How to Choose Gravity Chute?

These design factors include flow rate, pitch, diameter, material, intended use, and environment. How do you choose the correct spiral gravity let down chute for your product? You test it. And, you test it again. Testing on spiral gravity chutes is very important because all products flow down differently. So come to Astro and experiment on our three samples, here at Astro in Hanover, MN. We would love to assist you in the right design because we care!

If you want to learn more, please visit our website.

• 18&#; OUTSIDE DIAMETER
• 30&#; OUTSIDE DIAMETER
• 54&#; OUTSIDE DIAMETER

Testing the Flow Rate, Pitch and Diameter

It is important to know what flow rate you are trying to achieve. This is in order to design a spiral that can achieve it. Therefore, how your product behaves sliding down the chute is the biggest influence to take into account. The whole system is designed around this key element. The required pitch must be finessed to achieve the desired amount of flow that is needed, given the diameter of the chute.  The flow rate is the function of the width, and the pitch you can get on it.

The right pitch is needed for your product to flow faster, but at a safe speed for minimal breakage of the items. This pitch has much to do with how a flight is stretched. The more you stretch it, the more you get a larger pitch.  However, there is a limit to how much a given size flight can stretch.

Spiral Gravity Chute Material

Our spiral chutes are made with either stainless steel or mild steel. It depends on the intended use and environmental factors, of course.  Do you require food grade vs non-food grade material? Plus, consider temperature and atmosphere when choosing the material and finish.

Common Products to Test on Spiral Gravity Chutes

• Raw and roasted coffee beans
• Peanuts, cashews, nuts & seeds
• Fertilizer
• Packages
• Snacks & candy
• Crackers & cookies
• Dry pasta
• Cereals
• Grains
• Frozen prepared foods, i.e. frozen burgers
• Pet food & animal treats
• Airport baggage handling
• Parcel handling

Collaborative Design on Chutes

Designing spirals is not an exact science. That&#;s why we&#;re here to assist you. All our spiral chutes are customized and fitted precisely to each unique environment and specification. Our team collaborates with our customers on design, fabrication, and implementation. Plus, there are virtually no limitations on the length of our spirals.  However, maximum length of a spiral chute in &#;one piece&#; is 40&#;.

In bulk material handling industries, like steel mill, cement plant, thermal power plant, mining etc ,different kinds of chutes can be found for conveying coal, cement, alumina, sinter dust and other aggregate materials from one transport unit to another. 

1. Chute Definition

Chutes are flat plates, having relatively smooth transferring surface, arranged at different angles to transfer or guide materials along the chute under force of gravity. Many types of chutes exist. According to the force of the ore particles, they can be divided into gravity chutes and centrifugal chutes. If classified by the selected particle size, they can be divided into coarse chutes, ore chutes and slime chutes.

2. Chute Design Consideration

It is important that a chute is designed correctly to ensure the efficient transfer of bulk solids without spillage and blockages and with minimum chute and belt wear. The importance is accentuated with a trend towards higher conveying speeds and ever increasing throughputs. Some common defects in the use of chutes, such as poor material flow, short service life, too much noise, large impact on downstream equipment, leakage, etc.  need to be considered during chute structural design and material selection. 

3. Chute Lining consideration

Chute liner material choice is an essential step during design consideration. Reasons for install chute lining as follows:

3.1.1 To protect the chute structure from abrasion,erosion, temperature imposed by the product.

3.1.2 To protect the product from damage by the chute due to chemical reaction or mechanical damage by the chute.

3.1.3 To increase or reduce friction or otherwise change the velocity of the product.

3.1.4 To process the product during transit along the chute.

4. Chute Lining Selection principle

The selection guide for lining solutions is divided into three sections: wear improvements, flow improvements and noise reduction. Your choice principle will be based on processing conditions, material ,size, shape, drop height, volume, angle of impact,temperature etc.

5. Different Materials for Chute Liner

5.1 Rubber Chute Liner: This is most common material as wear resistant lining,Which may be adhered in sheets or be vulcanized. It is better choice to absorbing noise during conveying materials, but not fit for small particle materials in wet working environment or materials with high temperature.

5.2 Hard Metal Lining of Chutes: Another wear protective linings used popularly . Which include Manganese steel, high chrome steel Chrome molybdenum steels etc. They are characterized by good impact resistance, high temperature resistance, corrosion & wear resistance and easily to be Cutted , bent or crimped, welded and punched.but it is also a heavy and costly choice .

5.3 Alumina Ceramic Chute Liner: ceramic liner tiles have wide types for choice, like alumina ceramic plain tile , welding tile, rubber ceramic wear liner etc. Which kind of applied ceramic liner depends on different working environment including temperature, impact strength etc.

5.3.1 Alumina Plain Tile: it is installed by epoxy resin directly which provides a high shear strength and good resistance to chemical or moisture attack and ageing. Standard sizes or ceramic cutting tiles can be supplied by China ceramic manufacturer like Chemshun Ceramics.  

If you want to learn more, please visit our website Keefam.

5.3.2 Ceramic Welding Tile : It provides excellent abrasion and impact resistance for industrial friction equipment. Is installed by epoxy resin and welding double ways. best wear resistant choice for dynamic operation equipment. 

5.3.3 Rubber Backed Ceramic Wear Plate : a combination of wear resistant alumina ceramics vulcanized in resilient rubber sheet. Which has super wear resistance and impact resistance property from rubber and ceramics. Ceramic shapes can be vulcanized in current market mostly including ceramic cylinder, alumina hexagonal tile, square mosaic tile , ZTA ceramic tile etc .typical ceramic supplier factory like Chemshun Ceramics Company. Rubber ceramic wear liner is mainly installed by welding bolt. good choice as mining chute liner.

6. Maintenance & Replacement of Chute Liner

Chute linings are subject to wear. Sooner or later the liner material will have to be replaced.different chute wear liner materials have different replacement & maintenance ways. Generally good access with enough room for maintenance man should be carefully considered when chute design.

7. How to Install Wear Resistant Ceramic Chute Liner

Step 1: Prepare special designed alumina chute tiles and epoxy resin and other tools

Step 2&#;Install alumina tiles with epoxy resin adhesive in the inner wall of chute 

Step 3: Remove the extra epoxy resin with tools and lightly hit the ceramic liner tile with hammer for air removal

Detailed Installation process :