A permanent mark can connect a finished composite insulator to its production batch, material records and final inspection. On silicone rubber sheds, however, a readable mark alone is not enough. The production team must establish that the chosen laser setting and location preserve the surface properties required by its own specification.
This buyer guide draws on Contune’s QHLM-20 fiber laser marking brochure and the current laser marker product page. The brochure describes marking directly on polymeric sheds. Its claim that marking has no effect on electrical, erosion or hydrophobic performance should be treated as a claim to verify on the actual compound and process, not a universal acceptance result.
Decide what to mark and where
Specify the data first: manufacturer, model, rated load, production date, serial or batch code and any purchaser-required identifier. Confirm which data belongs on the end fitting, housing or shed. A curved shed changes focus and character geometry; a metal fitting has a different response to the same laser. Send drawings of the largest and smallest products, marking location and permitted orientation with the RFQ.
Reference QHLM-20 configuration
| Brochure item | Published value |
|---|---|
| Laser type and power | Fiber laser, 20 W maximum output |
| Wavelength | 1064 nm |
| Marking field | 110 × 110 mm; 200 × 200 mm option |
| Published line width | 0.01–0.1 mm |
| Published depth range | 0.01–5 mm, material dependent option |
| Published scan speed | Up to 7000 mm/s |
| Electrical supply | 220 V, 50 Hz, 500 W |
| Cooling | Air |
These are machine brochure figures, not a validated recipe for silicone rubber. In particular, the optional depth range must not be interpreted as an acceptable shed engraving depth. Select power, speed, frequency and passes through trials on the actual formulation.
Qualify the mark on production material
- Prepare specimens from the actual silicone formulation and process, including the intended color and surface finish.
- Test a small parameter matrix and record power, speed, frequency, passes, focus distance and fixture position.
- Compare code contrast and readability immediately and after cleaning or handling.
- Inspect for excessive depth, heat damage, cracking, tackiness or loose residue.
- Where the product specification requires it, compare hydrophobicity, erosion or other surface properties with unmarked controls using an agreed test method.
- Approve a bounded parameter window and lock the production recipe.
Design the line station
A fixture should support different insulator lengths without bending the rod or deforming a shed. Confirm access to the selected mark area, focus repeatability, code rotation and cycle time across every SKU. Provide an enclosure or guarded station appropriate to the laser classification, extraction for marking fumes and particles, interlocks, emergency stop and operator instructions. Verify these controls against the local installation rules.
FAT and data traceability
Use actual insulator samples at FAT. Demonstrate the smallest and largest code, worst-case curvature, code changeover and repeatability after fixture reset. Scan or read every sample, check the match between printed code and production record, and document reject handling when a code is incomplete or duplicated. Request the parameter file, maintenance procedure, spare consumables and training record.
RFQ checklist
- Product drawing, housing material and colors
- Mark text, symbol or data-code format and minimum character size
- Allowed mark zone and prohibited surfaces
- Production takt time and number of SKUs
- Code source and connection to MES or batch records
- Qualification method for contrast and housing integrity
- Laser enclosure, extraction, power supply and line footprint
Marking is one part of the manufacturing route. For upstream end-fitting selection, see our CTCPM crimping machine selection guide.
FAQ
Can the published 7000 mm/s be used as the production cycle time?
No. It is a maximum scanning speed. Total cycle time also includes loading, positioning, focus, marking, verification and unloading.
Does a visible mark prove that shed properties are unaffected?
No. Qualification requires tests on the actual housing material and agreed acceptance criteria.