The Technical Vault
By SOSCleanroom
KIMBLE 13500-3
3 mm Diameter
Borosilicate Glass 3.3
Solid Glass Beads
1 lb Container
Approx. 12,000 Beads
KIMBLE 13500-3: solid glass packing for laboratory distillation and mixing
KIMBLE® 13500-3 is a 3 mm solid borosilicate glass packing bead manufactured by DWK Life Sciences. The beads belong to the KIMAX® laboratory glass product line and are intended for use as distillation column packing, mixing beads, or boiling stones in suitable laboratory applications.
The manufacturer specifies borosilicate glass 3.3, a 3 mm nominal diameter, and a ±0.3 mm dimensional tolerance. Each one-pound container provides approximately 12,000 beads, representing about 360 cm³ of bulk volume.
Operations takeaway: Select glass packing beads as part of the complete laboratory process. Bead diameter, column geometry, chemical compatibility, temperature conditions, packing arrangement, and required cleanliness all influence suitability. A material specification alone does not establish separation performance or qualification for a regulated process.
Specifications (SKU controls for purchasing, SOPs, and receiving)
- Manufacturer: DWK Life Sciences
- Brand: KIMBLE® / KIMAX®
- Catalog Number: 13500-3
- Product Family: 13500 Distillation Column Packing Beads
- Material: Borosilicate glass 3.3
- Construction: Solid spherical glass beads
- Nominal Diameter: 3 mm
- Diameter Tolerance: ±0.3 mm
- Beads per Cubic Inch: Approximately 550
- Beads per Pound: Approximately 12,000
- Package Quantity: 1 lb (approximately 0.45 kg)
- Approximate Bulk Volume: 360 cm³ (22 cubic inches)
- Case Quantity: 1 container
- Manufacturer-Listed Applications: Mixing beads, boiling stones, and distillation column packing
Specification control: The published bead counts and volume are approximate values. For purchasing and receiving, identify the complete manufacturer number 13500-3 rather than relying only on the description "glass beads."
Borosilicate glass 3.3: construction and material properties
The beads are manufactured from borosilicate glass 3.3, a glass composition with relatively low thermal expansion and high chemical durability. The designation 3.3 refers to the approximate coefficient of linear thermal expansion of this glass material, expressed as 3.3 × 10-6 K-1 over the manufacturer's stated reference temperature interval.
DWK's glass material guide identifies 3.3-expansion borosilicate glass as resistant to water, many acids, salt solutions, halogens, and organic solvents. The glass differs in composition and thermal expansion behavior from conventional soda-lime laboratory glass.
- Glass Type: 3.3-expansion borosilicate glass
- Thermal Expansion: Approximately 3.3 × 10-6 K-1 (20–300°C), as a general material property
- Hydrolytic Resistance: DWK lists Class HGB 1 according to ISO 719 for 3.3 glass
- Acid Resistance: Class S1 under DIN 12116 for the general glass material
- Alkali Resistance: Class A2 under ISO 695 for the general glass material
- Material Standards: DWK lists ASTM E438 Type I Class A and USP Type I glass classifications for 3.3-expansion borosilicate glass
Material classification boundary: These are published properties and classifications of the 3.3 glass material. They are not individual lot test results, a product-specific performance certificate, or proof that packaged 13500-3 beads have been qualified for a particular pharmaceutical or analytical application.
Review DWK's Glass Types & Properties technical reference
Chemical compatibility: where borosilicate glass performs well and where it does not
DWK describes KIMAX® glass beads as highly resistant to attack by most hot or cold liquids and vapors. The manufacturer's general glass guide supports broad chemical durability for 3.3-expansion borosilicate glass, but also identifies important exceptions.
| Chemical environment |
Selection consideration |
| Water and many aqueous solutions |
Generally good chemical durability for borosilicate glass 3.3 |
| Many organic solvents |
Generally compatible, subject to process conditions and contamination requirements |
| Many common acids |
Good resistance, with important chemical and temperature exceptions |
| Hydrofluoric acid |
Attacks silica-based glass; do not assume compatibility |
| Hot concentrated phosphoric acid |
DWK identifies appreciable glass corrosion under these conditions |
| Strong alkaline solutions |
Can attack glass, particularly with elevated temperature or extended exposure |
Compatibility checkpoint: Determine compatibility using the actual chemical formulation, concentration, temperature, exposure duration, and acceptable extractables or surface-change limits. General resistance information is not a guarantee of suitability for every laboratory procedure.
How glass bead packing works inside a fractionating column
Fractional distillation separates liquid mixtures through repeated vapor-liquid equilibration. In a packed column, rising vapor contacts liquid flowing downward through the packing. The packing provides surfaces and pathways for heat and mass transfer between the two phases.
Solid spherical beads produce an arrangement of glass surfaces and interstitial spaces. The effectiveness of this arrangement depends on the column's geometry, packing distribution, wetting conditions, operating flow rates, and vapor-liquid equilibrium of the mixture.
- Vapor-liquid contact: Bead surfaces provide potential contact locations for descending liquid and rising vapor.
- Interstitial flow: Voids between the beads allow liquid and vapor to pass through the column.
- Liquid distribution: Packing arrangement and wetting affect how liquid travels across the bed.
- Pressure drop: Flow resistance is affected by bead dimensions, packed-bed height, and operating conditions.
- Separation efficiency: Depends on the combined effects of packing, column design, and process operation.
DWK's published 13500-3 specifications do not establish a theoretical plate count, height equivalent to a theoretical plate (HETP), maximum vapor loading, flooding limit, or a quantitative pressure-drop curve.
Bead diameter, packing geometry, and column performance
Smaller spherical beads generally provide more geometric surface area per unit of solid packing volume than larger spheres. However, increasing surface area does not automatically improve a distillation process because vapor flow resistance, wetting, channeling, and flooding behavior may also change.
- Internal column diameter: Check that the packing is appropriately sized relative to the column geometry.
- Retention components: Confirm that the screen, frit, or other support retains 3 mm beads.
- Bed height: Establish an appropriate packing depth for the apparatus and separation requirements.
- Packing arrangement: Avoid obstructions, excessive compaction, or visibly uneven distribution.
- Operating rates: Evaluate the actual vapor and liquid flow conditions.
- Material selection: Determine whether borosilicate glass is compatible with all process chemicals and expected operating conditions.
Engineering takeaway: A 3 mm nominal bead size is a purchasing and geometry specification, not a guaranteed distillation performance rating. Evaluate packing performance at the system level.
KIMBLE 13500 series: comparison of verified bead sizes
DWK lists four nominal bead diameters in the KIMBLE® 13500 family. Each size has its own catalog number, diameter tolerance, and approximate bead count.
| DWK SKU |
Diameter |
Tolerance |
Beads / in³ |
Beads / lb |
| 13500-3 |
3 mm |
±0.3 mm |
550 |
12,000 |
| 13500-4 |
4 mm |
±0.4 mm |
250 |
5,200 |
| 13500-5 |
5 mm |
±0.5 mm |
125 |
3,000 |
| 13500-6 |
6 mm |
±0.6 mm |
75 |
1,800 |
All bead counts are approximate manufacturer values. The different diameters are separate products, not interchangeable substitutions guaranteed to deliver equivalent process performance. Confirm pricing and availability with SOSCleanroom.
Mixing beads and boiling stones: additional manufacturer-listed applications
In addition to distillation packing, DWK identifies these solid glass beads for laboratory mixing and boiling applications. The appropriate use depends on the vessel, liquid properties, equipment, and laboratory method.
- Mixing applications: Solid beads may provide mechanical mixing assistance in suitable vessel and agitation configurations.
- Boiling applications: May be used as boiling aids when their surface characteristics and the laboratory procedure are appropriate.
- Laboratory research: May be evaluated wherever solid 3 mm borosilicate glass spheres are required and compatible.
Heating safety: Do not add boiling aids to hot or superheated liquid. Solid glass beads are not automatically equivalent to porous boiling chips or other specialized anti-bumping products.
Sterility, cleaning, thermal processing, and reuse
The reviewed manufacturer listing does not establish that KIMBLE® 13500-3 beads are supplied sterile, nor does it specify a validated product-specific autoclave cycle, depyrogenation procedure, or maximum number of reuse cycles.
Borosilicate glass 3.3 is generally resistant to thermal stress compared with ordinary soda-lime glass, but the physical material properties do not establish a finished-product temperature limit or validated sterilization procedure for this specific package of beads.
- Cleaning: Use an approved procedure compatible with the glass material and the contaminants involved.
- Rinsing: Select a suitable rinse quality for the intended process, particularly in analytical applications.
- Drying: Follow laboratory procedures that minimize contamination and avoid damaging thermal gradients.
- Sterilization: Establish a validated process when the intended use requires sterile materials.
- Reuse: Verify physical condition, residual contamination, and compatibility before returning used beads to service.
- Traceability: Maintain product identity, preparation records, and lot information according to facility requirements.
Processing boundary: Do not assume the packaged beads are sterile, endotoxin-controlled, validated for autoclaving, or certified for a particular cleanliness level without supporting product-specific manufacturer documentation.
Cleanroom suitability and contamination-control considerations
Although SOSCleanroom supplies products for controlled environments, the reviewed DWK listing does not establish that this particular glass bead product is cleanroom processed, cleanroom packaged, or suitable for a specific ISO classification.
- ISO cleanliness rating: No SKU-specific rating identified.
- Supplied sterility: Not established.
- Particle cleanliness: No quantitative particle specification identified.
- Endotoxin control: No product-specific endotoxin limit identified.
- Low-extractable requirements: General material properties are not a substitute for process-specific extractables evaluation.
- Application suitability: Determine through the facility's documented qualification and material-introduction procedures.
For sensitive analytical or regulated applications, evaluate cleaning requirements, handling controls, chemical compatibility, potential particulate generation, and any required manufacturer documentation before use.
Storage, handling, and preparation controls
- Protect from contamination: Keep containers closed and store beads away from unnecessary dust, debris, and chemical exposure.
- Avoid impact damage: Handle carefully to prevent chipped or fractured glass.
- Control transfer: Use clean laboratory tools when dispensing beads into process equipment.
- Maintain size segregation: Prevent unintended mixing of different bead diameters.
- Record preparation: Document cleaning, rinsing, drying, and other preparation activities when required by the laboratory.
- Evaluate reuse: Inspect previously used beads before any authorized reuse.
No finished-product shelf life or specific storage temperature range was identified in the reviewed manufacturer listing. Establish additional controls where necessary for the intended application.
Packaging, receiving, and inspection checklist
DWK identifies the 13500-3 configuration as one 1 lb container containing approximately 12,000 solid glass beads. Receiving procedures should verify the correct product and assess package condition before the material is released for laboratory use.
- Verify SKU: Confirm DWK catalog number 13500-3 against the purchase order.
- Verify material: Confirm the product is identified as solid borosilicate glass beads.
- Verify diameter: Confirm the ordered nominal size is 3 mm.
- Confirm packaging: Check for the one-pound container configuration.
- Inspect the package: Look for damage, leakage of contents, broken glass, or signs of contamination.
- Review documentation: Confirm required lot or material documents have been obtained where applicable.
- Record disposition: Document receiving acceptance or corrective action under the applicable facility procedure.
Receiving checkpoint: Approximately 12,000 beads per pound is a published estimate, not an individually counted unit quantity or a manufacturer-established receiving sampling plan.
Technical FAQs
Are KIMBLE 13500-3 beads solid or hollow?
They are solid borosilicate glass beads, not hollow microspheres or porous polymeric packing.
How many beads are included in a one-pound container?
DWK lists approximately 12,000 beads per pound and approximately 550 beads per cubic inch of bulk packing.
What does the 360 cm³ volume mean?
It is the approximate total bulk volume of beads in the manufacturer's one-pound package. Bulk volume includes the spaces between the packed beads and is not a calibrated liquid capacity.
What is the difference between 13500-3 and 13500-4?
13500-3 is the 3 mm configuration with a ±0.3 mm tolerance. 13500-4 is the 4 mm configuration with a ±0.4 mm tolerance. Both belong to the same solid borosilicate glass bead family.
Can these beads be used with acids?
Borosilicate glass resists many acids, but hydrofluoric acid and hot concentrated phosphoric acid are important exceptions. Confirm compatibility with the exact process.
Are KIMBLE 13500-3 glass beads sterile?
No supplied-sterile designation is established in the reviewed DWK listing. Do not assume sterility, endotoxin control, or certified cleanroom cleanliness.
Can the beads be autoclaved?
Borosilicate glass 3.3 has favorable general thermal properties, but no product-specific validated autoclave cycle was identified. Qualify processing requirements before use.
Do 3 mm beads guarantee better distillation separation than larger beads?
No. Smaller beads change packing surface area and flow characteristics, but separation efficiency depends on the complete column and operating conditions.
Can the beads be reused?
Reuse may be evaluated when compatible cleaning methods, physical inspection, and the laboratory's process requirements permit. No product-specific validated reuse count was identified.
Why purchase KIMBLE laboratory products from SOSCleanroom
- Specialty sourcing: SOSCleanroom supports laboratories and critical environments with technical product identification and purchasing assistance.
- Exact SKU control: Our team can help customers identify the correct manufacturer number, nominal diameter, and package configuration.
- Manufacturer documentation: Customers can request assistance obtaining available product specifications and material documentation.
- Laboratory supply consolidation: Source related laboratory consumables and critical-environment products through SOSCleanroom.
- Responsive customer service: Contact our team for quotations, availability, and manufacturer product information.
Manufacturer documentation and authoritative technical references
- DWK Glass Types & Properties: Review Manufacturer Technical Guide — material classification, thermal expansion, hydrolytic resistance, acid and alkali resistance, and general physical properties.
- Product-specific documentation: Contact SOSCleanroom for assistance requesting available specifications, lot information, or supporting manufacturer records for KIMBLE catalog number 13500-3.
The manufacturer product listing was used to verify bead dimensions, tolerance, material, approximate counts, and packaging. The glass properties guide provides general material science context rather than product-specific certification.
If you have any questions please email us at Sales@SOSsupply.com or give us a call at (214) 340-8574.
For additional product guidance, use the SOSCleanroom AI ChatBot or contact our team for manufacturer documentation assistance.
Technical insight: Bead diameter, borosilicate glass composition, column geometry, and laboratory operating conditions should be evaluated together. Material classification and nominal size do not independently establish process performance.
Last updated: October 28, 2026
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