Timber or wood processing industry relies much on efficient automation production. However, the properties and characteristics of wood make it complicated for handling.
The application of vacuum technology in various industries works well. Meanwhile, can it handle the problem with timber well? Do suction cups work on wood?
Vacuum suction cups and the woodworking industry
The wood industry is a significant sector due to people’s fascination for wood’s beauty, properties, and application. However, handling them is not always straightforward as they are bulky and heavy.
They have rough surfaces and come in various shapes (for example, sheets, boards, or planks). Wood manipulation used to be particularly challenging before applying vacuum technology.
How do suction cups work on wood?
The application of vacuum suction helps lift and handle wood effortlessly. The suction cups can securely adhere to wood surfaces and easily be removed when needed.
The whole process is done by taking advantage of vacuum pressure, without using any chemicals or leaving any residue or marks.
The difference in air pressure within and outside of the suction cups creates a holding force and helps gently handle any wood planks, sheets, or boards.
Some benefits of the suction cup for wood surfaces can be named as follows:
- safely work on particular characteristics of wood surface
- suitable for diverse porosity and different finishing (polished, rustic) wood pieces
- efficient handling of any wood shapes
- easily moving heavy and bulky loads
- leave no deformation of thin-walled products like wood pallets
Requirements when choosing suction cups for wood
The vacuum cups can fasten securely against the wood surface by working together with the vacuum generator to create the holding/lifting force. The lifting force for each suction cup is determined by cup diameter and final vacuum level.
In wood lifting and transporting, the weight of the wood is rarely an issue because most wood applications offer sufficient surface area for the vacuum cups to stick on. Instead, providing a secure seal while leaving no marking is more concerning.
Therefore, the sizes and materials of vacuum suction cups for wood surfaces should be chosen correctly and wisely to ensure meeting this requirement while being long-lasting for cost-saving.
The suction cups for wood are available in different shapes and diverse materials. In order to choose the right cups, there are several criteria to be taken into consideration. Suction cups for wood selection will be discussed in more detail in the next paragraph.
Suction cups for wood according to wood materials
In the woodworking industry, there are some common wooden panel materials. Each of them has physical characteristics and surface finishes.
For example, Medium Density Fiberboard (MDF) has a high density and smooth surface, while High-Density Fiberboard (HDF) is stronger and harder. Both MDF and HDF are thicker than veneer.
According to the surface finish of the wood workpiece, the suction cup for wood surface can be categorized into two designs.
Flat Suction Cup
A flat suction cup is ideal for a uniform and smooth surface. With a round shape, an industrial flat suction cup is perfect for handling wood panels or wood sheets.
Low inner volume of flat suction cups allows air to be removed quickly, enabling them to carry workpieces in a short time and be suitable for short-cycle presses.
Besides offering universal suction cups with diameters from 3mm to 810mm, vacuum technology experts like EUROTECH can offer components (for example, special sealing foam, suction cup with long sealing lip and valve components to reduce leakage) to support safety lifting with heavy MDF/HDF wood boards.
Bellow Suction Cup with Foam
Rough or textured surfaces happen to have more aggressive features such as being concave/convex, uneven, curved, and arched.
One example in furniture design is doors with cut-outs for windows. The air leaking can be a problem for flat suction cups.
Solutions will be bellow suction cups with foam. The cup design itself has been made to provide good support in gripping rough surfaces. Closed-cell foam deforms into the surface irregularities and offers a better seal than regular rubber.
Bellow suction cups also come up with 1.5 folds and 2.5 folds to best lift undulating surfaces such as particle board, laminate flooring, and OSB.
Clients can choose between round and oval shapes depending on how narrow, or oblong the workpieces are. The oval shape is best used for wood sticks or beams.
FAQ about vacuum suction cups in the woodworking industry
What are some problems that frequently occur when choosing vacuum suction cups in the wood processing industry?
How big should the suction cup be?
Suction cup diameter depends on the requirements of the holding force and breakaway force problem to be solved.
Need a blower or a pump?
The answer is determined by the specified application. Vacuum blowers handle extremely porous materials while vacuum pumps are mainly used for handling non-porous materials.
How many degrees of vacuum does it need?
For inclined surfaces, from 5 to 30° depending upon bellow suction cup diameter.
The level of the porousness of the adsorbate?
Unlike other materials, wood can be porous and non-porous according to its vessel elements (or pores).
Initially, wood can be divided into three main categories (e.g. ring-porous, diffuse-porous, and semi-ring-porous or semi-diffuse-porous) depending on porosity.
In addition to that, there are also a few other factors pertaining to pores to consider in wood identification as follows:
- pore arrangement (e.g. solitary, multiple, diagonal, straight or wavy tangential, and so on)
- pore size (from small as <50µm, to large as 200µm or more)
- pore frequency (from very few as 5 vessels/mm2, to very numerous as more than 100 vessels/sq mm)
- pore contents
The porousness affects the vacuum pressure used to lift the wood object as air will leak into the vacuum.
To maintain gripping, a high flow of air, at a low level of vacuum, must be maintained to compensate for the air leaks.
The recommended vacuum range is from 30 to 80 percent where porous materials should be 30 to 55 percent vacuum and air-tight surfaces should be 55 to 80 percent vacuum.
How to prevent the wood from adsorption, which results in the suction of two “woods”?
Wood adsorption can be prevented by using large-area gripper modules integrated with a separating function. This function ensures a restricted flow of compressed air goes between the layers, then only one piece can be lifted at a time.
How to suction thin wooden layers products such as wood veneer?
The characteristics of veneers are thin, light, and brittle so that they can be easily damaged or cracked. They require a large-area gripping system providing gentle handling when unstacking and transporting.
What suction material does the woodworking industry use?
Depending on the application conditions (for example, numbers of load, areas of application, life expectancy, material design availability, and working environment) the selection of the suction material can vary.
NBR (Nitrile butadiene rubber), Silicon, Fluoro rubber, PU (Polyurethane) are the most common in the material list of vacuum suction cups used in the woodworking industry.
In general, wood surface texture and porosity determine the selection of the cup material and model. Additional components are used based on preference and design needs.
This article offers a general guide. To select an appropriate vacuum suction cup for a safe industrial working environment, professional assistance is recommended.
To help your business best answer the question of whether suction cups work on wood for specific applications, contact a professional vacuum cups provider for advice.
EUROTECH, with more than 20 years of experience in providing industrial vacuum solutions, will help businesses find the right technical solution.