# Oil Analysis Sample Log Worksheet

> Source: https://netray.co/tools/oil-analysis-sample-log-worksheet
> Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems.
> Section: Free Tools

## Short answer

An editable log for oil samples with viscosity change calculated per row, water and iron readings, and an action column. Exports to Excel.

## Category

maintenance

## Industry

Manufacturing

## Audience

- Reliability engineer
- Lubrication technician
- Maintenance planner

## Tool

**Kind:** worksheet

**Mode:** editable

**Columns:**

#### Sample date

**Key:** date

**Type:** date

#### Asset

**Key:** asset

**Type:** text

#### Oil grade

**Key:** oil

**Type:** text

#### New oil viscosity at 40C

**Key:** base_visc

**Type:** number

**Unit:** cSt

**Format:** decimal

#### Sample viscosity at 40C

**Key:** visc

**Type:** number

**Unit:** cSt

**Format:** decimal

#### Viscosity change

**Key:** visc_chg

**Type:** number

**Expr:** if(gt(base_visc,0),(visc - base_visc) / base_visc * 100,0)

**Format:** percent

#### Water

**Key:** water

**Type:** number

**Unit:** ppm

**Format:** integer

#### Iron

**Key:** iron

**Type:** number

**Unit:** ppm

**Format:** integer

#### ISO 4406 code

**Key:** iso

**Type:** text

#### Action

**Key:** action

**Type:** select

**Options:**

- None
- Resample
- Filter
- Change oil
- Inspect machine

**Rows:**

**Date:** 2026-09-02

**Asset:** GBX-12 Gearbox

**Oil:** ISO VG 220

**Base visc:** 220

**Visc:** 228

**Water:** 140

**Iron:** 18

**Iso:** 18/16/13

**Action:** None

**Date:** 2026-09-02

**Asset:** HYD-03 Press hydraulics

**Oil:** ISO VG 46

**Base visc:** 46

**Visc:** 44.1

**Water:** 310

**Iron:** 9

**Iso:** 20/18/15

**Action:** Filter

**Date:** 2026-09-09

**Asset:** CMP-07 Compressor

**Oil:** ISO VG 68

**Base visc:** 68

**Visc:** 77.5

**Water:** 90

**Iron:** 6

**Iso:** 17/15/12

**Action:** Resample

**Date:** 2026-09-16

**Asset:** GBX-15 Gearbox

**Oil:** ISO VG 320

**Base visc:** 320

**Visc:** 335

**Water:** 520

**Iron:** 74

**Iso:** 21/19/16

**Action:** Inspect machine

**Date:** 2026-09-23

**Asset:** TRB-02 Turbine bearing

**Oil:** ISO VG 32

**Base visc:** 32

**Visc:** 32.4

**Water:** 60

**Iron:** 3

**Iso:** 16/14/11

**Action:** None

**Totals:**

#### Average viscosity change

**Key:** visc_chg

**Agg:** avg

**Format:** percent

#### Highest water

**Key:** water

**Agg:** max

**Format:** integer

#### Highest iron

**Key:** iron

**Agg:** max

**Format:** integer

**Notes:** Limits depend on the oil, the machine and your lab. A change of about 10% in viscosity is a common trigger for investigation, and water limits are tighter for hydraulic and turbine systems. Use your lab report limits and OEM guidance rather than the example rows.

## Content

**Intro:** Oil analysis labs email you PDFs, but nobody trends PDFs. This worksheet gives you one editable table where every sample for every asset sits next to the new oil baseline, so a drift in viscosity or a rising iron count is visible at once.

**Sections:**

#### How to use the worksheet

**Body:** Add one row per sample. Enter the new oil viscosity from the product data sheet and the sample viscosity from the lab. The viscosity change column is calculated for you. Add water, iron and the ISO cleanliness code straight off the report, choose an action, and export to Excel to sort by asset or filter by action. Keep the file as your working register and file the lab PDFs alongside it.

**Bullets:**

- Use the same asset names as your CMMS equipment list
- Always take samples from the same port at the same operating state
- Log the oil top-ups elsewhere so viscosity changes are explainable

#### What the numbers tell you

**Body:** Viscosity change is calculated as sample minus new oil, divided by new oil. A rise usually means oxidation, evaporation of light fractions or contamination with a heavier oil. A fall points to fuel dilution, shear of polymer additives or mixing with a thinner product. Water in ppm shows seal or breather problems. Iron suggests wear of gears, shafts or cylinders. The ISO 4406 code reports particle counts at three sizes and shows how clean the system is.

#### Setting limits

**Body:** Start with the lab limits and the machine OEM, then tighten as you build history. Many reliability programs set a caution and a critical value per test and use the Action column to record what was done. Trend direction matters as much as the level: iron that doubles in two samples deserves a look even if it is under the printed limit.

#### Common mistakes

**Body:** Common errors include sampling right after an oil change, mixing sample points, ignoring contamination codes because viscosity looks fine, and letting reports pile up with no action recorded. Another is comparing the sample viscosity with the wrong baseline grade. Put the correct new oil values in every row.

**Cta:** Netray can help pull oil analysis results into your ERP maintenance module so action items become work orders rather than spreadsheet rows.

**Faq:**

#### Do I need a lab to use this worksheet?

**Answer:** The log works with any source of results: a commercial lab, an in-house viscometer or a patch test kit. You only need to fill the columns you have. Blank cells for water or iron do not break the calculation of viscosity change.

#### What viscosity change should trigger action?

**Answer:** There is no universal number. Many programs investigate when viscosity shifts by about 10% from new oil and treat 20% as critical for most industrial oils. Check your lab and OEM guidance for the specific machine.

#### Can I add more columns?

**Answer:** Export to Excel and add columns such as TAN, additive elements or sample interval. The online table keeps the common fields so it stays quick to fill on a phone or tablet.

#### How often should I sample?

**Answer:** Critical gearboxes and turbines are often sampled monthly or quarterly, general hydraulics quarterly or every six months. Shorten the interval when a trend moves.

## Search terms

oil analysis log excel, oil sample tracking spreadsheet, lubricant analysis template, oil analysis report tracker, used oil analysis worksheet, viscosity change percent calculator, lubrication condition monitoring log

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