** Metal Surface Pre-Treatment - Acid Feed/Phosphatizing Options

Three Ways to Introduce Chemical
into a Super Max™ Pressure Washer

Super Max™ AF series users have options as to the method of introducing chemicals as they pass through our pressure washers - inlet side injection (sometimes referred to as high side injection), downstream injection and external chemical pump injection.

1. Inlet side injection is the normal method used in hot, high-pressure washers and is suitable for alkaline (high PH) detergent. With inlet side injection the chemical passes through the high pressure pump, heating coil, unloader valve and other components containing brass or other materials that will tolerate alkaline solutions, but not acids or solvents.

2. Downstream injection is the most common method used for injection of acids (including phosphatizer) and aggressive solvents. With downstream injection the chemical contacts only the injector, high-pressure hose, trigger gun, wand and nozzle. These components are relatively easy to protect against corrosive attack.

3. External chemical injection is a also suitable for acids and is sometimes used for special circumstances.

The choice of method for chemical injection also determines whether the chemical is applied under high-pressure or low-pressure. Inlet side injection creates high-pressure chemical application where the water/chemical mixture is sprayed at the normal pressure rating (1500 PSI, etc.) onto a surface. The chemical flow is then shut off and high-pressure clear water is used to rinse. Downstream injection creates low-pressure (100-200PSI) chemical application followed by high-pressure rinse. A means to switch from low to high-pressure and vice versa is located at the wand. External chemical pump application creates high-pressure application.

Advantages and Disadvantages to Each Method

There are advantages and disadvantages to each method described in Section 1 and there are instances where either of the three would be the best choice. However, we have determined by experience of our customers and our own manufacturing process (we phosphatize, prime and powder coat all machines) that using the downstream application method (also known as high/low system) is the best choice for most applications. Our standard phosphatizing system is therefore based on downstream injection. The other methods, as well as an array of other design features, are available on special order from Daimer®.

The standard Daimer Acid Feed/Phosphatizing System consists of the following features:

· Stainless steel downstream injector with chemical proportioning adjustment. This device is mounted at the outlet of the heating coil.

· Stainless steel fittings and parts from the injector to the nozzles.

· Stainless steel dual lance wand with crossover valve. The wand has one trigger gun and two side-by-side tubes that form the lance. On the outlet of one tube is a high-pressure nozzle and the other a low-pressure nozzle. By opening and closing a crossover valve the water flow is directed through the high-pressure nozzle or the low-pressure nozzle, not both at the same time.

· Clear plastic siphon pickup tube with a foot screen exiting the front of the machine to draw chemical directly from a bucket or drum.

· On/Off panel valve for chemical pickup.

Optional Features that can be added to Standard
Daimer® Super Max™ Acid Feed Machines

· Multiple chemical feeds. The downstream injector can be equipped with a special manifold and multiple siphon pickup tubes to be used one at a time with a flush function between chemicals. Chemicals can be selected with manual valves on machine or by electrical solenoid valves from a remote station.

· Remote control station. Work area can be some distance away from pressure washer and connected by hard pipe or hose. The pressure washer is controlled from the work area by switches and controls on a wall mounted NEMA 4X (water proof and corrosion resistant) control box. 24 VAC control wiring is run from pressure washer to work area.

· Multiple pressure washer guns for either one at a time use or simultaneous use. This can influence the machine capacity and operating procedure. Requires careful engineering evaluation of pros and cons.

· Steam combination control. This is not recommended and not needed for phosphatizing, but is sometimes wanted for other applications. Phosphatizer is best applied at 160ºF - 190ºF.

· Automatic motor control or automatic lockout or both.

· Features to allow use of recycled water.

· Non-pressurized water feeds (from a tank).

· Other site specific needs to adapt to a specific unusual environment.

All requests for non-standard features require engineering review and pricing. Contact a Daimer Product Specialist for more information.

Non-Standard Phosphatizing Systems
That can be Designed and Built by Daimer

· External chemical pump injection system.

· Inlet side chemical injection with special pumps and components. This method is not as common and typically a much more expensive option.

We encourage you to contact a Daimer Product Specialist if you have any questions or require further information. Our goal is to provide our customers with the absolute best configuration to meet their specific requirements.

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