Notes, summaries, assignments, exams, and problems for Technology

Classification of Consumption Sites

Consumption sites are primarily classified as:

• Residential or Commercial: Buildings intended for living or business purposes.
• Office: Buildings specifically designed for office use.
• Industry-Specific: Facilities tailored to the needs of a particular industry.
• Industrial Concentration: Areas designated for a cluster of industries.

Load Forecasting

Load forecasting considerations for different building types:

• Housing: Residential buildings.
• General Services: Common areas and shared facilities.
• Shops and Offices: Commercial spaces and office buildings.
• Garages: Parking facilities.

Degree of Electrification

• Basic Electrification: Designed to meet primary usage needs, allowing for common household equipment (5750 W).
• High Electrification:

Development and Implementation of Demolition

1. Dismantling of industrial equipment.
2. Demolition or removal of bodies and covered ledges.
3. Demolition or removal of the deck.
4. Demolition of elements at each plant: interior partition walls, curtain walls, and cargo.
5. Demolition of structural elements: forged with beams, reinforced concrete slabs (one-direction, two-directions), beams, brackets, domes.

Types of Demolition

According to Procedure

1. Element by element.
2. With collapse.
3. Mixed or combined.

According to Media

1. Manual.
2. Mechanical.
3. Thermal.
4. By explosives.

Design of a Sanitation Network

• If the network is public: Mixed.
• If two networks (wastewater and stormwater): Separator system.

Basic Sanitation Network Requirements

1. Dispose of water seal to prevent the passage of air.

Types of Ferrous Metals

Ferrous metals are primarily industrial iron, steel, and cast iron.

Industrial Iron

Industrial iron has a low carbon content and inadequate mechanical characteristics, making it rarely used in industries.

Steel

Steels are ductile and malleable. Mechanical strength, hardness, and brittleness increase with carbon content, while weldability decreases with the percentage of carbon. Steel is also prone to rust. There are two main types of steels: carbon steels (those with low content of other elements) and alloy steels (containing other elements).

Various elements communicate a range of properties to steel. These include sulfur, cobalt, chromium, manganese, molybdenum, nickel, lead, silicon, vanadium, and tungsten.

Cast Iron

Casting... Continue reading "Ferrous Metals: Types, Properties, and Steelmaking Processes" »

Machines and Energy

Machines use energy to perform useful work.

Fossil Fuels

Fossil fuels, such as coal, oil, and natural gas, can be burned to release heat energy.

Nuclear Fuel

Nuclear fuel, including uranium and radioactive materials like plutonium, can undergo fission reactions to produce electricity.

Renewable Energy

Renewable energy sources were the first to be used historically, powering machines such as mills.

Water Wheel

A water wheel utilizes the energy of flowing water through a system of blades. It has various applications, such as grinding wheat to make flour.

• Wheels running low: These are the simplest type, with the bottom submerged. The force of the water current moves the wheel.
• Current average: This type of wheel is used when the current

Rigid Couplings

Rigid couplings are used when trees are on the same axis and do not change their position. There are several types:

• Flange Couplings: These are based on placing two flanges on the ends of the shafts so that when tightening the screws, the flanges are joined together.
• Clamp Couplings: These use a tapered internal conical piece that is compressed when tightening the screws, pressing the two pieces together.

Mobile Couplings

Mobile couplings are designed to accommodate some degree of misalignment or movement between shafts.

• Couplings with Gaskets: These absorb minor irregularities through elastic rotation and allow for very little misalignment.
• Universal or Cardan Joints: These transmit motion between two non-aligned trees.
• Homokinetic

Laying Ground Facilities Project

The process involves several key steps:

• Research
• Determination
• Design
• Calculation of resistance
• Computation step of crack on the outside of the installation
• Calculation of contact and step voltages inside the installation
• Checking
• Research
• Correction

Wenner Method

The Wenner method is the most used and recommended technique to measure the resistivity of the ground.

High Voltage Open Circuit Procedure

1. Open the switch.
2. Open the disconnectors.

High Voltage Circuit Closing Procedure

1. Close the disconnectors.
2. Close the switch.

Lockout or Interlock Device

A lockout or interlock device is the set of operations aimed at preventing the operation of a device and maintaining it in a given position.

Verification of Absence of Tension

It is necessary... Continue reading "Grounding Systems & Electrical Safety Procedures" »

Operation of Drive Elements, Control, and a Hydraulic System

Hydraulic Group

Generates hydraulic energy. A motor-driven pump converts energy. If the flow encounters resistance, there is pressure to fit in the pressure relief valve. Fluid drains back to the tank through a filter. The tank stores and conditions the oil.

Hydraulic Actuators

Converting hydraulic energy into mechanical energy. Conversion by rotating movement (hydraulic motor, which is at the pump's traverse), or linear movement cylinder.

Cylinders:

1. Single-acting
2. Double-acting
3. Special
4. Plunger (double-acting piston rod makes)
5. Differential (double-acting 2:1 ratio S side plunger rod side)
6. Equilibrated (dual stem)
7. Telescopic (short length, big race)

Valves

Responsible for controlling flow regulation... Continue reading "Understanding Hydraulic Systems: Actuators, Valves, and Control" »

Technology Project Process and Building Materials

Technology Project Process

• Problem Analysis

  Tools for analysis, potential improvements, relevant knowledge, ideas, and theories.

• Technical Project

  • Idea Generation

    Each participant creates a sketch or drawing with a brief explanation detailing the object, its components, and operation.

  • Idea Selection

    Choose the most appropriate idea based on criteria such as potential for improvement, feasibility with available resources, frequency of suggestion, or innovative solutions to the problem.

  • Final Design

    Create detailed drawings, plans, and views of the object.

  • Material Selection

    Choose appropriate materials for each part considering technical, aesthetic, economic, and ecological factors, utilizing available resources.

Electric Brake Dynamometer

The electric brake dynamometer transforms energy absorbed from the engine into electrical energy, unlike hydraulic brakes which convert it into heat. It consists of a stator (or inductor) that can pivot on a support resting on the bench via ball bearings, allowing for damping fluctuations around a shaft attached to the rotor (or armature) of the dynamo. The housing is mounted on a lever arm that collects the load weight, which determines the resistance torque measured on the dynamometer. On the opposite side of the housing, an extension of the lever arm carries a counterweight to balance the machine at rest.

Prony Brake: A Historical Perspective

The Prony brake is the simplest and most rudimentary dynamometer, and it... Continue reading "Engine Testing Dynamometers and Fuel Mixture Basics" »

Simple Machines: Levers, Pulleys, and Gears

Levers

Used since ancient times, a lever is a mechanism consisting of a rod attached to a frame by a point called the fulcrum, which enables the bar to rotate. The force to be overcome is called resistance (R), while the driving force applied is called effort (P). The distances from the fulcrum to these two forces are called the resistance arm (AR) and the effort arm (AP), respectively.

Levers are classified into three types based on the relative positions of the fulcrum, resistance, and effort:

• First-Class Lever

  The fulcrum is located between the resistance (R) and the effort (P).

• Second-Class Lever

  The resistance (R) is located between the fulcrum and the effort (P).

• Third-Class Lever

  The effort (P) is applied