Frequently Asked Questions
Q. What determines what plastic is used for tank fabrication?
A. Polyethylene is used for holding liquids that are used for human consumption. This will ensure that it meets FDA standards. Since high density polyethylene is more difficult to fabricate, the price is higher, polypropylene is used for waste holding tanks.
Q. What are the drawbacks of molded tanks verses fabricated tanks?
A. Molded tanks are made from a mold. The cost of a molded tank usually will be less expensive than a custom built tank. The molded tank is usually made of low or medium density (softer) polyethylene. The insides are usually not as smooth, and the wall thickness isn't as consistant as a tank that is fabricated of high density polyethylene. You will also note that full baffles are not a part of the insides of the tank. Generally because of the "spongy" material, failure will occur at the couplings. And if you have a space requirement, an "off the shelf" tank shape might not even exist.
Q. Why are most molded tanks constructed of polyethylene, and our waste tanks made of polypropylene?
A. Polypropylene is more difficult to mold. We have built tanks for 25 years using polypropylene. It is chemically resistant to just about everything. Also it is a less expensive material, and easier to fabricate. We build our waste tanks with a minimum 3/8" wall. Basically we are giving you more for your money.
Q. What determines what wall thickness is used?
A. Wall thickness is important! Water weighs 8.33 lb. per gallon. Usually a tank fabricated correctly can safety contain the solution. The rule of thumb is 50 to 70 gallons can be held in a tank with a 3/8" wall, depending on the configuration. However baffles have to be placed in the tank at the correct locations. This is done to divide the tank into several smaller tanks, and to decrease any wave action.
Q. I want the wall to be thicker, but I was told it isn't necessary.
A. A correctly designed and built tank will hold the water, and take the motion that occurs within the tank. Having a heavy wall will only add weight. The wall should be able to flex somewhat with a wave. If it doesn't the shock will be at the corners. This can blow out the seams. The tank should be secured well within the area it is installed. Basically the thicker the wall, the easier it can be to break the weld, if slammed or jolted repeatedly. Molded tanks generally are about 3/16" to 1/4" thickness averaged in the wall and a full height baffle is impossible to mold within the tank.
Q. How are baffles determined, and are they necessary?
A. Baffles should be put in most water tanks. The motion will cause a wave to occur within the tank. A well built tank will be split up evenly into equal sized compartments (I try to divide the tank into 20 gallon compartments). The baffle will be full height, with all four corners opened. The openings should allow water to flow through, but at a reduced rate. It requires some basic math to figure the correct size of the openings.
My commitment to YOU!
For over 20 years I have been fabricating tanks. I take pride in my tanks. As a customer, you are important to me. I will build you one tank, or ten tanks. I will communicate with you, discuss your project, fabricate the tank, test it fully, and ship it to you.
Your project is as important to me, as it is to you!
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