Chilled Water Buffer Tanks

CBT-1

Standard Features:

  • Vertical construction
  • Carbon steel construction
  • ASME code section VIII, Div. 1
  • Red oxide shop primer exterior
  • 125 psi -20 to 400 degrees F design rating
  • Lifting lugs
  • 4″ High Skirt with base clips (6″ high on 54″ dia. and up)
  • Internal water diversion baffle
  • Non corrosive service
  • Upper inlet and outlet construction
  • Quick Ship inventory 5 available sizes from 130 gallon up to 528 gallon.

Optional Features:

  • Manways/ Handholes
  • Custom inlet/ outlet sizes, (quantities or locations)
  • R-16 Polyurethane, closed sell spray foam insulation w/ acrylic topcoat
  • Custom tank sizes
  • Grooved, Flanged and NPT connections
  • Stainless steel construction
  • Horizontal configuration with saddle supports
  • Contact factory for additional features
  • Horizontal buffer tanks are built to order.
    Consult factory for sizes, dimensions and specifications.

Chilled water bu­ffer tanks are essential components in modern day chiller systems. NST buff­er tanks are designed to increase the system’s capacity so water temperatures stabilize within the chiller manufacturers recommendations. When the cooling systems piping capacity is under sized, compressors will short cycle and temperature control is harder to maintain within the building. Chiller manufacturers recommend between 3 to 10 gallons per ton of nominal cooling capacity, in the piping system. Depending on the level of accuracy of temperature control, higher volumes may be required.

Niles Steel Tank’s Buffer Tanks are designed for use with Commercial chiller water systems and hydronic heating systems which may have insufficient water volume to maintain optimum operating temperature control. Niles offers gallon capacities from 130 gallon through 1000 and larger, additional sizes are available by contacting our sales department. Buffer tanks are constructed under the ASME Code, Section VIII., Division I. Vertical and horizontal tank designs are available with a center baffle plate. The top of the tank has NPT port for the air vent. Closed loop systems do not require a manway, but they are available if desired. Standard product design offering as well as custom configurations with alternate system connections are available. Available connections are Female National Pipe Threads, ANSI Flanges, and Grooved Pipe End connections. R-16 closed cell spray foam insulation is also available.

Model Gal. A B C D E F Weight
CBT-24-072 130 2″ NPT 1″ 1″ 76″ 24″ 4″ 375
CBT-30-075 210 3″ Flg 1″ 1″ 79″ 30″ 4″ 425
CBT-36-072 300 4″ Flg 1″ 1″ 76″ 36″ 4″ 633
CBT-36-094 400 4″ Flg 1″ 1″ 98″ 36″ 4″ 715
CBT-42-084 460 4″ Flg 1″ 1″ 88″ 42″ 4″ 1250
CBT-42-090 500 4″ Flg 1″ 1″ 94″ 42″ 4″ 1300
CBT-42-100 550 4″ Flg 1″ 1″ 104″ 42″ 4″ 1425
CBT-48-077 528 6″ Flg 1″ 1″ 81″ 48″ 4″ 1150
CBT-48-084 588 6″ Flg 1″ 1″ 88″ 48″ 4″ 1425
CBT-48-090 600 6″ Flg 1″ 1″ 94″ 48″ 4″ 1765
CBT-48-099 700 6″ Flg 1″ 1″ 103″ 48″ 4″ 1885
CBT-48-141 1000 6″ Flg 1″ 1″ 145″ 48″ 4″ 1957
CBT-54-096 850 6″ Flg 1″ 1″ 102″ 54″ 6″ 1630
CBT-54-147 1350 6″ Flg 1″ 1″ 163″ 54″ 6″ 2800
CBT-54-165 1530 6″ Flg 1″ 1″ 161″ 54″ 6″ 3100
CBT-60-096 1040 8″ Flg 1″ 1″ 102″ 60″ 6″ 2280
CBT-60-135 1500 8″ Flg 1″ 1″ 142″ 60″ 6″ 3375
CBT-60-177 2000 8″ Flg 1″ 1″ 183″ 60″ 6″ 4225


Sizing & Selection for Niles Steel Tank CBT Buffer Tanks:

1. Required Chiller Volume: ________ Gallons

Manufacturer of chiller unit’s recommended ‘gallons per ton’ of cooling. Typical 3 – 6 gallons per ton. Critical accuracy: 6 – 10 gallons per ton.

2. Actual Gallon Volume in the entire chiller system: _______ Gallons (including piping)

(1) Chiller requirements gallons: _______ (-) minus (2) Actual gallons in system = _______ gallon size of buffer tank.

Niles Steel Tank manufactures a standard line of vertical and horizontal buffer tanks. Vertical tanks are equipped with an internal baffle and standard flanged connections on 210 gallon and above. Horizontal tanks are equipped with a sparging tube. Baffles can be added to horizontal tanks as well. Since Niles Steel Tank is a custom tank fabricator, we would be happy to add or change our current design to suit your specific requirements. Grooved pipe end fitting are available in place of flanged connections. Our 2-part, closed cell foam spray on insulation can be added to any size tank and is durable enough for outdoor applications.


Specification:

Furnish and install as shown on plan, a Niles Steel Tank A.S.M.E. Buffer tank of _____gallons, _____ diameter with an overall height of _______. The tank must be designed, constructed and stamped 125 psi @ -20F to 400F in accordance with section VIII, Division I of the A.S.M.E. Boiler and Pressure Vessel code and registered with the National Board of boiler and pressure vessel inspections. The buffer tank shall be painted with 1) coat of red oxide shop primer paint. A manufacturers data report for pressure vessels, Form U-1A as required by the provisions of the A.S.M.E. Boiler and Pressure Vessel code shall be furnished for each buffer tank upon request.

To properly size the buffer tank, calculate the systems total capacity including all piping and terminal equipment. Subtract that number from the chiller manufacturers recommended system capacity. If a 100 ton chiller requires 1000 gallons of system capacity for high accuracy control and the total piping system totals only 600 gallons, a 400 gallon buffer tank would be required. (As an example)