Map the surface route
List every mixer, pump, valve, filter, choke, line diameter and pressure drop from make-down to use.
Mark where concentrated or partially hydrated polymer experiences the highest energy.
Create a reference solution
Prepare a fully hydrated solution with recorded water and concentration.
Measure baseline viscosity, temperature and filtration before the shear challenge.
Challenge one component
Pass identical solution through one device or controlled restriction at several operating points.
Avoid combining multiple unknown shear sources in the first diagnosis.
Measure retained properties
Use consistent viscosity method, shear rate and temperature after each pass.
Check filterability and visible gels because mechanical handling can affect more than viscosity.
Separate shear from chemistry
Run an unpumped aged control and confirm water, oxygen and temperature remained comparable.
This prevents chemical degradation from being assigned to a pump.
Inspect pump and valve selection
Review whether the equipment is operating within its intended flow and pressure range.
Cavitation, throttling and recirculation can create avoidable degradation.
Verify the modified route
Repeat the paired test after an equipment or operating change.
Confirm that retained viscosity improves without creating filtration or mixing problems.
Add field monitoring
Set sampling points and trigger limits for solution viscosity, pressure and filter behavior.
Preserve the baseline so gradual wear is visible.
Field interpretation and decision record
Locate potential shear before changing chemistry. Draw the solution path from wetting and aging through transfer pumps, control valves, filters, meters and injection equipment. Mark sample points that allow a before-and-after comparison. Record flow, pressure drop, pump type and operating condition with the samples. This turns a vague report of viscosity loss into an equipment-linked diagnosis and helps distinguish mechanical degradation from incomplete hydration, dilution error or temperature change.
Use the same analytical procedure at every sample point. Control temperature, elapsed time and instrument geometry because viscosity can shift even when the polymer has not passed through more equipment. Include a retained laboratory sample as a time control. If the field sample contains different water or contamination, document that difference before attributing the change to shear. Repeat the comparison during a stable operating period and, when practical, at more than one flow condition.
Laboratory shear screening should be calibrated to a known purpose. A high-speed mixer, capillary, valve loop or pump loop can rank candidates, but the result depends on concentration, exposure time and energy. Report the device and procedure rather than only a percentage loss. Compare viscosity, filterability and any application-specific measurement after exposure. A candidate with slightly lower initial viscosity may deliver a stronger value after the actual transfer path, so both initial and retained performance belong in the decision.
Corrective action may involve equipment as well as product selection. Check stock concentration, pump sizing, recirculation, throttling and unnecessary restrictions. Verify that filters are appropriate and not masking preparation problems. After a change, repeat the paired sampling and keep the incumbent reference. The release note should state the operating conditions under which retained performance was achieved and define triggers for retesting, such as a pump change, higher throughput, new water source or different polymer identity.