Polyurea Spray machines, also referred to as proportioners, are highly complex pieces of equipment. For many spray foam insulation and roofing businesses, these machines serve as the backbone of the job site. They are a critical piece of machinery, and usually essential to efficient operations.

With that said, it’s vital to perform weekly (and sometimes daily) maintenance on these valuable machines.

Here are our suggestions:

Generator

Check the Oil Level and the coolant level daily before starting the generator. Start the generator with no load applied to it. Allow the generator to warm up for five minutes before applying a load to it. Remove all loads and allow the generator to cool down for five minutes with no load before shutting off.

Air Compressor

Always start electric air compressors before turning on power to the proportioner. Drain the receiver tank daily, in the morning as the air has cooled overnight and the moisture has condensed and dropped down to the bottom of the receiver tank. Check the air compressor oil level every day before starting. For gasoline powered air compressors,

check the engine oil level and fuel level daily before starting. Drain all filters bowls daily in the morning. Check all desiccant dryers for spent desiccant beads and replace as needed.

Transfer System

Check your drum top desiccant dryer(s) for spent desiccant and replace as needed. If you have return valves, open them and allow both transfer pumps to cycle Material through the system and back to the drums. Get in the habit of doing this every morning and you will learn what your transfer pumps sound like when they are healthy and operating properly. When you have an issue, you will hear it in the morning (i.e. hanging up at the bottom of the stroke and not shifting or pumping faster or slower than normal etc.) and you can address the issue before it affects your product. Ensure your drum temperatures are where they should be as recommended by your material supplier.

Proportioners

Clean the proportioner inlet strainers weekly or every other week as needed. [Tech trick – Apply white lithium grease to the wye strainer cap threads before re-installing – this will aid in removal your next time around.] Check that the A side pump lubricant is circulating properly through the lube pump. Change the fluid when it turns milky white or brown or when it begins to thicken. Lubricant must circulate around the A side Pump Rod to prevent damage to the pump rod and upper packings. If the lubricant is brown or the color of your ISO, your pump rod and/or packings have been damaged or worn and material is leaking past them into your lubricant system and you should schedule time to repair the pump as soon as possible.

Spray Gun

Check that the gun safety operates properly daily before opening the fluid shut off valves. Check the gun end for misting when you open the fluid shut off valves. If the gun has a mist of material out of the front of the gun when you open a shut off valve there is an internal leak inside the gun that should be remedied before spraying. Check that

the gun screens are clean weekly or as needed. A dirty gun screen will cause high pressure on that side and usually off ratio material is the result. Grease the gun daily at shut down if recommended by the manufacturer for that gun model. Do not over grease, refer to the spray gun manual for greasing instructions.

Trucks and Trailers 

Keep your trucks and trailers clean. Wipe up all spills immediately. Blow dust off all equipment every week. Wipe down all equipment as needed. 

If you would like more information about monthly maintenance tips for your polyuria spray machine, contact Intech Equipment and Supply. We are proud to provide contractors a one-stop resource for all of the essential spray foam equipment and machinery needed to keep their projects running smoothly.