Quality Control

Quality Control & Testing for Industrial Packaging Materials

Our packaging quality control covers every order of steel strapping, PET strapping, stretch film and strapping seals: checked at incoming material, during production and before packing, and shipped with an inspection report from our own lab in Changzhou.

How We Check

Four Quality Checkpoints, From Raw Material to Shipment

Packaging quality control at JUHONG runs at four checkpoints: incoming material, in-process checks every two hours, final sampling before shipment, and an inspection report with every order. Our quality system is certified to ISO 9001:2015, and every check follows a written procedure.

01
Raw material

Incoming Material Inspection

Steel coils, PET resin, LLDPE resin, paper cores and pallets are checked before they enter production.

02
On the line

In-Process Spot Checks

Inspectors take random samples from every line during production and measure them against the order specification.

03
Before packing

Final Inspection Before Packing

Finished coils and rolls are sampled again for dimensions and strength, and weighed.

04
At shipment

Inspection Report With Every Order

Each shipment leaves with a factory inspection report for that order.

Third-party testing, such as SGS, can be arranged for any order.

Steel Strapping

Steel Strapping Inspection

Steel strapping secures heavy loads such as steel coils and building materials, so it is tested for size and tensile strength at the raw coil, during production and before shipment.

01
Raw steel coil

Raw Steel Coil Inspection

Each incoming steel coil is checked for surface appearance, thickness and tensile strength. Its steel grade, chemical composition and mechanical properties are also checked against the supplier’s data.

02
Every two hours

In-Process Checks

Inspectors take 10 coils from the line and check width, thickness, tensile strength, bend performance, paint coating thickness on painted strapping and salt spray resistance of coated strapping. A failed bend or tensile result stops the line, and the last two hours of output are scrapped.

03
Before packing

Final Inspection & Coil Weight

Finished coils are sampled again for width, thickness and tensile strength, and weighed before packing. SGS tested our 19 × 0.8 mm steel strapping to the EN 13246 method: 1,082 MPa tensile strength and 14.5% elongation, for the sample tested.

Steel Strapping Tests We Run

Test 01
Tensile Strength

Strap samples are clamped in the tensile testing machine and pulled until they break.

Test 02
Bend Performance

Samples are checked for bend performance on our bend tester.

Test 03
Salt Spray

Coated strapping is checked for corrosion resistance in the salt spray chamber.

Test 04
Width & Thickness

Width and thickness are measured against the order specification and the tolerances below.

Test 05
Coil Weight

Finished coils are weighed on the floor scale and the weight is recorded before packing.

Steel Strapping Tolerances We Check

From our written steel strapping inspection procedure.

±0.10 mm
Width
±0.030 mm
Thickness, 0.4 mm strap
±0.035 mm
Thickness, 0.5–1.2 mm strap
≤ 6 mm
Camber per 2,000 mm
≤ 24 mm
Flatness
≤ 18°
Twist
406 ± 2 mm
Coil inner diameter
None
Welds in the coil
Strapping Seals

Strapping Seal Inspection

A seal is only as good as its grip on the strap, so seals are checked at the punch presses and again before shipment. JUHONG is one of the drafting organizations of GB/T 39040-2020, China’s national standard for steel seals and edge protectors for packing.

01
Steel strip & sheet

Incoming Steel

Steel strip and sheet for seals are bought in and checked on arrival for grade, size, surface and mechanical properties.

02
At the punch press

Punching Checks

Inspectors check punched seals against the drawing with calipers, and look for burrs, cracked edges and poor forming.

03
Painting & galvanizing

Coating Checks

Painted seals are checked for even coverage and colour. Galvanized seals go through a 24-hour salt spray test and a cross-cut adhesion test.

04
Before shipment

Final Check

Seals are sampled for size, appearance and coating, and the logo, packing and quantity are checked against the order before shipment.

Strapping Seal Tests We Run

Test 01
Dimensions

Seals are measured with calipers against the drawing.

Test 02
Punching & Forming

Edges and forming are checked at the punch press.

Test 03
Salt Spray

Galvanized seals are tested for 24 hours in the salt spray chamber.

Test 04
Joint Strength

A strap joint made with our seal is pulled on the tensile tester.

Seal Requirements We Check

From our written seal inspection procedures and GB/T 39040-2020, which we helped draft.

GB/T 39040
Seal dimension tables we check against
24 h
Salt spray test on galvanized seals
≤ 2 / 100
Cross-cut adhesion on galvanized seals, squares lifted
PET Strapping

PET Strapping Inspection

PET strapping is checked from the resin to the finished coil. Break strength depends on both the resin and the stretching process.

01
PET resin

Resin Inspection

Each batch of PET resin is checked against a colour sample, spread on white paper to spot black specks and impurities, and tested for viscosity before it is used.

02
Every two hours

In-Process Checks

Every two hours, inspectors take 10 coils from the line and check appearance, size and break strength. A failed break strength or elongation test stops the line, and the last two hours of output are scrapped.

03
Before shipment

Final Inspection & Report

Before shipment, 5 coils are taken at random from the batch and tested for break strength, elongation, size, camber and weight. If any sample fails break strength or elongation, the whole batch is rejected. The order ships with an inspection report.

PET Strapping Tests We Run

Test 01
Resin Viscosity

Each resin batch is tested for viscosity before it is used.

Test 02
Width

Strap width is measured with calipers.

Test 03
Thickness

Strap thickness is measured with a micrometer.

Test 04
Break Strength

Samples are pulled to break on the universal testing machine.

PET Strapping Tolerances We Check

Unless the order sets its own tolerances.

± 0.8 mm
Width tolerance
± 0.06 mm
Thickness tolerance
5% – 25%
Elongation at break
GB/T 22344
Minimum breaking load by size
≤ 150 mm
Camber per 2,000 mm, machine strap
± 3 mm
Coil width variation
Stretch Film

Stretch Film Inspection

Stretch film testing goes beyond thickness. A film can be the right gauge and still tear on a sharp pallet corner, so we also test puncture resistance and elongation.

01
Resin

Resin Appearance Check

Each batch of LLDPE resin is checked for appearance before it goes into production.

02
During production

In-Process Checks

Line operators record process readings during production. Inspectors take random samples and check film thickness and width, puncture resistance and elongation.

03
Before shipment

Final Sampling & Roll Weight

Before shipment, rolls are sampled and checked for appearance, size, tensile force, elongation at break and cling, and weighed. Each order ships with an inspection report.

Stretch Film Tests We Run

Test 01
Thickness & Width

Samples from the line are checked for thickness and width.

Test 02
Puncture Resistance

Film is loaded into the puncture fixture on our film tester.

Test 03
Elongation

A film strip is clamped in the tester grips and stretched to break.

Test 04
Roll Weight

Finished rolls are weighed before shipping.

Stretch Film Limits We Check

Checked to BB/T 0024-2018, China’s industry standard for stretch wrap film for transport packaging. If you need results to ASTM methods, testing can be arranged with a third-party lab.

± 6 mm
Width tolerance
± 10%
Average thickness vs. nominal (± 15% at any point)
± 1% / ± 2%
Roll net weight, hand film / machine film
± 2 mm
Core inner diameter
≥ 500% / ≥ 300%
Elongation at break (MD), machine pre-stretch / standard hand film
≥ 20 N / ≥ 10 N
Puncture force, machine pre-stretch / hand film
Bought-In Materials

We Inspect Bought-In Materials Too

Paper cores, pallets, cartons, paint and labels are checked when they arrive, so the materials around your strap and film meet the same standard.

Paper Cores

PET strapping cores are measured for inner and outer diameter and wall thickness. Stretch film cores are checked for wall thickness and weight, and go through a flat crush test.

Cartons

Board grade, print, size, fold and glue strength are checked.

Wooden & Plywood Pallets

Each batch comes with a fumigation report. Pallets are checked for mould, insects and rot, moisture content and size.

Paint, Wax & Pigment

Each batch needs a certificate and composition report, enough shelf life left, and no hardening.

Labels & Printed Packaging

Print content, barcodes and size are checked against the artwork.

Approved suppliers only

We buy from suppliers on our approved list, reviewed every year, and inspect a new supplier’s first samples before regular deliveries start.

Calibration & Traceability

Calibrated Gauges, Records & Traceability

A test result is only as good as the tool and the record behind it. Here is how we keep our checks accurate and every order traceable.

01

Calibrated Measuring Tools

Gauges and testers are calibrated on a fixed schedule, by accredited labs or against reference standards traceable to national standards. A tool past its date is tagged and taken out of use.

02

First-Piece Approval

The first pieces of every order, every shift and every machine restart after repair are approved by QC before production continues.

03

Records & Retained Samples

Inspection results are written on record sheets and kept on file. Samples from each batch are kept in the lab.

04

Nonconforming Product

Rejected product is held in a separate area, reworked and re-inspected, or scrapped.

05

Traceability Test

Twice a year we trace a shipped order back to its raw material batch, and a raw material batch forward to its shipments.

Independent Proof

Third-Party Testing & Certifications

Our in-house results can be confirmed by an independent lab. SGS or another third-party lab can test your order to the standard you name, including ASTM methods. Our quality management system is certified to ISO 9001:2015, and we hold AAR verification under AAR ID: AAR-124 for approved steel strapping and PET strapping products.

ISO 9001:2015
AAR ID: AAR-124
SGS test reports
GB/T 39040-2020

Packaging Quality Control FAQ

Yes. Every order ships with a factory inspection report for the products in that shipment.

Yes. Tell us the test items and the standard you need, including ASTM methods, when you order, and we will arrange testing by SGS or another independent lab.

Incoming steel coils are checked for appearance, thickness and tensile strength. Every two hours we take 10 coils from the line for width, thickness, tensile and bend tests, paint thickness and salt spray. Finished coils are checked again and weighed.

Samples are pulled to break on our universal testing machine during production and before shipment. If any sample fails break strength or elongation, the batch is rejected.

BB/T 0024-2018, China’s industry standard for stretch wrap film for transport packaging. Testing to ASTM methods can be arranged with a third-party lab.

Yes. Galvanized seals go through a 24-hour salt spray test and a cross-cut adhesion test.

Yes. Gauges and testers are calibrated on a fixed schedule, and any tool past its date is taken out of use.

Yes. Book a live video tour and we will run tests in the lab while you watch.

Samples & Test Reports

Request a Sample or Test Report

Want to check our strapping, film or seals against your own specification? Tell us the product, size, standard and tests you need, and we will send samples and a test report, or run the test while you watch on video.