String wrap machine

Types of string wrap machines

A string wrap machine, also known as a pallet wrapping machine, is used to wrap stretch film around products or pallets to secure, protect, and stabilize the contents during transportation or storage. There are automatic and semi-automatic versions of string wrapping machines, and they come in different types, which are detailed below:

• Rotary Disk Packaging Machine

A rotary disk presents the pallet load for wrapping from a top down to achieve a desired amount of string wrap in a vertically downward wrapping pattern around the product or pallet. It is simple, efficient, and uses gravity to dispense string. A rotary disk string wrap machine is generally used as a part of a packaging assembly line for the strapping of pallets. It helps to avoid using wooden boxes and reduce labor costs. This machine's primary function is to secure loose items by placing a plastic strap around them tightly.

• Turntable Stretch Wrap Machine

A turntable refers to a rotating horizontal platform that spins the pallet load for wrapping. It is a common way of wrapping bottles, cans, jars, etc., at a high speed of up to 60 pallets/hour. In a turntable string wrap machine, an operator places the product on the turntable, which rotates the item while an automated system applies the wrap around it from various heights until it is fully covered.

Turntables can be stationary or actuated by a motor. In the case of a motor-driven turntable, wrapping is faster, and the number of wraps can be pre-determined, especially overhead or crosswise wrapping. Additionally, the wrapping speed can also be controlled to correspond to the turntable's rotating speed.

• Roller Box Wrapping Machine

This is a machine used to wrap products in bulk. Items such as boxes, totaling up to a maximum size of 600 mm x 400 mm x 400 mm and a maximum weight of 10 kg are wrapped around with the help of a film on a roller machine. The film is available in various styles and types. The item to be wrapped is placed in the machine, and once its presence is detected, the wrapping task commences. The box will be wrapped with string, and all four sides will be enveloped by strapping. The entire process will not take more than 5 seconds, and upon completion, the roller machine will reverse and park itself, thereby ending the operation.

• Fully Automatic String Wrapper Machine

A fully automatic string wrap machine is one in which the entire production process from loading the unwrapped pallets to wrapping the strapping film around the loaded pallets to unloading the wrapped pallets is done with the help of automated systems. Operations like side wrapping, top wrapping, bottom wrapping, side reverse wrapping, top reverse wrapping, as well as side and top reverse wrapping can be done with the automatic string wrapping machine indicated for high production.

Such a machine is generally equipped with a computer control system, photoelectric sensors, safety lamps, and a safety fence to offer high-security standards. It is capable of coinciding with other conveyers to form a complete packing line and can also be adjusted to cope with different sizes of pallets. Moreover, it is also possible to perform operations with the help of a foam or corrugated box.

Specifications and Maintenance of String Wrap Machines

The capacities of the String wrap machines may vary depending on their design and purpose. The major specifications of the String wrap machines include the following:

• Machine Dimensions

  Wrap machines are available in a variety of sizes and configurations to accommodate different product shapes and sizes. Those machines have a length and width of around 1m and 0.75m, respectively. A height of about 2m. The machine weighs approximately 270kg.

• String/Material Feeding Mechanism

  The feeding mechanism ensures consistent and controlled feeding of the string/wrap material into the machine. The mechanism includes a motor-driven feed roller with an adjustable speed and tension control. It allows the operator to customize the feeding string's rate and alignment according to specific requirements.

• Wrap Carriage

  The wrap carriage aids in controlling the wrapping pattern and tightness around the product. It consists of an adjustable arm or carriage that moves vertically and horizontally to apply the string at predetermined levels. The carriage's position can be modified to achieve different wrapping configurations depending on the product size and shape.

• String/Warp Tension Adjustment

  Wrap machines have tension control systems to adjust the tightness of the applied string or wrap around the product. This allows fine-tuning the tension to ensure proper securing and prevent damage. It can be achieved through a dial or lever that regulates the tensioning mechanism's speed and pressure.

• Electromagnetic Switch

  The electromagnetic switch controls wrapping automation. It activates or deactivates the wrapping process as the product passes through the machine. This switch is typically a two-position toggle that engages the wrapping mode while suspending other operations.

• Semi-Automatic Functionality

  These wrap machines typically operate under semi-auto functions, which means that the wrapping process is automated. However, manual intervention is required to feed the products into the machine. With this operation, the string is automatically wrapped around the product, and the string carriage returns manually.

Maintenance

Regular maintenance ensures that the string wrap machine functions correctly and reliably, minimizing downtime and maximizing productivity. The users should develop a maintenance schedule that includes routine inspections and servicing to prevent string wrap machine failure. Here are some preventative wrap machine maintenance tips:

• Check the key components of the wrap string machine and replace them if necessary. Monitor and adjust the tension of the wrap string to avoid damaging the wrapped object or the machine itself. Set the wrap string to the desired height and tightness to achieve consistency and uniformity.
• Second, cleaning and lubrication are crucial to the longevity of a string wrap machine. Wrap machines are prone to dust and debris build-up, especially in the moving parts. Cleaning the skid plate, belt drive, and other parts of the machine will ensure that the wrap is tight and secure. Lubricating the sprocket and chains of the machine helps to reduce friction and wear and tear, while also preventing overheating and clogging. Degreasing the machine will stop any foreign contaminants that may compromise its function. Regular cleaning and lubrication not only improve the machine's efficiency but also prolong its lifespan.

Applications of string wrap machines

String packaging machines can be used in different sectors worldwide.

• Food and beverage industry

  In the food and beverage industry, end-line packaging machines are commonly used to package items such as bottles, boxes, and trays. They are also used to package irregularly shaped items such as fruits and vegetables. String packaging machines help to increase production efficiency and extend product shelf life.

• Retail and e-commerce

  In the retail and e-commerce sectors, string packaging machines are used to package individual products such as electronics, cosmetics, and apparel. They help to provide tamper-evident packaging and reduce packaging materials' waste. String packaging machines also help to enhance branding and improve the customer unboxing experience.

• Manufacturing industry

  In the manufacturing industry, string packaging machines are used to package components and parts such as pipes, wires, and insulation. They are also used to package bulk items such as sheets and strapping. String packaging machines help to improve product handling and prevent contamination and damage.

• Logistics and warehousing

  In logistics and warehousing, string packaging machines are used to consolidate and secure packages such as pallets, crates, and cartons. They are also used to bundle goods such as lumber, pipes, and cables. String packaging machines assist with inventory control and streamline order fulfillment processes.

• Pharmaceutical and cosmetic industry

  In the pharmaceutical and cosmetic industries, end-line string packaging machines are used to package individual products such as bottles, jars, and containers. They help to provide tamper-evident packaging, and string packaging machines can improve cleanroom packaging compliance standards.

• Textile and furniture industry

  In the textile and furniture industries, string packaging machines are used to bundle and secure delicate items such as fabrics, linens, and bedding. They are also used to package large and bulky items such as mattresses, upholstered goods, and furniture components. String packaging machines help to protect products and reduce returns due to damage.

How to choose a suitable String Wrap Machine

Choosing the right string automatic wrapping machine requires considering a number of aspects.

• Product size and weight: The amount of packaging and the size, form, and weight of the items to be wrapped should be taken into account when selecting a wrapping machine. Select the machine that can accommodate the size and weight of the items.
• Wrapping speed: The production line's wrapping speed is another important consideration. Make sure the wrapping machine's speed matches the production line's speed.
• Packaging materials: Packaging materials vary in kinds, such as stretch film, shrink film, etc. Select the appropriate packaging material for the item and ensure that the wrapping machine can handle it.
• Automation level: Consider the degree of automation required. Choose a machine with a higher level of automation if one needs to be wrapped out in a large quantity.
• Site requirements: The machine's size and weight must be taken into consideration because the wrapping machine requires a specific amount of room to operate.
• Power supply: Consideration should be given to the power supply since the wrapping machine will require a certain kind of power to operate.
• Costs: Consider the operating and maintenance expenses in addition to the upfront purchase price to select a machine that fits the budget.

String wrap machine Q&A

Q1. Are there any safety issues with using a stretch wrap machine?

A1. Stretch wrap machines have some safety risks that operators must consider. The main dangers are wrapping machines' high weight, moving parts, and loads. People can get serious injuries, like broken bones, if they put their hands near the stretch wrap machine's moving parts, such as the gears and wrapping head. Stretch wrap machines can also cause injuries from heavy loads falling off them or from the machine tipping over. Operators must be aware of these dangers and take safety precautions. They should never put their hands near the moving parts and always make sure the load is stable before stretching wrapping it. The manual should be followed closely so the wrapping equipment is used safely and appropriately.

Q2. Can a stretch wrap machine overwrap?

A2. Overwrap is the process of wrapping an item without a specific number of wraps. It is an issue that many retailers, warehouse workers, and material handlers face when stretch wrapping pallets. Some people think that stretch wrap machines can overwrap pallets intentionally or accidentally, leading to problems. However, this is not true. There is no such thing as stretch wrapping too much or too many wraps. It can be helpful to know that over wrapping might save some money in the long run because the more stretch wrap used on pallets, the more protected products will be, and they will be less likely to get damaged.

Q3. How much power does a stretch wrap machine use?

A3. The amount of power used by a stretch wrap machine depends on several factors, including the size and model of the machine, its wrapping speed, the thickness of the stretch film used, and the efficiency of the power source. In general, stretch wrap machines are designed to be power efficient, and the amount of power they use is typically measured in kilowatts per hour (kWh) used. On average, a stretch wrap machine uses around 1.5 - 2.5 kWh. It uses less power as its wrapping speed is increased.

Q4. How many pallets can a stretch wrap machine make in an hour?

A4. The number of pallets that a stretch wrap machine can wrap in one hour depends on several factors, including the speed of the wrapping machine, the size of the pallet, and the efficiency of the operator. Stretch wrap machines have different speeds. A standard stretch wrapping machine wraps pallets at a speed of about 12 - 30 pallets per minute. An average stretching wrapping machine can wrap around 20 - 30 pallets in one hour. The speed is 12 - 15 pallets per minute for more complex jobs like multi-pallet stretch wrapping combinations.

Q5. Does film type affect how a stretch wrap machine is wrapped?

A5. The kind of stretch film used to wrap items significantly impacts how the stretch wrap machine does the wrap. Different types of stretch films have other qualities, which can give parts distinct characteristics. For example, some films are made to extend more than others, which means that more pallets can be wrapped with one stretch of the film. Also, films with different levels of cling will stick to themselves and other film layers at different rates when wrapping pallets is done. Moreover, the thickness of the stretch film also affects how the stretch wrapping machine works. It determines how many layers are used to wrap one item and how long it takes to wrap it.