Calibration solutions that help bring the outer diameter, roundness and surface stability of hot pipe exiting the die head to target dimensions in the vacuum tank.
Product group: Pipe Calibrators (Calibration Sleeves)
Applications: PE • PP • PPR • PERT • PVC • project-based custom
Calibrator types: Fixed / standard • Adjustable • Disc type • Multiplier
Material options: Brass or stainless steel; depending on application and customer request
Correct diameter, stable surface and controlled vacuum.
MILON Endüstri evaluates the calibrator solution according to pipe material, diameter, wall thickness, line speed and vacuum tank conditions. Locally manufactured calibrators can be offered in brass or stainless steel; connection, calibration length, vacuum structure, water channels and other details can be customized to customer request.
What Does a Pipe Calibrator Do?
The hot pipe exiting the die head has not yet reached its final geometric stability. At the entrance of the vacuum tank, the calibrator helps maintain the target outer diameter and roundness by guiding the pipe's outer surface in a controlled manner under contact/vacuum effect.
Extruder → Pipe Head → Calibrator → Vacuum Tank: the head forms the melt flow and pipe cross-section, the calibrator stabilizes the outer diameter and surface.
- Helps keep the pipe outer diameter within target tolerance.
- Helps reduce ovality and diameter fluctuation.
- Supports controlled cooling and shaping of the pipe surface.
- Works together with the vacuum tank to provide continuous line stability.
- Correct surface structure and cooling can help reduce the risk of friction and surface marks.
The calibrator operates after the pipe die head and at the entrance of the vacuum tank.
Calibrator Types
In addition to fixed (standard) and adjustable calibrators, disc-type and multiplier calibrator solutions can also be evaluated depending on the application and line structure.
A fixed calibrator is manufactured with a fixed geometry for a specific pipe outer diameter, while an adjustable calibrator allows limited diameter/tolerance adjustment during production.
Fixed / Standard Calibrator
Designed with a fixed dimension for a specific diameter and product geometry. Considered for series production, standard diameters and situations requiring high repeatability.
Adjustable Calibrator
A structure that allows fine diameter / tolerance adjustment within certain limits. Preferred when precise diameter correction or narrow adjustment is needed during production.
Disc Type Calibrator
Disc-type calibration body; dimensions and structure are determined according to the application. Evaluated on a project basis according to pipe diameter, raw material, line speed and vacuum tank structure.
Multiplier Calibrator
Special multiplier calibration structure; details are verified according to machine and product design. Applied after technical evaluation for non-standard or special process needs.
Real Production Examples
Brass calibrator sets manufactured in different diameters and lengths
Flange-connected calibrator bodies, packaging before shipment
Diameter Ranges
Calibrators are manufactured according to the target pipe outer diameter. The following diameter classes can be used as a reference to give a clear picture of the product group:
- Ø16–63 mm — PPR / PERT / small-diameter PE and technical pipes
- Ø20–110 mm — PPR / PE / PP
- Ø40–160 mm — Medium-diameter pipes
- Ø50–250 mm — PE / PP / PVC applications
- Ø90–400 mm — Large-diameter lines
- Ø110–630 mm — High-capacity large-diameter projects
- Above Ø630 mm — On a project basis according to technical drawing and tank structure
Technical note: Along with the calibrator diameter, calibration length, vacuum channel/hole structure, water channels and tank connection also affect performance. The exact standard and maximum production diameter should be confirmed with our technical team before ordering.
Material Options
Brass or stainless steel calibrator solutions can be offered depending on the application and customer request.
- Brass — Good heat transfer, machinability and common use in many pipe applications.
- Stainless Steel — Can provide advantages in corrosion resistance, surface durability and longer service life depending on the application.
Selection note: Material should not be chosen on its own; pipe raw material, line speed, cooling conditions, vacuum level and target surface quality should be evaluated together.
Custom Manufacturing
The following parameters are customized to your needs on a project basis:
- Calibrator outer and inner geometry
- Total calibration length
- Vacuum holes / channels and their distribution
- Water cooling channels
- Tank inlet connection and flange dimensions
- Connection details for easy assembly/disassembly
- Brass or stainless steel material selection
- Reverse engineering based on an existing calibrator
Local Manufacturing and Supply Approach
Locally manufactured calibrators offer a strong option, especially for single or low-quantity needs, projects requiring fast lead times, and custom sizing adjustments on an existing line. Since technical revisions and dimension confirmation can be carried out directly, the project process can proceed in a more controlled way.
When order quantity, project schedule and technical requirements are suitable, international supply can also be considered. The decision is made taking into account freight, taxes, lead time, revision possibilities and overall project conditions in addition to the product price.
Information Needed to Determine the Right Calibrator
- Pipe material
- Pipe outer diameter and tolerances
- Wall thickness / SDR / PN information
- Target line speed
- Vacuum tank brand/model or inlet dimensions
- Existing calibrator technical drawing, dimensions or sample
- Current calibration length and connection details
- Preferred material: brass / stainless steel
- Problem experienced: ovality, surface marks, diameter deviation, friction, insufficient cooling, etc.
Frequently Asked Questions
Does the calibrator determine the number of layers?
No. The 2-, 3- or 5-layer pipe structure is formed at the die head. The calibrator is concerned with the pipe's outer diameter and geometric stability.
Can a new calibrator be manufactured based on an existing one?
Yes. New production can be evaluated by measuring the existing part or based on a reliable technical drawing. The tank connection and process conditions should also be checked.
Is brass or stainless steel better?
There is no single correct answer. The material should be selected based on the pipe raw material, line speed, cooling, vacuum, surface expectations and service conditions.
Is changing only the calibrator enough for a new diameter?
Compatibility of the die head, vacuum tank, puller and other line equipment with the new diameter must be checked together.
