The settling chamber and the main gear oil sump have different maintenance records. A note saying “oil changed” does not show whether accumulated water was drained from the chamber or whether its sediment was removed. This guide helps document those two chamber tasks without prescribing a disassembly procedure.
What the NOV booklet says
Page 6 of NOV document 25-101131 locates the lubricant settling chamber below the crossheads and ahead of the oil sump. Its purpose is to separate water and contaminants from the gear oil. The booklet identifies clean-out plates and drain plugs on both sides of the pump.
The cited passage specifies weekly drainage of accumulated water through the drain plug. It separately calls for opening the clean-out plates and thoroughly clearing sludge and sediment from the chamber during routine power-end oil changes. These are two distinct activities: a drainage entry does not demonstrate that sediment cleaning was completed.
Confirm the current manual and the installed configuration before scheduling or carrying out work. This summary is not permission to open a running pump. Authorized maintenance personnel must follow the applicable shutdown, energy-isolation, safe-access and fluid-handling procedures. The cited passage alone does not establish a complete safe-work method, a plug torque, a seal specification or an oil-change interval.
Suggested maintenance record
The following fields are editorial suggestions for traceability, not additional manufacturer requirements:
- Pump model, serial number, equipment tag and applicable manual revision.
- Task type: scheduled water drainage or chamber cleaning associated with an oil change.
- Date, work-order number and the responsible maintenance person.
- The actual chamber access or drain location used, identified on the installed pump.
- Observed discharge or deposits, described without an unsupported diagnosis; record “not observed” where appropriate.
- For cleaning, the areas checked and any remaining deposit or inaccessible area requiring review.
- Completion of the applicable closure and return-to-service checks, recorded by the responsible person under the site procedure.
- Any incomplete work, follow-up work order and next due date under the approved maintenance schedule.
Record the two tasks separately even if they occur during the same stoppage. Do not enter “chamber cleaned” solely because a drain plug was opened. If an observation was not made, leave that limitation visible instead of filling in a normal result.
Interpret the record within its limits
Water or sludge in the record is an observation, not proof of the entry path or a failed component. Repeated findings should be referred for maintenance investigation using equipment history and the applicable procedure. Do not infer a repair, an oil grade or a universal rejection threshold from this checklist.
The same manual page discusses cleaning the main gear oil sump separately. Keep that work identifiable on the work order: a chamber record cannot stand in for the sump task, and a sump entry cannot establish that the chamber was cleaned. Retain unresolved items through handover until the responsible person records the disposition.
Equipment and related records
Use the NOV 12-P-160 and NOV 14-P-220 pages for equipment navigation. These links do not prove shared drain plugs, seals or replacement parts. For a different observation task, use the power-end oil-level record; a stable dipstick reading does not establish chamber cleanliness.
Source and scope
NOV, How to Treat Your Type P Triplex Mud Pump, document 25-101131, page 6, checked 29 September 2026, Beijing time. The location, chamber function and two maintenance timings above come from the booklet. Record fields and handover advice are editorial suggestions. No part interchangeability, cleaning chemical, service-life claim or complete operating procedure is established here.
FAQ
Is weekly drainage the same as chamber cleaning?
No. The booklet distinguishes drainage of accumulated water from removal of sludge and sediment during routine power-end oil changes.
Does this article set the oil-change interval?
No. Obtain the applicable oil-change schedule from the current equipment instructions and approved site maintenance programme.
Does water in a record identify the failed part?
No. It documents an observation; the cause requires investigation rather than an assumed component diagnosis.
Can the main sump record replace the chamber record?
No. Identify both tasks separately so a completed entry for one does not conceal unfinished work on the other.