Checkpoint 1250 Series

Need help?

Do you have a question about the Checkpoint 1250 Series and is the answer not in the manual?

Summary

Pump Installation

Process Design and Setup

Inspect pump for transit damage. Contact customer service if damage is found. Includes a typical installation schematic.

Connecting The Chemical Supply

Instructions for cleaning suction lines and containers. Recommends filtration to prevent debris ingress.

Connecting The Supply Gas

Specifies clean compressed air or natural gas requirements and recommended pressure ranges.

Gas Recovery Systems Installation

Pump Operation

Bleeding and Priming the Pump

Step-by-step guide to remove air from the chemical head and prime the pump before operation.

Setting The Pump Stroke Rate

Guide to setting the pump's delivery rate using a calibration gauge.

Calculation of Stroke Rate

Explains how to calculate the pump's required stroke rate based on flow rate and pressure.

Pump Maintenance

Packing Adjustment

Detailed steps for adjusting the packing nut to stop leakage, emphasizing proper technique and avoiding overtightening.

Packing Replacement

Instructions for changing the pump packing, covering adapter sleeves, O-rings, and backup rings.

Lubrication

Guidance on lubricating the motor end for optimal pump life, with recommended types and methods.

Troubleshooting

Pump runs, but chemical does not discharge at the correct rate

Addresses issues like clogged suction check valves, lost prime, or relocated check valves.

Pump does not stroke

Troubleshooting steps for when the pump fails to initiate stroking, including low pressure or clogged valves.

Pump strokes erratically

Identifies causes for erratic stroking, such as fluctuating supply pressure or air leaks.

Chemical leakage from packing nut

Diagnoses causes of leakage from the packing nut, including loose or worn packing, or overtightening.

The CheckPoint Series 1250 Pneumatic Chemical Injection Pump is a versatile and robust device designed for long life, reliable performance, and low maintenance in chemical injection systems. It is engineered to exacting specifications for various field and plant applications.

Function Description:

The Series 1250 pump is primarily used for injecting chemicals into a process flow. It operates pneumatically, utilizing compressed air or natural gas as a driver fluid to move chemicals from a supply source into a system. The pump is capable of pulling air out of the chemical line and priming from up to twelve feet above the liquid level in the tank, even without flooded suction or positive chemical pressure, provided proper packing adjustment and bubble-tight suction lines are maintained. The pump's design allows for the recovery of exhaust gas in Gas Recovery (GR) models, which can be routed to a lower pressure gas system.

Important Technical Specifications:

Maximum Working Pressure: The chemical head is rated for a maximum working pressure of 7,500 psig. However, with air/gas supply pressures above 100 psig and smaller plunger sizes (¼" or less), pressures up to 18,000 psig or greater may be developed if discharge plumbing is blocked. A relief valve is mandatory if [supply air pressure] x [amplification ratio] ≥ [discharge plumbing design pressure] ≥ 7,500 psig.
Plunger Diameters and Amplification Ratios:
- 1/8 inch: 399
- 3/16 inch: 176
- 1/4 inch: 99
- 3/8 inch: 43
- 1/2 inch: 24
Gas Supply Requirements:
- Clean compressed air or natural gas.
- Minimum pressure: 20 psig.
- Maximum pressure: 200 psig.
- Required Gas Inlet Pressure: [DISCHARGE PRESSURE] / [AMPLIFICATION RATIO] X 1.3. If the result is less than 20 PSIG, use 20 PSIG.
Chemical Line Diameter: All process lines to and from the pump should be at least 3/8 inch diameter to ensure sufficient flow rates and minimize pressure drop.
Filtration: CheckPoint recommends filtration to ensure a maximum particulate size of 140 microns to prevent cavitation and increase pump life.
Maximum Recommended Stroke Rate:
- Continuous Use: 105 strokes per minute.
- Intermittent Use: 140 strokes per minute.
Gas Consumption Factors (SCFM @68F / Nm3/Hr @0C) for Series 1250:
- 1/8 inch: 0.1273 / 11.2538
- 3/16 inch: 0.0566 / 5.0017
- 1/4 inch: 0.0318 / 2.8134
- 3/8 inch: 0.0141 / 1.2504
- 1/2 inch: 0.0080 / 0.7034
- Gas supply pressure value must be absolute pressure (gauge pressure + atmospheric pressure).

Usage Features:

Mounting: Vertical mounting is recommended for gravity assistance with the suction check valve. Other orientations are possible, provided the chemical head is no higher than the motor's centerline. Spring-loaded suction checks are required for non-vertical mounting. Caution: Never orient the pump upside down, as this can lead to chemical leakage onto the motor and environmental atomization.
Installation Components: The manual recommends using a comprehensive set of components for optimal performance, including suction line block valve, air/gas supply block valve, gas recovery block valve, calibration gauge block valve, CP Calibration gauge, tank gauge, discharge line block valve, PRV (discharge line), CP 1250 Chemical pump, Regulator/Lubricator/Filter, CP Chemical Filter, and Pulsation Dampener.
Priming/Bleeding: The pump needs to be bled of air from the chemical head before operation. This involves opening the speed control valve to achieve a minimum of 60 strokes/minute, then opening the bleed screw until a solid stream of chemical is discharged.
Stroke Rate Setting: Pump speed can be adjusted using a speed control valve. Calibration gauges are recommended to accurately measure chemical delivery rates. The manual provides detailed instructions for calculating the target stroke rate based on desired flow rate, volume factor, and a Volume De-Rating Percentage (VDP) graph that accounts for discharge pressure.
Gas Recovery (GR Models): For GR models, exhaust gas can be recovered to a lower pressure system. The recovery pressure must be lower than the supply pressure, calculated using a specific formula provided in the manual.
Safety Precautions: Always ensure all process block valves are closed before disconnecting/re-installing the pump. A gas pressure regulator is crucial if supply pressures exceed 200 psig to prevent damage to motor seals and excessive discharge pressures. Operating the pump without chemical supply can decrease packing life and void warranty. Proper venting of the chemical tank or vessel is essential when using a pressure relief valve.

Maintenance Features:

Packing Adjustment: Packing adjustment is necessary when leakage is observed around the packing nut or weep hole. A CheckPoint T55-101 packing adjuster is recommended. Adjustment involves tightening the nut finger-tight, then an additional 1/6 turn at a time until leakage stops. Over-tightening can reduce packing life.
Packing Replacement: Detailed steps are provided for replacing packing, including removing the chemical head, packing nut, and suction check valve, then pushing out the old packing and sleeve. Specific instructions are given for 1/8" and 3/16" plunger sizes, which may require an adapter sleeve, O-ring, backup ring, and snap ring. Proper orientation of new packing rings and light greasing are crucial.
Lubrication: Although the Series 1250 motor is designed for "stone-dry" internal conditions, regular lubrication maximizes pump life.
- Periodic Lubrication: Introduce approximately 1cc of light hydraulic oil (ISO 3448 viscosity no. 20-32, possibly with antifreeze for cold conditions) into the air/gas inlet after disconnecting the supply line.
- Continuous Lubrication: Lubricator bottles can be installed in the gas supply line, set to one to two drops per minute (more in cold conditions).
Troubleshooting: The manual includes a comprehensive troubleshooting guide for common issues such as:
- Pump running but not discharging at the correct rate (clogged suction check valve, lost prime/air lock, re-located check valves, obstructed chemical entry, incorrect calibration gauge reading).
- Pump not stroking (speed control valve off, low air/gas supply pressure, high gas recovery pressure, clogged/gummed-up switching valve, swollen spool, incorrectly reinstalled alignment screw, worn motor seals).
- Pump stroking erratically (fluctuating supply pressure).
- Chemical leakage from packing nut (loose packing nut, worn packing, overtightened packing nut, chemical attacking packing elastomer/plunger material, abrasives in chemical).
Repair Services: CheckPoint offers an exchange program for rebuilt pumps and factory-direct repair services to ensure quality and reliability. Training sessions are also available.