TSR 10/20 production normally includes feedstock acceptance and preparation, wet-line breaking and washing, blending, multi-stage kneading, creping and granulation, wet-crumb conveying and trolley filling, drying and cooling, weighing and baling, inspection, packaging and finished-product storage. The required number of stages and machines depends on feedstock, product specification, target output, energy supply and plant conditions.
What is TSR 10/20?
TSR means technically specified rubber. TSR 10 and TSR 20 are common grades in natural rubber processing. The final quality requirements must be defined by the product standard applicable in the destination market, the customer specification and the agreed test methods.
Projects in China may apply GB/T 8081-2018; international trade may refer to ISO 2000:2020. TSR packaging, marking, storage and transport may apply GB/T 8082-2018. ISO 2000 provides guidance for parties to agree TSR requirements; it does not replace a project contract or customer specification.
A project quality plan should identify the destination market, applicable standards, additional customer limits, sampling method and test methods rather than treat one country's TSR 10/20 limits as universal.
The process described here mainly concerns cup lump, field coagulum, coagulated sheets and other approved coagulated feedstocks. Moisture, contamination, hardness, storage history and batch consistency can vary significantly, so a production line should not be selected from one fixed flow sheet or one fixed parameter set.
1. Feedstock acceptance and preparation
Before feedstock enters the line, it is normally weighed, visually inspected, sampled and classified. The review may include feedstock type and origin, dry-rubber or moisture condition, mud, bark, metal and other foreign matter, storage-related hardening or deterioration, and variation between lots.
Acceptance data supports later blending, soaking, breaking and quality control. Large or hard lumps may need cutting, spraying or soaking to soften them and stabilize continuous feeding. Preparation time and method should change with feedstock condition.
2. Breaking, washing and blending
Prepared rubber normally passes through breaking equipment that progressively reduces the size of large lumps. Washing tanks, conveyors and rubber-handling devices then wash and transfer the material.
This stage has three main functions:
- reduce irregular or hardened lumps to a form that downstream machines can process consistently;
- separate mud, sand and other removable contamination; and
- progressively blend feedstocks of different origins and conditions to reduce batch variation.
A production line may use several breaking, washing and blending stages. The required number should be based on feedstock trials and production objectives. More complex and less uniform feedstock usually requires more attention to staged processing and blending.
Washing performance is not determined by water consumption alone. Lump size, soaking, tank design, drainage and sludge removal, feeding uniformity and recycled-water management also affect contamination removal and continuity.
3. Kneading, creping and granulation
After initial breaking and washing, rubber may pass through wet mixing or screw kneading, creping and shredding or granulation.
- Wet mixing or screw kneading: applies compression and shear, further works the material and removes part of the free water.
- Creping: passes rubber between rollers to form a continuous or near-continuous crepe and improve blending.
- Shredding or granulation: divides crepe into wet crumb suitable for conveying, trolley filling and drying.
Multiple stages are not added simply to increase machine count. Their purpose is to progressively improve consistency, dewatering and crumb form. Oversized or agglomerated crumb can impair filling and drying, while unsuitable rubber hardness or discontinuous feeding can cause crepe breakage, blockage and capacity fluctuation.
Roll gap, speed, feed rate, water, rubber hardness and machine-to-machine transfer must therefore be coordinated as one system.
4. Wet-crumb conveying and trolley filling
Wet crumb can be transferred to the filling station by conveyor, crumb pump or another method suited to the project. The filling station separates crumb from transfer water and distributes it into drying trolleys.
Crumb distribution, loading quantity and bed density should be consistent across each trolley. Local overloading, dense agglomeration or stuck-together crumb can obstruct heat and airflow; underloading reduces trolley utilization. Any special process treatment must follow the product requirement and an approved project-specific technical plan.
5. Drying, cooling and unloading
Loaded trolleys enter the dryer at the engineered interval. Controlled heat and airflow remove moisture from the wet crumb. Depending on local energy conditions, the dryer may use diesel, natural gas, steam, thermal oil or hot air.
Drying control must consider feedstock moisture and crumb form, loading quantity and distribution, heat-supply temperature and stability, air volume, pressure and distribution, drying time and trolley interval, and cooling time and rubber condition after discharge.
Temperature is not the only factor. Raising it cannot replace uniform granulation, loading or airflow and may increase the risk of surface overheating, tackiness or insufficient internal drying. Time, temperature and trolley interval should be confirmed through feedstock condition, equipment design, commissioning results and product testing.
After discharge, rubber is cooled before unloading, weighing and baling. An automatic project may use a bale-unloading robot, while a conventional line may use manual or mechanically assisted unloading.
6. Weighing, baling and packaging
Cooled rubber is weighed and adjusted before it is compressed to the specified bale form. Where needed, a rubber cutter or other weight-adjustment equipment can be used.
A conventional packaging section may include weighing, weight adjustment, baling, check weighing, film or bag packaging, metal inspection and conveying. An automatic line can add automatic unloading, feeding, internal bale inspection, turning, film wrapping, bagging, robotic palletizing or box loading.
Conventional and automatic packaging use the same fundamental quality logic: bale weight, form, internal condition, packaging integrity and metal inspection must meet the project requirement. The main difference is whether handling, inspection and packaging actions are manual, mechanically assisted or automated.
7. Product testing and storage
Production requires a sampling and testing system aligned with the target product. Feedstock tests, process checks and finished-product tests should be connected so that changes in feedstock and operation can be traced to product quality.
Chinese test methods include GB/T 8086-2019 for dirt content, GB/T 3510-2023 for rapid plasticity, GB/T 3517-2022 for plasticity retention index, GB/T 8088-2025 for nitrogen and GB/T 15340-2025 for sampling and sample preparation. Laboratory records and reports should state the complete standard number and edition used.
After the rubber meets the applicable standard and customer specification, it is marked, batch-recorded, packaging-checked and stored. If a test result is abnormal, the investigation should connect the feedstock lot, wet-line operation, crumb form, drying record and packaging process.
Why line configuration is project-specific
TSR 10/20 factories can differ in feedstock condition, line count, trolley loading, heat-supply system, plant layout and automation scope. Process stages, machine models, capacity matching and operating parameters should therefore be defined from feedstock trials, product requirements and site conditions rather than copied from one fixed flow sheet.
Sinyoung's project cases also show why the same label does not mean the same configuration. Mainland Group Plants 3, 4 and 5 in Côte d'Ivoire and KIMS Rubber in Cambodia use different trolley intervals and equipment combinations. A capacity achieved in one project cannot be transferred to another without considering trolley loading, feedstock and equipment conditions.
Frequently asked questions
Must TSR 10 and TSR 20 use exactly the same line?
No. They can share many processes and machines, but feedstock, target limits, blending, number of stages and process control may differ. Project design should be based on feedstock tests, product requirements and operating conditions.
Are more breaking, creping and granulation stages always better?
No. Each stage should serve contamination removal, blending, dewatering, crumb formation or stable feeding. Too few stages may not achieve the process objective, while unnecessary stages increase investment, energy, maintenance and coordination requirements.
Is rated capacity the same as stable operating capacity?
No. Design capacity, theoretical conversion, a single operating observation and stable production capacity are different concepts. Feedstock, loading, drying time, equipment coordination, maintenance and product quality all affect actual output.
Can output be increased simply by raising drying temperature?
No. Output depends on wet processing, crumb form, trolley loading, heat supply, airflow, drying time and product quality. Excessive or unstable temperature can increase quality risk.
Technical reference: Introduction to Natural Rubber Primary Processing Technology, 2009, Chapter 4, Sections 1–2.