Test bench staff hold hydraulic know-how: HR for industrial pump manufacturers

A customer's inspector is booked to witness tests on a batch of split-case pumps for a water scheme. The bench lead falls ill the day before. His junior can mount a pump, couple the motor and open the suction and delivery valves. What he cannot judge is whether a curve sitting slightly under the duty point is within the agreed band, or whether the impeller should be trimmed and the pump re-run. The witness test is put off by a week. The payment tied to dispatch moves with it.

Our industrial pump manufacturers page leads with this strain. Across the industrial machinery group, one-person knowledge usually hides in the drawing office. In a pump works it hides on the test bed, after the last spanner is put down.

• How to rig each pump family on the bed: baseplate, coupling alignment, suction pipe length and priming.
• Which flow meter, pressure transducer and throttle valve to use for each size, and how to spot a reading that is the rig's fault rather than the pump's.
• How to take readings across the curve from shut-off to run-out, and when a point needs repeating.
• How to read vibration, bearing temperature, noise and gland or seal leakage during the run.
• How much impeller to trim when a pump runs high, and how a trim shifts the curve.
• How to run a casing pressure test safely, and how to handle a customer's inspector during a witness test.

Much of this is judgement built from countless runs. A senior bench technician hears cavitation before the suction gauge flickers. He sees from a sagging curve that a wear ring clearance is wrong, or from a high power reading that the impeller is rubbing.

Pumps are built in batches, and every one passes the bench. If one person clears them, the bench sets the pace for the whole plant. Leave, a resignation or a site repair call leaves finished pumps waiting in the bay, and machining and assembly start to slow because there is no space. Witness tests are booked with customers' inspectors weeks ahead, so a missed date can cost goodwill as well as time. Worse, a pump cleared by someone who could not read the curve properly may come back from site.

• Bench work is treated as the last step of assembly rather than as a skill in its own right.
• Test routines live in the lead's notebook, or in his head.
• The bench lead is also the person sent to fix pumps at customer sites.
• There is no grade for bench work, so juniors see no reason to stay on it.
• Borderline decisions are made quickly and never recorded, so nobody learns why a pump was passed or trimmed.

1. 1

   Write a test routine for each pump family

   Built by the bench team, not handed down. Rigging, valve sequence, readings to take, acceptance band agreed with design, and the common faults seen. The training page for pump makers covers how routines become a learning plan.

2. 2

   Bring on two more bench technicians

   Choose fitters who already show a feel for alignment and clearances. They run the bench under watch, then alone on standard pumps, then on specials.

3. 3

   Rotate them through witness tests

   The lead leads, the trainee runs the rig, and they swap once the trainee is ready. Customers' inspectors get used to more than one face.

4. 4

   Log every borderline call

   Pump number, reading, decision, reason and who decided. Over months, the log becomes the most useful training material the plant has.

5. 5

   Separate repair calls from the bench

   Assign a repair fitter or two for site calls and returned pumps, with cover planned, so the bench lead is not pulled away in a dispatch week.

6. 6

   Feed bench findings back to assembly

   A short monthly review of repeat faults such as seal leaks, high vibration or low head, traced to the build stage that caused them.

Date; pump model and serial number; customer.
What was borderline: head, flow, power, vibration, temperature or leakage.
Reading taken and acceptance band agreed with design.
Decision: pass, re-run, trim impeller, rebuild, or refer to design.
Reason in one sentence.
Decided by; checked by; trainee present.
Outcome after re-run or at site, if known.

Make bench technician a named grade with a band of its own. Put a lead grade above it for the person who runs witness tests and trains others. Compare those bands with what larger pump plants pay, using the pump plant pay benchmarking page. Measures for the bench should reward right-first-time clearance and fewer site returns, not just pumps tested per day, as the pump plant performance page explains. Younger operators who learn to program machines also get offers from bigger plants. A clear route from the machine shop to the bench and on to application work is one answer, covered on the pump makers' retention page.