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GRIFFCO Calibration Columns
- Product Details
- Specifications
- Sizes
- How to Use
GRIFFCO Calibration Columns
Check What the Dosing Pump Really Delivers
A calibration column is a clear, graduated tube fitted in the pump’s suction line, beside the chemical tank. Close the tank valve, let the pump draw from the column for a set time, and read how much it used. That is the pump’s true output at the site’s real conditions, so it can be set accurately and checked again at any time.
PVC or Glass
- PVC columns – tough clear PVC with no metal parts, 100 mL to 40 L. Three tops: Sealed with a vent connection (flooded suction, permanent installation), EZ-Clean with a removable top for chemicals that coat the tube (polymer, alum, ferric chloride, chlorine), and Dust Cap for suction lift, filled from the top.
- Glass columns – borosilicate glass tube with a protective shield, 30 mL to 20 L, end caps in PVC, CPVC, PP, PVDF, PTFE, 316 SS, Alloy 20 or Hastelloy C for aggressive chemicals and very small flows.
Graduations are in mL, with a US gallons-per-hour scale beside them. Ends are threaded (BSP or NPT), socket, flanged or union, including metric versions.
Specifications
| Item | PVC Columns | Glass Columns |
|---|---|---|
| Capacities | 100 mL – 40 L (15 sizes) | 30 mL – 20 L (12 sizes) |
| Tube | Clear Schedule 40 PVC | Borosilicate glass; outer shield up to 7 L |
| Top | Sealed with vent, EZ-Clean (removable) or dust cap | Sealed, with overflow connection |
| End Caps | PVC | PVC, CPVC, PP, PVDF, PTFE, 316 SS, Alloy 20, Hastelloy C |
| Connections | ½" – 4" (DN 15 – DN 100) | ¼" – 2" (to DN 50) |
| End Types | Threaded (NPT; BSP optional), socket, flanged or union; metric socket, flange and union available | |
| O-Rings | Viton® standard, EPDM optional (EZ-Clean and union ends) | Viton® standard, EPDM optional |
| Maximum Pressure | 1 bar | 0.45 bar |
| Scales | mL, plus US gallons per hour | |
| Flow Range (30-second test) | Up to 12 – 4,800 L/h, by size | Up to 3.6 – 2,400 L/h, by size |
| Approvals | NSF/ANSI 61 | – |
PVC Column Sizes
| Capacity | Max Flow (30 s) | Graduation | Height | Connection |
|---|---|---|---|---|
| 100 mL | 12 L/h | 1 mL | 279 mm | ½" (DN 15) |
| 200 mL | 24 L/h | 1 mL | 483 mm | ½" (DN 15) |
| 300 mL | 36 L/h | 5 mL | 330 mm | ½" (DN 15) |
| 500 mL | 60 L/h | 5 mL | 330 mm | ¾" (DN 20) |
| 1,000 mL | 120 L/h | 5 mL | 559 mm | ¾" (DN 20) |
| 2,000 mL | 240 L/h | 10 mL | 508 mm | 1" (DN 25) |
| 3,000 mL | 360 L/h | 10 mL | 432 mm | 1½" (DN 40) |
| 4,000 mL | 480 L/h | 10 mL | 940 mm | 1" (DN 25) |
| 5,000 mL | 600 L/h | 10 mL | 711 mm | 1½" (DN 40) |
| 7,000 mL | 840 L/h | 10 mL | 965 mm | 1½" (DN 40) |
| 10 L | 1,200 L/h | 100 mL | 635 mm | 2" (DN 50) |
| 15 L | 1,800 L/h | 100 mL | 914 mm | 2" (DN 50) |
| 20 L | 2,400 L/h | 100 mL | 1,194 mm | 2" (DN 50) |
| 30 L | 3,600 L/h | 200 mL | about 1,650 mm | 4" (DN 100) |
| 40 L | 4,800 L/h | 200 mL | about 1,970 mm | 4" (DN 100) |
Glass Column Sizes
| Capacity | Max Flow (30 s) | Graduation | Height | Connection |
|---|---|---|---|---|
| 30 mL | 3.6 L/h | 1 mL | 356 mm | ¼" |
| 100 mL | 12 L/h | 2 mL | 381 mm | ½" (DN 15) |
| 200 mL | 24 L/h | 2 mL | 533 mm | ½" (DN 15) |
| 500 mL | 60 L/h | 5 mL | 381 mm | ¾" (DN 20) |
| 1,000 mL | 120 L/h | 5 mL | 686 mm | ¾" (DN 20) |
| 2,000 mL | 240 L/h | 10 mL | 686 mm | 1" (DN 25) |
| 4,000 mL | 480 L/h | 10 mL | 991 mm | 1" (DN 25) |
| 5,000 mL | 600 L/h | 10 mL | 737 mm | 1½" (DN 40) |
| 7,000 mL | 840 L/h | 10 mL | 991 mm | 1½" (DN 40) |
| 10 L | 1,200 L/h | 100 mL | 686 mm | 2" (DN 50) |
| 15 L | 1,800 L/h | 100 mL | 991 mm | 2" (DN 50) |
| 20 L | 2,400 L/h | 100 mL | 1,295 mm | 2" (DN 50) |
Maximum flow is for a 30-second test; for a 60-second test the column suits twice the flow.
Installation
- Fit the column in the suction line between the tank and the pump, upright and level.
- Fit a valve on the line from the tank and one below the column, so the column can be isolated for normal running.
- Run the top vent back to the top of the chemical tank, or to drain.
- Glass columns: if the top is hard-piped, add about 300 mm of flexible hose at the top connection.
Checking the Pump
- Fill the column to the top mark (0 mL).
- Close the tank valve so the pump draws only from the column.
- Run the pump for a measured time, for example 30 seconds, and read how many mL it drew.
- Pump output in L/h = 3.6 × mL drawn ÷ seconds. Example: 150 mL in 30 seconds = 18 L/h.
- Adjust the pump and repeat until the output is right, then open the tank valve and close the column valve.
Applications
- Commissioning and routine checks of dosing pumps in water and wastewater treatment
- Chlorine, coagulant, polymer, acid and caustic feed
- Cooling tower, boiler and process chemical dosing
- Anywhere the dose must be proven, or pump output drifts with pressure, viscosity or wear
