The CXXK Series Two Roll Open Mixing Mill is an industrial rubber processing machine designed for rubber mixing, hot refining, sheeting, plasticizing, and compound preparation.
Featuring two counter-rotating rolls and a single-output-shaft reducer drive system, this machine provides controlled mechanical shearing and friction between the rolls to help disperse fillers, blend additives, and achieve uniform rubber compounds.
Available in 13 model configurations from CXXK-250 to CXXK-810, the series offers different roll diameters, working lengths, motor powers, and batch capacities to meet the requirements of rubber processing plants, industrial manufacturers, and formulation development facilities.
Chenxing Machinery provides flexible configuration options, including manual, electric, and hydraulic roll-gap adjustment, as well as fixed-speed and variable-frequency speed control.
A Two Roll Open Mixing Mill, also known as a Two Roll Rubber Mixing Mill or Open Rubber Mixing Mill, is a mechanical processing machine used to mix, refine, plasticize, and sheet rubber materials.
The machine consists of two horizontally arranged rolls that rotate in opposite directions. Different roll surface speeds create a friction ratio, generating shear forces that help distribute fillers, plasticizers, curing agents, and other additives throughout the rubber compound.
During operation, rubber material is continuously fed into the space between the two rolls. Through repeated rolling, shearing, folding, and feeding, the material gradually becomes more uniform.
The CXXK Series is primarily designed for rubber processing applications, including:
Rubber compounding and mixing
Natural rubber and synthetic rubber processing
Rubber plasticizing
Rubber hot refining
Rubber sheeting
Rubber formulation development
Industrial rubber material preparation
Typical downstream applications include rubber sheets, rubber mats, seals, gaskets, hoses, profiles, footwear materials, and molded rubber products.
The final processing results depend on the rubber formulation, operating conditions, roll temperature, friction ratio, and processing time.
The CXXK Series adopts a single-motor drive system with a single-output-shaft reducer and gear transmission.
The motor provides the driving power, which is transmitted through the reducer and gear system to operate the two mixing rolls at different rotational speeds.
The two rolls rotate in opposite directions, creating a friction ratio between the front and rear rolls.
This speed difference generates shear forces that help mix and refine rubber materials.
Step 1: Material Feeding
Raw rubber and other formulation ingredients are introduced into the space between the two rolls.
Step 2: Rolling and Shearing
The rotating rolls pull the material into the roll gap. The difference in surface speeds generates friction and mechanical shear.
Step 3: Ingredient Dispersion
Repeated rolling and folding help distribute fillers, oils, and other additives throughout the rubber compound.
Step 4: Roll Gap Adjustment
Operators can adjust the distance between the rolls according to material characteristics and processing requirements.
Step 5: Rubber Sheeting
The processed rubber is gradually formed into sheets for storage, transportation, or subsequent manufacturing operations.
The machine uses a single motor connected to a single-output-shaft reducer, with gear transmission for roll operation.
This mechanical arrangement provides a centralized drive configuration for the two-roll mixing system.
The rolls are manufactured from chilled cast iron and feature hard chromium-plated surfaces.
Two roll structures are available:
Hollow rolls
Drilled rolls
Different roll structures can be selected according to the required heating or cooling arrangement and processing conditions.
The CXXK Series offers three roll-gap adjustment configurations:
Manual roll-gap adjustment
Electric roll-gap adjustment
Hydraulic roll-gap adjustment
Customers can select the appropriate adjustment system according to machine size and production requirements.
The roll rotational speed can be configured with either fixed-speed operation or variable-frequency speed control.
Variable-frequency control allows operators to adjust roll speed according to different processing requirements.
The roll friction ratio is an important operating parameter in rubber mixing.
Different CXXK models feature friction ratios ranging from 1:1.09 to 1:1.27 in the listed specifications.
The speed difference between the two rolls contributes to the mechanical shear required for rubber compounding and refining.
The machine can be equipped with multiple safety devices, including:
Emergency stop buttons
Knee-operated safety switches
Pull-cord safety switches
These devices provide emergency stopping functions to help protect operators during machine operation.
Depending on the production process, the machine can be equipped with suitable feeding equipment according to material characteristics and production requirements.
The Chenxing CXXK Series is available in 13 model configurations, covering roll diameters from 250 mm to 810 mm.
| Technical Parameter | Specification |
|---|---|
| Product Type | Two Roll Open Mixing Mill |
| Series | CXXK Series |
| Drive System | Single motor, single-output-shaft reducer |
| Transmission | Gear transmission |
| Roll Material | Chilled cast iron |
| Roll Surface | Hard chromium plated |
| Roll Structure | Hollow or drilled |
| Roll Gap Adjustment | Manual / Electric / Hydraulic |
| Speed Control | Fixed speed / Variable frequency |
| Roll Diameter Range | 250–810 mm |
| Roll Working Length | 620–2540 mm |
| Batch Capacity | 10–350 kg |
| Motor Power | 18.5–355 kW |
| Technical Parameter | CXXK-250 | CXXK-300 | CXXK-360 | CXXK-400 | CXXK-450 | CXXK-550 | CXXK-560 | CXXK-610 | CXXKY-660 | CXXKR-660 | CXXK-710 | CXXK-760 | CXXK-810 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Roll Diameter (mm) | 250 | 300 | 360 | 400 | 450 | 550 | 560 | 610 | 660 | 660 | 710 | 760 | 810 |
| Roll Working Length (mm) | 620 | 760 | 900 | 1000 | 1200 | 1530 | 1530 | 1830 | 2130 | 2130 | 2200 | 2540 | 2540 |
| Front Roll Linear Speed (m/min) | 15.2 | 14.5 | 16.26 | 18.65 | 23.85 | 27.18 | 27.61 | 28.7 | 32.45 | 28.6 | 31.9 | 33.23 | 31.9 |
| Roll Friction Ratio | 1:1.10 | 1:1.10 | 1:1.25 | 1:1.27 | 1:1.27 | 1:1.25 | 1:1.25 | 1:1.25 | 1:1.09 | 1:1.24 | 1:1.09 | 1:1.09 | 1:1.09 |
| Batch Capacity (kg) | 10–15 | 14–16 | 15–20 | 25–35 | 30–50 | 50–60 | 50–60 | 90–120 | 165 | 165 | 350 | 350 | 350 |
| Motor Power (kW) | 18.5 | 22 | 30 | 40 | 55 | 110 | 110 | 160 | 185 | 250 | 280 | 315 | 355 |
| Maximum Nip (mm) | 8 | 8 | 10 | 10 | 10 | 15 | 15 | 15 | 15 | 15 | 15 | 15 | 15 |
| Weight (t) | 3.8 | 4.5 | 6 | 8 | 13 | 22 | 22 | 35 | 45 | 45 | 50 | 58 | 68 |
| Model | Length (mm) | Width (mm) | Height (mm) |
|---|---|---|---|
| CXXK-250 | 3220 | 1500 | 1290 |
| CXXK-300 | 3570 | 1400 | 1350 |
| CXXK-360 | 3920 | 1650 | 1725 |
| CXXK-400 | 4380 | 1710 | 1880 |
| CXXK-450 | 5050 | 1920 | 1870 |
| CXXK-550 | 6040 | 2100 | 1625 |
| CXXK-560 | 6040 | 2100 | 1625 |
| CXXK-610 | 6750 | 3040 | 1743 |
| CXXKY-660 | 7040 | 3620 | 2080 |
| CXXKR-660 | 7465 | 3660 | 2080 |
| CXXK-710 | 7650 | 3200 | 2860 |
| CXXK-760 | 8560 | 2970 | 1970 |
| CXXK-810 | 8680 | 3575 | 3020 |
Note: Specifications are based on the supplied product data. Actual machine dimensions, batch capacity, and optional equipment should be confirmed with Chenxing Machinery before ordering.
Selecting an appropriate open mixing mill requires more than comparing roll diameters or motor power.
The machine should match the customer's material formulation, batch size, processing requirements, and downstream production equipment.
Batch capacity is one of the most important factors when selecting a model.
For example:
CXXK-250: 10–15 kg per batch
CXXK-400: 25–35 kg per batch
CXXK-450: 30–50 kg per batch
CXXK-550: 50–60 kg per batch
CXXK-610: 90–120 kg per batch
CXXKY-660 / CXXKR-660: 165 kg per batch
CXXK-710 and larger models: up to 350 kg per batch
Actual capacity depends on the material and processing conditions.
Roll diameter and working length affect the available working area and the machine's processing capacity.
The appropriate model should be selected according to batch size, rubber formulation, and production cycle.
Manual adjustment is a practical option for certain smaller or less frequently adjusted applications.
Electric and hydraulic adjustment systems can be considered when more convenient roll-gap adjustment is required.
Fixed-speed operation may be suitable for production processes with relatively consistent operating conditions.
Variable-frequency control provides greater flexibility when different formulations require different roll speeds.
An open mixing mill may operate independently or as part of a complete rubber processing system.
The feeding method, material handling process, cooling arrangements, and downstream equipment should be considered before confirming the machine configuration.
The CXXK Series supports different configuration choices to match specific operating conditions.
Roll Gap Adjustment
Manual adjustment
Electric adjustment
Hydraulic adjustment
Speed Control
Fixed-speed configuration
Variable-frequency speed control
Roll Structure
Hollow rolls
Drilled rolls
Feeding System
Optional feeding equipment according to the production process
Safety Protection
Emergency stop button
Knee-operated safety switch
Pull-cord safety switch
The final configuration can be discussed based on the customer's material type, production capacity, and operating requirements.
Chenxing Machinery is a Chinese manufacturer specializing in plastic extrusion machinery, plastic recycling equipment, mixing systems, and related industrial machinery.
Our approach is to understand the actual application before recommending a machine configuration.
We focus on:
Model Selection: Multiple roll diameters and working lengths for different batch capacities.
Configuration Flexibility: Different roll-gap adjustment and speed-control options.
Application-Based Solutions: Machine configuration according to material characteristics and production requirements.
Manufacturing and Assembly: Equipment manufacturing and assembly with attention to mechanical structure and operating requirements.
Technical Communication: Assistance with machine specifications, optional equipment, and application requirements before ordering.
Our objective is to provide practical equipment solutions that match the customer's actual production process.
A Two Roll Open Mixing Mill is primarily used for rubber mixing, hot refining, plasticizing, and sheeting. It helps blend raw rubber with fillers, oils, and other formulation ingredients through mechanical rolling and shearing.
An open mixing mill processes materials between two exposed rolls, allowing operators to observe and manually handle the material during processing.
An internal mixer processes materials inside an enclosed mixing chamber using internal rotors.
Open mixing mills are often used for batch mixing, refining, sheeting, and formulation adjustments, while internal mixers are commonly used for enclosed, intensive mixing operations.
The friction ratio refers to the ratio between the surface speeds of the two rolls.
For example, a friction ratio of 1:1.25 means that one roll has a surface speed 25% higher than the other.
This speed difference generates shear forces that contribute to the mixing and refining of rubber compounds.
Manual adjustment requires operators to adjust the roll gap mechanically.
Electric adjustment uses an electric drive mechanism to change the roll gap.
Hydraulic adjustment uses hydraulic force to control the roll position.
The appropriate option depends on machine specifications and production requirements.
Yes. The CXXK Series is designed for rubber processing applications, including natural rubber and various synthetic rubber compounds.
The final machine configuration should be selected according to the specific rubber formulation and processing conditions.
The current CXXK Series specifications cover batch capacities from 10 kg to 350 kg, depending on the model.
Yes. The machine can be configured with fixed-speed operation or variable-frequency speed control.
Yes. Different roll-gap adjustment systems, speed-control configurations, roll structures, feeding devices, and safety protection options can be discussed according to the customer's requirements.
To recommend a suitable model, please provide:
Material type and rubber formulation
Required batch capacity (kg per batch)
Required roll diameter or working length, if known
Preferred roll-gap adjustment method
Fixed-speed or variable-frequency control requirements
Available factory installation space
Destination country
These details help us evaluate the appropriate model and machine configuration.
Looking for a reliable two roll open mixing mill for your rubber processing plant?
Chenxing Machinery offers multiple CXXK Series configurations to meet different batch capacities and processing requirements.
Whether you need a compact rubber mixing mill for small-batch production or a large industrial two roll mill for higher-capacity applications, our team can help you evaluate the appropriate machine specifications.
Send us your material type, required batch capacity, and processing requirements.
Our team will help you identify a suitable CXXK Series model and discuss the available configuration options.
Contact Chenxing Machinery for a customized quotation and technical solution.
Chenxing Machinery is a Chinese industrial machinery manufacturer specializing in plastic extrusion equipment, plastic recycling systems, industrial mixing machinery, and automatic dosing systems.
The CXXK Series Two Roll Open Mixing Mill is designed for rubber mixing, refining, plasticizing, and sheeting applications. Multiple models are available with roll diameters ranging from 250 mm to 810 mm, batch capacities from 10 kg to 350 kg, and motor power ratings from 18.5 kW to 355 kW.
Machine configurations can be selected according to material characteristics, production capacity, roll-gap adjustment requirements, and speed-control preferences.