Rectangular Non-Pressure Stainless Steel Tanks
When a cylinder will not fit through the door or into the mechanical room, a rectangular tank uses the space you have. Swhift builds these self-supporting in 304L, in stock sizes or to your dimensions.
What Rectangular Non-Pressure Tanks are for
Non-pressure tanks are vented storage vessels — they hold liquid at atmospheric pressure, so the engineering effort goes into stiffness and cleanability rather than shell thickness. Ours are self-supporting, which means no external frame is required to hold the walls square when the tank is full.
Rectangular geometry is the reason most buyers choose these. A cylinder wastes the corners of a room and often cannot be walked through a standard doorway; a rectangular tank can be dimensioned around a stairwell, a crawl space or an existing equipment pad.
Our published size list runs from a 23 × 23 × 24 in. tank at 55 gallons up to a 72 × 72 × 144 in. tank at 3,231 gallons, with weights listed for each. Anything between or beyond those is built to your dimensions.
Typical applications
- Domestic and process water storage
- Solar thermal storage
- Chilled water and buffer tanks
- Food-grade holding and transfer
- Wastewater collection and equalization
Get a price on this tank
Stock size or custom — send what you have and we will quote it. Consultations are free.
Construction
How we build it
Every specification below is what Swhift actually publishes for this product line.
- Self-supporting — no external frame required
- 304L stainless steel standard; 316L available as an option
- FDA-approved materials — 100% tasteless and odorless
- Easy to clean, with optional removable lids for access
- Made in the U.S.A.
Options
What you can change
Stock or custom sizing is available across the range. These are the options most often specified.
- Stock sizes or built to your width, height and length
- Removable lids for cleaning and inspection access
- Optional lid bracing
- Insulated jackets available
- Heat exchange coils built to your requirement
- Mill, Soft Swirl or High Luster finish
- Half or full couplings, located to your drawing
| Width × Height | L 24 in. | L 58 in. | L 94 in. | L 142 in. |
|---|---|---|---|---|
| 23 × 23 in. | 55 gal | 125 gal | 226 gal | 337 gal |
| 23 × 59-1/4 in. | 140 gal | 348 gal | 564 gal | 852 gal |
| 34–36 × 59-1/4 in. | 209 gal | 505 gal | 818 gal | 1,237 gal |
| 46 × 59-1/4 in. | 285 gal | 689 gal | 1,116 gal | 1,686 gal |
Rectangular Non-Pressure Tanks we have built
Photographs from our shop and from installations. Every image on this site is our own work — there is no stock photography anywhere on it.
Specifications & order forms
Industries that use this tank
- Water & WastewaterContact vessels, softener tanks and storage for drinking water, process water and wastewater treatment.
- Food & RestaurantFood-grade tanks, custom components and one-off stainless work for production kitchens and food manufacturers.
- HealthcareTreated water storage, ozone contact vessels and custom stainless components for healthcare facilities.
Rectangular Non-Pressure Tanks: common questions
What does self-supporting mean?
The tank holds its own shape when full without an external frame or strapping. The walls, corners and any lid bracing are engineered to carry the hydrostatic load, so you set the tank in place and connect it rather than building a support structure around it.
Can a large tank be brought into an existing building?
That is usually the reason to choose rectangular over cylindrical. Give us the smallest opening on the route — door width, stair turn, hatch — and we will dimension the tank to pass through it while still hitting the capacity you need.
Do you insulate these tanks?
Insulated jackets are available. Tell us the service temperature and where the tank will sit, and we will include jacketing in the quote.
Can you build heat exchange coils into the tank?
Yes. We fabricate heat exchange coils and mount them inside the tank on welded supports. Send the duty or the coil specification with your quote request and we will price it with the tank.
How long is the warranty on a non-pressure tank?
Ten years, subject to the conditions in our written warranty — longer than the five years we put on pressure tanks, because a vented tank is not carrying a pressure load.
Related products
Solar Hot Water Tanks
Solar thermal storage in stainless rather than glass-lined steel — the product the solartanks.com name was built on.
ViewWater Chiller Tanks
Chilled water vessels built for continuous cold service, with coils and insulation where the duty needs them.
ViewStainless Steel Pressure Tanks
Vertical and horizontal pressure vessels in stock diameters from 9-5/8 in. to 60 in., or built to your drawing.
View
Start a project
Ready to quote your rectangular non-pressure tanks?
Send dimensions, a completed layout sheet, or a description of the job. If a stock size fits, we will point you at it rather than quoting a custom build.
Consultations are free. Every project is managed by a single production manager, so you talk to the person who knows your job.