Who This Checklist Is For
If you're responsible for buying, installing, or approving a Weir slurry pump (or any heavy-duty mining pump), this list is for you. Specifically:
- Mining engineers writing specs
- Procurement teams evaluating proposals
- Site supervisors signing off on installations
I review roughly 200+ pump-related deliverables a year—specifications, inspection reports, installation checklists. Over four years of this, I've developed a shortlist of things I always verify before signing off. This is that list.
Seven steps. Each one has bitten me at least once. Skip at your own risk.
Step 1: Verify the Model Number Against the Duty Sheet
Sounds obvious. You'd be surprised how often it gets missed.
The duty sheet from the process engineer says you need a Weir Warman® AH model for that slurry loop. The vendor quotes, and later delivers, a Warman® MCR. Both are good pumps. The MCR might even be cheaper. But it's not the pump the system was designed around.
What I check: I literally compare the model number stamped on the pump's nameplate against the approved-for-construction duty sheet. Not the PO. Not the quote. The duty sheet.
If I remember correctly, I caught a mismatch about three years ago—an MCR delivered when the spec called for an AH. The vendor claimed they were 'equivalent enough.' They weren't. The impeller trim was different. The hydraulic performance curve shifted by about 4% at the design flow rate. We rejected the pump. That decision cost us a week in schedule but saved a potential year of underperformance.
Step 2: Check the Casing Hardness (Not Just the Material Grade)
Most specs say 'Grey Iron' or 'High Chrome' for the casing. But the material grade alone doesn't tell you the wear life.
What I check: I ask for the certified hardness test report for the casing. For a typical Weir slurry pump handling abrasive tailings, we expect a minimum of 550 HB in the high-chrome wear parts. I've seen casings delivered at 480 HB—within the 'High Chrome' grade spec, but soft enough that you'll lose 20-30% of your expected wear life.
In our Q1 2023 quality audit, we rejected 15% of first deliveries from one casting supplier due to insufficient hardness. They claimed it was 'within industry standard.' We showed them our spec. They redid the castings at their cost.
Step 3: Confirm the Stuffing Box Clearances
This is the one most people overlook. The stuffing box is where the shaft enters the pump casing. The clearance between the shaft sleeve and the packing (or mechanical seal) is critical.
What I check: The gap should be per Weir's specification for that model. Too tight, and the packing will overheat and fail prematurely. Too loose, and you get excessive leakage and air ingress.
I once approved a pump where the clearance was 0.015 inches over the maximum spec. The installer said it 'felt fine.' Within 200 hours of operation, the packing started leaking. Replacing it took three hours of downtime. Total cost: about $800 in packing material plus the lost production. (I should note that was on a smaller pump—the downtime cost on a main sump pump handling slurry feeds would be a different story entirely.)
Step 4: Measure the Impeller-to-Volute Gap (The 'Cutwater' Check)
This is the gap between the impeller vanes and the volute liner. It directly affects pump efficiency and vibration.
What I check: I use a feeler gauge to check the gap at three points around the circumference. The spec usually calls for a gap within a few millimeters, model-dependent. If the gap is uneven—say 4 mm on one side and 6 mm on the other—you'll get unbalanced hydraulic forces. That means higher bearing loads, more vibration, and potentially reduced seal life.
In my experience, this is the most common root cause of early bearing failure in new slurry pumps. People chase bearing quality or lubrication, but the real problem is a misaligned impeller from day one.
Step 5: Verify the Flange Drilling Pattern
This one is more painful than it should be. You'd think a 6-inch ANSI 150 flange is a 6-inch ANSI 150 flange. The bolt circle diameter and number of bolts are standard. Weir pumps come with flanges that match the standard.
What I check: I measure the bolt circle diameter and count the bolts. But—and this is the detail—I also check the stud length specified in the piping drawing. Sometimes the pump flange face is thicker than expected, and the standard studs are too short to get full thread engagement.
I rejected a batch of pumps three years ago because the supplied studs were 25 mm too short. The vendor argued their studs were 'standard.' Standard for a generic flange, maybe. Not standard for the specific flange face thickness on that pump model. We specified the correct stud length in the contract, and they replaced them.
Step 6: Inspect the Baseplate Level and Grouting
The pump arrives on a steel baseplate. The baseplate gets grouted into the foundation. This is a step everyone assumes will be done correctly on site. I've learned not to assume.
What I check: Before the grout is poured, I verify the baseplate is level within 0.002 inches per foot of length. I also check that the grout pads are properly chamfered and that the grout is a non-shrink, epoxy-based type—not the cheap cementitious stuff some contractors try to use.
We had a case where a contractor used a cementitious grout on a main slurry pump baseplate (ugh). Within six months, the grout had cracked, the baseplate shifted, and the alignment between the pump and motor was out by 0.010 inches. That caused coupling wear and vibration. The fix: removing the pump, chip-casting the grout, and repouring with epoxy. That was a $18,000 project, all because someone wanted to save $200 on grout.
Step 7: Run a No-Load Test (And Listen)
Before connecting any pipes, I run the pump for a short period with no load—just the motor driving the pump with the suction and discharge valves closed (or with a temporary bypass loop).
What I check: I listen for any unusual sounds. A healthy slurry pump should make a steady, low-frequency hum. What I'm listening for is anything high-pitched, intermittent, or metallic.
I remember one instance where we heard a scraping sound during a no-load test. Turned out the impeller was slightly misaligned and rubbing against the front liner. The clearance was about 0.5 mm less than spec. We pulled the pump, adjusted the impeller position, and the noise disappeared. If we'd skipped the no-load test and connected the pipes, that misalignment would have worn through the liner within weeks.
Common Mistakes and What to Watch For
Mistake 1: Assuming 'Brand New' Means 'In Spec'
It's tempting to think a new Weir pump from a reputable dealer will be perfect. I've seen new pumps with incorrect impeller trims, wrong gasket materials, and missing drain plugs. Trust, but verify.
Mistake 2: Rushing the Foundation Curing
Epoxy grout needs 24-48 hours to cure fully. I've seen crews pour the grout in the morning and start aligning the pump by afternoon. The grout hasn't developed full bond strength yet. Wait the full cure time. It's not worth the risk.
Mistake 3: Over-Tightening the Packing Gland
New packing needs to be adjusted after initial operation. Over-tightening a dry or under-lubricated packing can score the shaft sleeve. Run the pump, let the packing wear in, then adjust the gland nuts to achieve a controlled drip (typically 5-10 drops per minute).
Final thought
I used to think that as long as the pump was the right model, it would work. That might be true for a simple water pump. For a Weir slurry pump handling abrasive tailings or concentrated minerals? The details matter. The hardness of the casing, the clearance in the stuffing box, the level of the baseplate—those millimeters and degrees add up to uptime versus downtime.
The checklist above won't guarantee perfection. But it'll catch about 90% of the common issues I see. If you follow it, you'll likely avoid the most expensive installation mistakes. (Note to self: update this list next year when the new model specs drop.)