WB Tape Specs: Grade Check

Compare WB tape specs by units and methods. Water blocking tape specifications help cable buyers screen candidate grades, but rows from different datasheets are not automatically comparable. Function, units, tolerances, test conditions and roll format must match the intended cable layer. Carry the data into a controlled line trial and applicable finished-cable qualification.

Conceptual material and swelling visualization; not a Chaowang product photograph or test record.

Water Blocking Tape Specifications Begin with the Correct Function

First classify the layer. A non-conductive tape, a semi-conductive water-blocking tape and an ordinary binding tape may all use fibrous carriers, yet they do not have the same electrical or swelling duty. Also state whether the design requires a single-side or double-side swelling construction. Comparing thickness before confirming these functions can produce a technically invalid shortlist.

Jiangsu Chaowang New Material identifies CW-5 non-woven water blocking tape as polyester non-woven fabric, superabsorbent resin and adhesive, with published single-side and double-side grade families. Its public table lists grade-specific values for mass, thickness, tensile strength, elongation, moisture, expansion and temperature stability. Request the current controlled datasheet for the exact grade.

• Intended layer: record whether the tape will sit around a cable core, over another defined layer or in a longitudinal application allowed by the cable drawing.
• Electrical duty: do not infer semi-conductive behavior from the phrase “water blocking.” If conductivity is required, specify the relevant electrical property and method separately.
• Construction: freeze single-side or double-side format and the orientation required during loading and application.

The wider Chaowang non-woven cable tape range helps keep these duties separate. For example, CW-1 non-woven binding tape is presented for cable-core binding; it should not be assigned a water-swelling function that its published specification does not claim.

Read Thickness, Mass, Tensile Strength and Elongation as a Set

A useful comparison sheet preserves each supplier’s unit, test method, tolerance and reporting convention. Separate nominal values from minimums, maximums and typical values. A “0.25 mm” entry without tolerance, contact pressure or test method does not carry the same evidence as a controlled thickness range.

Conceptual laboratory arrangement; instruments are illustrative and show no Chaowang test result.

• Mass per unit area: compare in the same unit, normally g/m², and retain the stated tolerance. It is not a substitute for thickness.
• Thickness: check nominal value, tolerance and measurement method because compressible non-woven structures respond to contact pressure.
• Tensile strength: confirm the unit, specimen direction and minimum requirement. The value should support stable converting and application without being treated as cable tensile strength.
• Elongation: read it with tensile strength and the same test direction; neither row alone predicts tracking, wrinkling or break behavior on the customer’s line.

Do not “correct” a supplier table by converting a minimum into a nominal or by dropping tolerances. If two candidates use different methods or specimen conditions, mark the rows as not directly comparable and request aligned data or representative samples.

Compare Swelling Speed and Height Under Identical Conditions

Swelling speed describes an early response over a stated interval; swelling height describes the developed rise after a stated time. The two rows answer different questions. They also depend on the test liquid, specimen preparation, conditioning, temperature, fixture, reading time and whether the tape is free or confined. Therefore, a larger number from an unmatched method is not proof of better cable performance.

Ask the supplier to state the complete method behind entries such as mm/min or mm/3 min. Record the material’s moisture condition before testing, because storage and conditioning can affect a swellable system.

Turn Datasheet Rows into a Purchase and Cable Qualification Record

A purchase specification should identify the approved grade and revision rather than repeat only a generic tape name. Add slit width and tolerance, roll outside diameter, core inside diameter, winding direction where relevant, maximum joints, identification, packaging and the properties required on the lot certificate. Agree how changes in carrier, absorbent system, adhesive, method or production location will be communicated.

1. Document review: compare the current TDS, safety information where applicable, sample identification and proposed certificate of analysis fields.
2. Sample trial: record payoff, tracking, tension, overlap or longitudinal placement, visible dusting, breaks and the condition after the next manufacturing step.
3. Material verification: check the agreed rows using the same methods and conditioning stated in the approval plan.
4. Cable evidence: apply the relevant finished-cable water-penetration method and acceptance criterion for the cable type and customer specification.

Conceptual cable-level test apparatus; not an exact standard setup or a finished-cable test result.

For optical cables, IEC 60794-1-22:2017 includes Method F5. As of 2026-10-28, IEC 60794-1-205:2026 was an FDIS pre-release for a dedicated F5 document; confirm final publication and contract edition before use. ITU-T L.101 also treats longitudinal water penetration as a cable-level characteristic. None of these sources converts a tape coupon result into cable compliance.

The existing CW-5 construction and grade guide provides grade-family context, while the incoming lot-release guide covers receipt checks. Use this article specifically to build a comparable pre-purchase datasheet matrix and controlled approval record.

Frequently Asked Questions

Which water blocking tape specifications should appear on an RFQ?

State the functional type, single-side or double-side construction, intended cable layer, thickness and tolerance, mass per unit area, tensile and elongation requirements, swelling method and limits, moisture limit, slit width, roll and core dimensions, joints, packaging and lot-certificate fields. Add electrical properties only when the layer actually requires them.

Is a higher swelling height always better?

No. The available cavity, compression, adjacent materials and cable geometry determine how much expansion is useful. Excess build may affect processing or the next layer, while insufficient contact can leave a path. Compare results obtained by the same method, then validate the chosen tape in the intended construction.

Can mm/min be compared directly with mm/3 min?

No. One commonly describes an early swelling rate and the other a height after a stated interval. The fixture, liquid, conditioning and reading procedure must also match. Preserve each result with its complete method instead of converting between the values through simple arithmetic.

Does “non woven water blocking tape” mean non-conductive?

Not automatically. “Non woven” identifies the carrier form, not the electrical classification. A cable screen interface may require defined surface or volume resistance, while another layer may require non-conductive behavior. Confirm the intended electrical duty and request the applicable values before approving a grade.

Should roll dimensions be part of the technical specification?

Yes. Slit width, core inside diameter, roll outside diameter, length, winding quality and joints affect equipment compatibility, changeover frequency and continuous running. Two tapes with similar coupon properties may behave differently operationally if their roll format does not fit the payoff or process window.

Does a compliant datasheet prove finished-cable water blocking?

No. A datasheet describes material properties under stated conditions. Finished-cable performance also depends on placement, seams, overlap, compression, void geometry, joints, manufacturing damage and the completed construction. Run the applicable cable-level water-penetration test when the product standard or customer specification requires it.

To review water blocking tape specifications for a new cable, send Jiangsu Chaowang New Material the cross-section, intended CW-5 layer, electrical classification, target width and roll format, line conditions and required cable test. Request the current controlled datasheet, lot-certificate format and a representative sample before approval.