web analytics
  • Introducing the JMS Learning Center
  • JMS Testimonials
  • JMS Videos
  • JMS News
  • Rep Portal
  • Careers
JMS
  • Home
  • JMS Products
    • JMS Product Families
      • All JMS Products
      • All Mega-TREATMENT Products
      • All Bio-HANDLING Products
      • All Delta-SEPARATION Products
    • Mega-TREATMENT
      • Mega-FLOCS
      • Mega-BEARING
      • Mega-FLOC (HPWF)
      • Mega-FLOC (VPWF)
      • Mega-FLOC (WBF)
      • Mega-SETTLER
      • Mega-SETTLER (Wastewater)
      • Mega-VAC
      • Mega-SCRAPER
      • Mega-SYSTEM
      • Mega-TROUGH
      • Mega-WALL
    • Bio-HANDLING
      • Bio-HANDLING
      • Bio-HOPPER
      • Bio-BELT
      • Bio-SCREW
      • Bio-VALVE
      • Bio-GATE
    • Delta-SEPARATION
      • Delta-CLASSIFIER
      • Delta-COMPACTOR
      • Delta-SKIMMERS
      • Delta-SKIMMER (Scum Pipe)
      • Delta-SKIMMER (Helical Skimmer)
      • Delta-SKIMMER (Paddle Wheel Skimmer)
      • Delta-DECANTER
      • Delta-PUMP
      • Delta-TSV
    • Eco-AIR
      • Eco-AIR
  • Aftermarket Parts
  • Learning Center
  • About/News
    • About JMS
      • About JMS
      • The JMS Way
      • Testimonials
      • Careers
    • JMS News
      • JMS News
      • JMS Videos
  • Contact
    • Find a Rep
    • Contact JMS

Screw Conveyor Horsepower

06
Mar, 2020
By Andrew Gaiser
Screw Conveyor Horsepower
  • Learning Center,Product Basics,Screw Conveyors
  • No comments

Once it has been determined that a Screw Conveyor will best fit your application, and the type of screw conveyor you will use (shafted or shaftless), a calculation will be completed to specify the horsepower that will be needed to meet the needs of the application.  Simply put, horsepower is a measure of the rate at which work is done. In the case of the screw conveyor it is a measure of the power needed to move the material in question a defined distance and elevation.

Screw conveyor horsepower requirements are directly defined in the CEMA Standard No. 350 – Screw Conveyor for Bulk Materials.  To calculate the horsepower needs for a given application it is first important to understand the needs of the application. This includes the mass flow rate requirements in lbs/hr, the bulk density in lbs/ft3, the length of the conveyor in ft, and whether this will be a batch or constant application, and horizontal or inclined conveyor, and the safety factor desired.    The operating speed to carry the required amount of material in RPM must also be calculated.

A conveyor with horsepower that is undersized for the application will not be able to convey the material, will certainly not be able to handle any “slugs” or unexpected volume of material, and may result in motor failure and loss of productivity.  One that is oversized will use more power than needed and have excessive costs.

Two components make up the horsepower requirements, first is the hpf, the horsepower needed to overcome friction, and second is the hpm or horsepower needed to convey the material.  Hpf represents the horsepower needed to turn, overcoming friction,  the empty equipment and is affected by the conveyor length, speed, and factors that represent the resistance of the hanger bearings and screw diameter.  These factors have been predetermined by analysis of data and are published by CEMA. 

Click to Enlarge

L= Total Length (ft)

N= Operating Speed (rpm)

Fd= Screw Diameter Factor (CEMA Table 3.2)

Fb= Hanger Bearing Factor (CEMA Table 3.1)

Hpm is affected by such things as the capacity and length, and material density.  These are independent variables determined by the location and process.

Click to Enlarge

C= Capacity (ft3/hr)

W= Density of Material as Conveyed (lbs/ft3)

Ff= Flight Factor (CEMA Table 3.3)

Fm= Material Factor

Fp= Paddle Factor (CEMA Table 3.4)

The total horsepower requirement is calculated as the sum of these two factors allowing for an overload factor and the overall drive efficiency.

Click to Enlarge

E= Drive Efficiency (CEMA Table 8.1)

Fo= Overload Factor (CEMA Figure 3.1)

Hence you have the required horsepower for the conveyor in question.  It is important to note that all of the components of the screw conveyor must be sized to handle the full motor horsepower.  Your conveyor supplier will help you in determining the right conveyor and the horsepower needed for your application.

*Reference CEMA Standard No. 350 Screw Conveyor for Bulk Materials

About Andrew Gaiser

Andrew Gaiser is employed in the JMS Engineering Department in the role of Product Engineer. Andrew is a graduate of Virginia Tech in Mechanical Engineering, and has had previous experience in design at Controls Southeast Inc. As a former competitive runner, he is still an avid runner and also enjoys rock climbing.

Leave A Reply Form Cancel reply

Search JMS

Back to the Learning Center

  • Learning Center

Material Handling Products

  • Material Handling Systems
  • Live Bottom Hoppers
  • Belt Conveyors
  • Screw Conveyors
  • Slide Gates

Learn by Product Groups

  • Water Treatment Systems
  • Material Handling Systems
  • Separation Systems
  • Aeration Systems

Learn by Topic

  • Product Pricing
  • Product Comparison
  • Product Basics
  • Top Manufacturers
  • JMS Presentations
  • JMS Videos

Recent Posts

  • Biosolids Truck Receival Bins Product Basics
    Below is a recent protestation put together by Greg Hyde to […]
  • Shafted vs. Shaftless Live Bottom Screws
    Question: Which is the best type of screw spiral to use in […]
  • Screw Conveyors for Raw Screenings – Q & A
    As a Product Manager at JMS, one of my jobs is to work with […]
  • Screw Conveyor Horsepower
    Once it has been determined that a Screw Conveyor will best […]
  • Biosolids Storage Selections: Hoppers, Silos, Bins
    Biosolids require storage for all types of materials from […]
  • When to use a Vertical Screw Conveyor
    Screw conveyors are compact in design and easily adapt to […]
  • Typical Shafted Screw Conveyor Wear Parts
    Screw conveyors are available in both shafted and shaftless […]

JMS Site Map

  • Home
  • Learning Center
  • JMS Products
  • Mega-TREATMENT
  • Bio-HANDLING
  • Delta-SEPARATION
  • Eco-AIR
  • Aftermarket Parts
  • Rep Portal
  • Find a Rep
  • Contact JMS
  • Site Map
  • Privacy Policy

Bio-HANDLING

  • Bio-HOPPER
  • Bio-BELT
  • Bio-SCREW
  • Bio-GATE
  • Bio-VALVE

Mega-TREATMENT

  • Mega-FLOCS
  • Mega-BEARING
  • Mega-FLOC (HPWF)
  • Mega-FLOC (VPWF)
  • Mega-FLOC (WBF)
  • Mega-SETTLER
  • Mega-SETTLER (Wastewater)
  • Mega-VAC
  • Mega-SCRAPER
  • Mega-TROUGH
  • Mega-WALL
  • Mega-SYSTEM

Delta-SEPARATION

  • Delta-CLASSIFIER
  • Delta-COMPACTOR
  • Delta-SKIMMERS
  • Delta-SKIMMER (Scum Pipe)
  • Delta-SKIMMER (Helical Skimmer)
  • Delta-SKIMMER (Paddle Wheel Skimmer)
  • Delta-DECANTER
  • Delta-PUMP
  • Delta-TSV

Eco-AIR

  • Eco-AIR

About JMS

  • About JMS
  • The JMS Way
  • JMS Videos
  • JMS Testimonials
  • JMS News
  • Careers

Search JMS

Follow JMS

  • Facebook
  • Twitter
  • Linkedin
  • Youtube

Contact JMS

Address:
Physical Address:
5120 Westinghouse Blvd.
Charlotte NC 28273

Shipping Address:
P.O. Box 38778
Charlotte, NC 28278

Phone:
704-554-8397

Fax:
704-554-9113

E-mail:
sales@jmsequipment.com

Copyright © 2019. Jim Myers & Sons, Inc. All Rights Reserved.