Prestolok push-in reducing union — splices two different tube diameters
TECTUL · Dispatch across Colombia · Exports to Central & South America
Push-in reducing union: each end accepts a different tube diameter, to directly splice two sections of different sizes without installing two separate reducing fittings. PBT body with a nickel-plated brass collet at each end. The manufacturer documents 8 imperial combinations with verified length and weight, and 8 metric combinations with verified length.
IMPORTANT: reference data — may differ from the physical product; verify with an advisor before buying.
SKU VT-RAC-UNIONREDPRESTO (push-in reducing union) · 16 combinations · sold by the unit
1. Technical specifications
Imperial combinations
| Diameter 1 x Diameter 2 | L [mm] | Weight [g] |
|---|---|---|
| 1/4″ x 1/8″ | 42.00 | 16 |
| 5/16″ x 1/8″ | 38.50 | 6 |
| 5/16″ x 1/4″ | 38.00 | 9 |
| 3/8″ x 1/8″ | 42.00 | 10 |
| 3/8″ x 1/4″ | 42.00 | 11 |
| 3/8″ x 1/2″ | 49.00 | 7 |
| 1/2″ x 1/4″ | 41.60 | 13 |
| 1/2″ x 3/8″ | 48.50 | 14 |
IMPORTANT
This technical data sheet is a reference guide to the properties of this product type; it is not a quality certificate for the product you are buying. The measurements, dimensions and physical or geometric characteristics of the product supplied may vary by manufacturer, heat and lot, and may even fall outside the cited standards. If any of these figures is critical to your design or build, verify it with one of our advisors against the physical product or the lot's mill certificate, so you can be fully certain of what you are buying. · Original data sheet: tectul.com/en/conduccion-de-fluidos/racores-y-acoples/ficha-tecnica-union-reducida-prestolok.html
Metric combinations
| Diameter 1 x Diameter 2 | L [mm] | Weight [g] |
|---|---|---|
| 6mm x 4mm | 35.00 | Confirmed on quotation |
| 8mm x 4mm | 38.00 | Confirmed on quotation |
| 8mm x 6mm | 36.00 | Confirmed on quotation |
| 10mm x 6mm | 42.00 | Confirmed on quotation |
| 10mm x 8mm | 43.40 | Confirmed on quotation |
| 12mm x 10mm | 45.00 | Confirmed on quotation |
| 12mm x 6mm | 45.00 | Confirmed on quotation |
| 12mm x 8mm | 47.40 | Confirmed on quotation |
IMPORTANT: reference data — may differ from the physical product; verify with an advisor before buying.
Manufacturer tables (May 2022 revision). In the metric combinations, weight appears in the source table in a column that does not align unambiguously with each combination; to avoid attributing a value to the wrong row, it is declared "confirmed on quotation" rather than assigned by position.
| Product | Push-in union with a different diameter on each end |
| Material | PBT body · nickel-plated brass collet at each end |
2. Frequently asked questions
Can I splice 3/8″ with 10 mm using this part?
No; each combination of this reducing union is defined within the same measurement system (imperial with imperial, metric with metric). To cross systems, check with the supplier whether a mixed reference exists.
Why does the metric combinations' weight say "confirmed on quotation"?
The manufacturer's source table does not align weight with each metric combination unambiguously; rather than assign it by guesswork, it is left pending confirmation.
3. Application notes
Feasibility
Suitable for splicing two pneumatic tube sections of different diameter within the same measurement system (imperial or metric).
Installation
Cut each tube section square and burr-free; insert fully to the stop at the end of the matching diameter and verify by gently pulling.
Design
Confirm the exact weight of metric combinations with the supplier before calculating support loads. Verify both sections to be spliced use the same measurement system.
4. Technical notice and limitation of liability
The pressures, dimensions, weights and other characteristics in this sheet are theoretical calculation values obtained from nominal properties published in the standards cited (ASME B36.10-2022, ASME B31.3-2024, ASTM A106/A106M-19a, ASTM A53/A53M-24, API Spec 5L 46th ed.). They guide selection; they are not a certificate of conformity for any given lot.
The actual behavior of each lot varies with manufacturing — wall tolerance (up to −12.5%), out-of-roundness, residual stresses — and with the raw material — chemical composition within the ranges the standard allows, heat-to-heat differences. To certify a lot, the tests defined by its product standard are required: tensile test, flattening test and hydrostatic test, documented in the manufacturer's mill test certificate (MTC), which TECTUL supplies upon request; testing of the lot in an independent laboratory can also be arranged.
These values must not be used as the sole criterion in critical or safety applications, or wherever failure of the line may compromise people, property or the environment: in such cases the design belongs to the project's responsible engineer under the applicable code (ASME B31.3, B31.1 or the one governing the installation), with the design temperature, corrosion allowance and load cases of the actual service. Before deciding with these data, consult our technical team.
Sources
- Ficha de fabricante "Unión Reducida Prestolok" (catálogo de racores push-in neumáticos, IMR/TECTUL, revisión mayo 2022): 8 combinaciones imperiales con L y peso; 8 combinaciones métricas con L
This data sheet is the property of TECTUL, part of the Industrias IMR group. Reproduction without attribution is prohibited. Original document and updates: tectul.com/en/conduccion-de-fluidos/racores-y-acoples/ficha-tecnica-union-reducida-prestolok.