
A pressure control system allows the operating pressure to be infinitely adjustable from zero to 40,000psi. The pressure is controlled by an external compensation valve (ECV) that allows up to three hand tools to be controlled simultaneously from the pump. The control system for pressure control is hydraulically operated. The ECV bypasses any unused water at the pump.
This pump has over pressure protection. The over pressure mechanism consists of a valve that can be reset if pump pressure exceeds 46,000psi.
All high pressure plumbing components are rated at 60,000psi. All tubing is safety shielded with interlocking stainless steel conduit.
Jetlances, the cleaning wands, are rated at 45,000psi. These are lances with nozzles that rotate at 3000rpm and are air-driven. Each lance requires 90psi @ 32cfm. Three barrel lengths are available for these aluminum constructed tools that weigh 11bs. All lances have dual triggers and the on/off valve is controlled by a single air-operated valve. The lances are a dry shutoff design, meaning no water is dumped at the gun. All excess filtered water dumps at the pump.
Nozzle selections can be made from 2, 4, 5, and 9 jet heads, fan jets, and a 5 jet x 90 degree head. The 2 and 4 jet nozzles are typically used for thick rubber linings and extremely tenacious coatings; the 5 jet is the most common and cleans a three inch swath; the 5 jet x 90 degree nozzle is used for structural members; and the fan jet and 9 jet nozzles are used for sweeping and light removal. The nozzle inserts are hex headed and are easily changed with a wrench.
A secondary burst shield with wire braids surround the supply hose to the jetlance. This hose is 15ft. long, has a 3/16" inside diameter, and is rated at 45,000psi.
All high pressure supply hoses are rated at 40,000psi with a 2.5 safety factor. Hoses are typically 50ft in length.
A-3000 JetLance:
The A-3000 JetLance is a handheld gun that the operator uses to remove coatings. The gun has a pneumatic drive that rotates the nozzles at 3000rpms. There are three basic components to the gun:
- Tumble box - This is a small aluminum frame that is located 15ft. from the gun. It contains the air preparation equipment to dry and regulate the pressure to the gun. The tumble box also has a pneumatically controlled on/off valve that turns the UHP water on and off to the gun.
- Cleaning Lance - This is the A-3000 (gun) that is composed of a handle system and a rotary nozzle drive. There are two triggers on the gun. These triggers are there for safety and are designed so that the operator has to keep two hands on the gun to operate the tool.
- UHP Hose Whip - This is a 15ft. UHP hose that connects the tumble box to the gun. This hose is covered with a burst shield to protect the operator.
The A-3000 has a nozzle holder that is coupled to the end of the rotating shaft on the tool. Each nozzle holder holds between 2 and 9 individual nozzles. Each nozzle is replaceable. The amount of water flowing out the gun is determined by the size of the individual nozzles.
Engine:
The UHP pump is powered by a 3306DITA Caterpillar diesel engine.