End-to-end solutions from raw materials to production equipments for PU foam and mattress-Sabtech
What Is Mattress Tape Edge Sewing Machine?
The design of mattress tape edge sewing machine can be described as what we call timeless. It is elaborately designed and has an aesthetic streak. There is a timeless quality to the product' performance and it works with strong stability and dependability. Sabtech Technology Limited has proved to all that the product has met the strictest quality standard and is extremely safe for people to use.
Sabtech attaches great importance to the experience of products. The design of all these products is carefully examined and considered from the perspective of users. These products are widely praised and trusted by customers, gradually showing its strength in the international market. They have received market reputation due to acceptable prices, competitive quality and profit margins. Customer evaluation and praise are the affirmation of these products.
Frequently the after-sales service is the key to brand loyalty. Except for offering products with high cost-performance ratio at Sabtech Technology Limited, we focus attention on improving customer service. We hired experienced and highly educated staff and built an after-sales team. We lay out agendas to train workers, and conduct practical role play activities between co-workers so that the team can acquire proficiency in both theoretical knowledge and practical exercise in serving customers.
From a Continuous Foaming Line Inquiry to an Integrated Foam Production Setup
Project Background
In September 2021, we received an inquiry from Mr Abdullah, a client from Saudi Arabia. He planned to build a new PU foam factory serving the Saudi local market and the Yemeni market, mainly for furniture and mattress flexible PU foam products. He also planned to include downstream processing.
The client had local foaming workers and some basic production conditions in place. As the project moved forward, it required coordinated planning of target products, equipment configuration, factory layout, and the connection between foaming and downstream processing.
How the Project Scope Expanded
The client’s initial inquiry focused on a continuous foaming line. As the discussions progressed, the project scope expanded to include rebonded foam production and the cutting equipment required for downstream processing.
One important consideration was how the factory would handle foam offcuts after production increased. The local market for rebonded foam was relatively strong, while the local selling price for baled foam offcuts was low. As the planned production scale increased, the factory was expected to generate foam offcuts regularly. Processing this material into rebonded foam would provide greater long-term value than selling it directly as low-value scrap.
The client therefore decided to add a complete rebonded foam production line. From a longer-term production and market perspective, combining the continuous foaming line with rebonded foam production was better suited to the planned scale of the factory.
The project also included the required downstream cutting equipment. The CNC foam cutting machine was selected for shaped foam parts used in furniture and mattress products. Two circular foam cutting machines allowed multiple foam blocks to be sliced within the same cutting cycle, while the vertical foam cutting machine was mainly used for trimming block edges and carrying out straight cuts before further processing.
Based on the factory conditions, we also prepared a layout covering equipment placement, production flow, the connection between foaming and downstream processing, and operator working space. Through several video meetings, the client observed an actual flexible foam production process, including the operation of the continuous foaming line and its connection with downstream cutting and processing. The discussions also covered daily operation, practical differences between equipment designs, and the configurations suitable for this project.
The rebonded foam machine purchased by this client
Why the Client Finally Chose Us
The client compared proposals from several equipment suppliers before making the final decision. What distinguished Sabtech was not simply the ability to supply the required machines, but the client’s greater confidence in our communication, understanding of the project, and approach to developing the solution.
1. Responsive Communication with Clear Follow-Through
As the project developed, the client’s questions were answered promptly and directly. Details confirmed during earlier discussions were carried forward into the subsequent planning, allowing the project to progress from the initial inquiry to the final equipment plan without repeatedly revisiting the same issues.
2. Project-Specific Planning Rather Than a Standard Package
The proposed solution was developed around the client’s target products, factory conditions, existing foaming workers, and downstream processing requirements. The equipment plan and factory layout were connected to how the factory was expected to operate, rather than being presented as a standard equipment package.
3. Recommendations Grounded in Actual Foam Production
During several video meetings, the client observed an actual flexible foam production process and discussed daily operation, practical differences between equipment designs, and configuration choices.
After comparing the suppliers, the client had greater confidence in Sabtech’s overall understanding of the project and selected us for the complete equipment order.
Final Procurement Content
- one complete continuous foaming production line for producing virgin flexible PU foam used in furniture and mattress applications
- one rebonded foam production line, including: rebonded foam machine, steam boiler, foam shredder machine for rebonded foam production
- one CNC foam cutting machine for cutting shaped foam parts required by furniture and mattress products
- two circular foam cutting machines for slicing multiple foam blocks in the same cutting cycle to reduce processing time
- one vertical foam cutting machine for trimming foam block edges and carrying out straight cuts before further processing
Loading rebonded foam line
Loading continuous foam machine and foam cutting machine
Remote Installation and Production Startup
The equipment arrived at the client’s factory in July 2022. Because pandemic-related travel restrictions prevented our engineer from travelling to the site, installation and commissioning support were provided remotely. Commissioning was completed in October, and production started in November 2022.
After the initial setup entered production, the client later placed two additional orders to expand the factory’s downstream processing capacity and product applications. The subsequent development of the factory is covered in How a Saudi PU Foam Factory Expanded Beyond Its Initial Production Lines.
Project Background And Customer Needs
This Malaysian mattress manufacturer previously purchased foam for processing into mattresses and wanted to expand upstream into foam production. Rebonded foam was a practical starting point: the factory already used it in its mattresses, there was demand in the local market, and the production process presented a relatively accessible entry point for the customer.
The initial plan was to supply its own mattress production, with external sales to follow once production was established and capacity expanded. As a newcomer to rebonded foam manufacturing, the customer needed guidance on equipment configuration, raw material preparation, and the production process.
Early Communication And Solution Confirmation
We first discussed the target density and firmness, the customer's mattress applications, and local market requirements. As a first-time producer, the customer had many basic questions and was particularly concerned about whether it could produce foam of the expected quality after purchasing the equipment.
We responded promptly and provided practical explanations of equipment selection, raw material preparation, and production methods, together with the support available during startup. These responses and the proposed support helped build the customer's confidence in Sabtech.
The customer then visited our factory for an on-site evaluation. During the visit, we arranged for the customer to review the actual rebonded foam production process, equipment operating conditions, and different layout approaches under factory conditions. In addition to checking the machine itself, the customer also reviewed several practical issues related to project start-up, including:
- factory space arrangement
- initial investment differences
- workflow connection
- future production expansion
The configuration comparison focused on whether to include steam curing and how many mold boxes to use. These choices were evaluated against the target daily output, production efficiency, and available factory space.
Steam curing shortens the time required before demolding, allowing the mold boxes to return to use sooner. This reduces the number of additional mold boxes needed to maintain the production schedule.
The customer selected a rebonded foam machine with steam curing and two mold boxes, allowing two blocks to be produced in one cycle. This configuration matched its target daily output and available factory space.
Installation, Training, And Project Start-Up
After installation, our engineers trained the customer's team in machine operation and the production process, covering:
- Raw material preparation
- Coordination between production steps
- Operating sequence
- Practical operating precautions
After installation and training were completed, the customer successfully entered trial production and produced the rebonded foam product required for the project.
Follow-Up Cooperation
Once rebonded foam production was running steadily, the customer decided to add virgin foam production capability and purchased a semi-automatic batch foam machine from Sabtech. The customer also continued to reorder foam chemicals from us.
If you are evaluating a rebonded foam project, you are welcome to discuss machine configuration, factory layout, and start-up planning with us.
For many small-scale enterprises, although the continuous production line of polyurethane flexible foam offers high output, the costs are also very high, and the target market may not require such large quantities. As a result, non-continuous production lines for polyurethane flexible foam have become their preferable choice. The following is an introduction to the non-continuous production line for polyurethane flexible foam:
1. Box Foaming Process Equipment
The box foaming process and equipment have been developed as a new technology to accommodate the needs of small-scale polyurethane foam production facilities. It builds upon laboratory and manual foam production techniques, essentially an upscaled version of laboratory foam methods. This process has gone through three development stages. Initially, all component materials were sequentially weighed and added to a larger container, followed by the addition of TDI. After rapid mixing, the mixture was immediately poured into a large box mold. This method had high labor intensity, emitted high concentrations of toxic gases, and posed significant health risks to operators. Additionally, the splattering of materials during pouring would entrain a large amount of air, leading to the formation of large air bubbles within the foam structure and even causing foam cracking. Furthermore, there was a significant amount of leftover waste, resulting in substantial material waste and high production costs.
Later on, the process incorporated metering pumps to convey materials to a mixing barrel with an automatically opening bottom. After high-speed mixing, the bottom plate of the mixing barrel would open, and compressed air would swiftly expel the material into the mold for foam expansion. However, this approach suffered from uneven foam pore structures due to the rapid material flow, leading to swirling foam structures and quality issues like crescent-shaped cracks. The third stage of process improvement is the box foaming device that is mostly adopted today. Its fundamental foaming principle is illustrated in Picture
(a) Raw Material Metering and Mixing (b) Foaming (c) Foam Rises to Limit Height
1 - Elevatable Material Mixing Barrel; 2 - Assemblable Box Mold; 3 - Floating Box Top Plate; 4 - Foam Body
Picture 1: Schematic Diagram of Box Foaming Principle
The industrial production equipment for box foaming primarily consists of raw material tanks, metering pump units, elevatable mixing barrels, and assemblable wooden box molds. As depicted in the schematic diagram of the box foaming equipment manufactured by Hennecke (Picture 2), the foaming raw materials are stored in tanks and regulated by control devices to attain the required processing temperature range, typically maintained at 23°C ± 3°C. Sequentially, the metering pump injects polyether polyols, catalyst, surfactants, foaming agents, etc., into the mixing barrel for a stirring duration of 30 to 60 minutes. Next, according to the formulation, TDI is introduced, either directly or through an intermediate container with a bottom switch. Immediate mixing follows TDI addition. Depending on the materials and formulation, the stirring speed is usually controlled at 900 to 1000 revolutions per minute (r/min), with a stirring time of 3 to 8 seconds. After stirring, the mixing barrel is swiftly lifted. The lower part of the barrel lacks a bottom and is placed on the mold box's bottom plate upon lowering, utilizing a sealing ring at the barrel's bottom edge to prevent material leakage.
When lifted, the well-mixed slurry can be directly spread and dispersed on the bottom plate of the box mold, allowing natural foam rise. To prevent the formation of a domed surface on the upper part during foaming, an upper mold plate that matches the mold area and allows for upward limit movement is equipped. The mold box primarily comprises rigid wooden panels, with the bottom plate fixed on a movable mold transport carriage. All four side panels are assemblable, featuring quick-opening and closing locking mechanisms. The inner sides of the panels are coated with silicone-based release agents or lined with polyethylene film material to prevent adhesion. After 8 to 10 minutes of forced maturation within the box, the side panels of the mold box are opened, allowing the removal of block-shaped flexible foam. Following an additional 24 hours of maturation, these foam blocks can undergo cutting and other post-processing procedures.
1 - Raw Material Tank; 2 - Metering Pump Unit; 3 - Control Cabinet; 4 - Mixing Barrel with Elevating Device; 5 - Foaming Box; 6 - Foam Finished Product; 7 - Floating Plate
Picture 2: Box Foaming Equipment Manufactured by Hennecke (BFM100/BFM150)
Box foaming process and equipment exhibit characteristics such as simple operation, compact and straightforward equipment structure, low investment, small footprint, and convenient maintenance. These features make it particularly suitable for small enterprises engaged in intermittent production of low-density block foam. However, its drawbacks are also quite evident: lower production efficiency, less favorable production environment, high concentration of emitted toxic gases on-site, necessitating the use of highly effective exhaust and toxic gas purification systems.
To enhance mixing efficiency, some companies have added several vertical and equidistant baffles to the inner walls of the mixing barrel. These baffles, combined with high-speed spiral-type agitators, facilitate high-speed mixing. This approach can to a certain extent reduce laminar flow effects in the mixing liquid and improve mixing efficiency. An example of this is our product, the SAB-BF3302. For the product's appearance and technical specifications, please refer to Picture 3.
Picture 3: Fully Automatic Box Foaming Machine (Sabtech Technology Limited)
This production line comes with both fully automatic computer control and manual control modes. It's suitable for producing flexible polyurethane foam with densities ranging from 10 to 60 kg/cm. Maximum foam output: 180L. Foam height: 1200mm. Mixing power: 7.5kW. Total power: 35kW.
2. Equipment for Open-Cell Foam Preparation
Open-cell polyurethane foam is a functional foam product developed in the 1980s. It possesses a high porosity, a distinct network structure, softness, breathability, and good mechanical strength. It finds wide application as excellent filtration and shock-absorption material in transportation, instrumentation, medical material filtration membranes, and as catalyst carriers in the chemical industry. Filling it into aircraft fuel tanks can suppress oil agitation and reduce the risk of explosions. Impregnating it with ceramic slurry and high-temperature sintering results in a novel open-cell ceramic filter material used in the metallurgical industry.
The preparation of open-cell polyurethane foam involves methods such as steam hydrolysis, alkaline soaking, and explosion. In industrial production, the explosion method is predominantly used. Initially, polyurethane foam of a specific pore size is prepared using the box foaming process. Subsequently, it's placed in dedicated explosion network equipment, filled with explosive gas, and ignited after completely filling the foam body. By utilizing the impact energy and high-temperature heat generated by the explosion parameters, the cell walls of the polyurethane foam are ruptured and fused onto the cell walls, forming a distinct network structure, as shown in Picture 4.
Picture 4: Clearly Networked Open-Cell Foam
Methods like steam hydrolysis or alkaline soaking are used to prepare open-cell foam. However, there are issues of low efficiency, poor quality, and environmental pollution with these methods. They are mainly employed for small-scale production such as laboratory sample testing. Large-scale production primarily uses the explosion method.
ATL Schubs GmbH, a German company, specializes in the research and development of polyurethane reticulated foam and manufactures the ReticulatusTM foam explosion machinery. The explosion chamber of the reticulated foam explosion equipment comes in two forms: cylindrical and rectangular. The former is suitable for cylindrical foam, while the latter is more versatile. It can be used not only for square foam but also for processing reticulated foam from cylindrical foam, as shown in Picture 5. The explosion chamber is constructed from high-quality 100mm-thick steel plates. Operation is controlled by a computer modem, offering features like automatic opening and closing, automatic locking, automatic operation, and automatic alerts. Additionally, remote program design and modification can be facilitated through data transmission sensors.
Picture 5: Polyurethane Foam Reticulation Processing Equipment (ATL Schubs)
During production, foam bodies measuring 3 to 6 meters in length that are intended for reticulation are pushed into the explosion chamber. The chamber's door is closed hydraulically, and the air inside the chamber is evacuated using a vacuum pump. Under computer control, a precise proportion of oxygen and hydrogen gases is introduced, and the gas mixture's ratio is mechanically adjusted based on factors such as foam sample type and network size requirements.
Sensors continuously monitor the process, ensuring that all process parameters are within the specified conditions before controlled detonation is initiated. The explosive force and flame intensity generated by the explosion penetrate through the entire foam body, creating a distinct network structure. After forming, the foam body is cooled, residual materials and waste gases are purged using nitrogen, and the pressure chamber can then be opened to retrieve the reticulated foam. The entire process takes approximately 8 to 10 minutes. The pore diameter of the reticulated foam falls within the range of 10 to 100 pores per inch (ppi) (Note: ppi refers to the number of pores within one inch).
The above provides some insight into the non-continuous production process of polyurethane flexible foam. I hope this information proves helpful to you.
Contact Person: Cynthia Cheung
Contact Number: +86-15687268672
Email: sales@alforu.cn
WhatsApp: +86-15687268672
Company Address: Foshan City, Guangdong Province China