Problem this solves
You need a replacement seal but only have the old unit. Use these steps to measure ID, OD, width, and lip profile for verified specifications.
Step-by-step measurement
- 1Clean the seal and note any markings or part numbers.
- 2Measure the shaft diameter (seal ID) with a caliper.
- 3Measure the housing diameter (seal OD).
- 4Measure the seal width across the metal case.
- 5Identify the lip type: single or double, spring or no spring.
- 6Record media, temperature, and shaft speed if known.
Common oil seal profiles
| Profile | Lip style | Typical use |
|---|---|---|
| TC | Double lip with spring | General rotary shafts |
| SC | Single lip with spring | Lower contamination |
| TB | Double lip, no spring | Grease retention |
| VC | Heavy duty dust lip | Dirty environments |
Include When Confirming Specifications
- ID / OD / width in mm
- Lip profile (TC/TB/SC) and spring details
- Material choice (NBR/Viton/PTFE)
- Media and temperature range
- Photo of the old seal with markings
ID × OD × W notation examples
| Example | What it means | Notes |
|---|---|---|
| 25 × 47 × 7 mm | ID 25, OD 47, width 7 | Common metric format |
| 30 × 52 × 7 mm | ID 30, OD 52, width 7 | Verify lip type (TC/SC) |
| 35 × 52 × 7 mm | ID 35, OD 52, width 7 | Confirm housing bore |
| 1.000 × 2.000 × 0.250 in | ID 1.000, OD 2.000, W 0.250 | Inch example only |
SC vs TC lip types (why it matters)
SC is a single-lip seal for cleaner duty. TC adds a dust lip for contamination control. Always match the lip style to the environment and shaft condition.
Common measurement pitfalls
- Measuring a deformed or worn seal instead of the shaft/housing
- Mixing ID and OD due to caliper angle or misalignment
- Skipping the width measurement or lip profile
- Not noting spring-loaded vs non-spring
- Ignoring shaft wear or grooves that require a sleeve
Fastest quote tip
Send a clear photo of the seal face plus your ID/OD/width measurements for the fastest confirmation.
Related resources: unknown node • unknown node • unknown node • unknown node