Earth Moving Equipment Spreadsheet Engineering Elements

John Andrew, P.E.

Course Outline

This 4 professional hour online course defines the design and performance equations of several basic earth moving machines

Topics include: Level and Grade Rolling Resistance, Air Drag, Multi-plate Clutch Torque Capacity, Tire Slip, Drive Tire Effective Radius, Wheel Tractive Force, Gear Reduction, Draw Bar Pull, Axle Torque, Ground Speed, Hydraulic Cylinders – Pumps – Motors, and Diesel Power Cycle calculations.

Step-by-step illustrated examples show how to use the spread sheet tools to optimize earth moving equipment drive calculations. 
          
This course is divided into 5 sections.

1. Applications
2. Drive Calculations
3. Diesel Engines
4. Fluid Power                                                                                                         
5. Bucket Arm Forces

The course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.

Learning Objective

At the conclusion of this course, the student will learn how to:

• examine earth moving equipment  applications;                                         
• consider wheel and tractor design features;                                          
• link to the Catapiller home web page;
• solve typical earth moving equipment drive calculations;
• analyze diesel engine performance;
• calculate vehicle road rolling resistance;
• determine rolling radius and tracktive force;
• find multi-plate clutch torque capacity;
• perform hydraulic cylinder and pump calculations;
• calculate the strength of backhoe bucket arms; and
• use Excel’s “Goal Seek” to optimize engineering calculations.
  

Intended Audience

The information will be especially useful to students, engineers, and innovators who need tools for creative earth moving equipment engineering.

Benefit to Attendees

Attendee of this course will be able to calculate and optimize variables in a range of earth moving equipment engineering projects.

Course Introduction

Excel spread sheets are used to calculate and optimize machine design parameters. Calculations have been done with a calculator and written by hand with pen or pencil. Optimizing design values with a calculator is difficult and time consuming. Quite often it is impossible to read and check these documents. As time passes it becomes more difficult to use these documents to make improvements to existing designs if calculations are done by hand.

Course Content

You need to download and study the following spreadsheet:

Earth Moving Equipment Spreadsheet Engineering Elements

DISCLAMER: "This spreadsheet is provided for illustrative teaching purpose only, and is not intended for use in any specific project. Anyone making use of theinformation contained in this spreadsheet does so at his/her own risk and assumes any and all resulting liability arising therefrom."

Spreadsheet Method

Earth Moving Equipment Spreadsheet Engineering is a series of input data and solved output equations in a spreadsheet format. The student will type numerical values of equipment design parameters and Excel or other spreadsheet software will perform the calculations.

Also any input parameter can be found for a target value of a calculated item by using the “Goal Seek” tool in Excel.

For example, the road rolling resistance, weight, mechanical efficiency, and ground speed of a vehicle are typed labeled Input cells and the draw-bar pull and gross power are Calculated by the software automatically.

		Input
	Road Surface:	Asphalt, poor
	Road rolling resistance factor,  Rf =	37	lb/1000
	Gross vehicle weight,  W = W1 + W2 =	116000	lb
	Overall mechanical efficiency of drive train, e =	0.70	-
	Vehicle ground speed,  S =	18.3	miles/hr
		Calculate
	Level road rolling resistance,  Rr =	W * Rf / 1000
	=	4292	lb
	Vehicle ground speed,  s =	S*5280/60
	=	1614.631873	ft/min
	Vehicle draw-bar pull due to rolling resistance,  Pr =	Rr
	=	4292	lb
	Vehicle net power due to rolling resistance,  HPrn =	P*s / 33000
	=	210.0	horsepower
	Vehicle gross power due to rolling resistance,  HPrg =	HPn / e
	=	300.0	horsepower

Course Summary

This course provides Excel spread sheets to calculate a range of basic earth moving machine design parameters. All variables can be adjusted to optimize design goals. Excel print-outs of design parameters and calculated results provide easy to read documentation for checking and future improvements.

Related Links

The United States Patent and Trademark Office Home Page at www.uspto.gov
Provides links to information about all aspects pertaining to invention patents.

Quiz

Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.

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DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.

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