エンジニアリングと知識

基礎とエンジニアリング

Pump Construction (Part1)

In 1689 the physicist Denis Papin invented the centrifugal pump and today this kind of pump is the most used around the world. The centrifugal pump is built on a simple principle: Liquid is led to the impeller hub and by means of the centrifugal force it is flung towards the periphery of the impellers. The construction is fairly inexpensive, robust and simple and its high speed makes it possible to connect the pump directly to an asynchronous motor.

腐食とは?

Corrosion is usually referred to as the degradation of the metal by chemical or electrochemical reaction with its environment, see figure 1. When considered broadly, corrosion may be looked upon as the tendency of the metal to revert to its natural state similar to the oxide from which it was originally melted. Only precious metals, such as gold and platinum are found in nature in their metallic state. – Types of corrosion – Uniform corrosion – Pitting corrosion – Crevice corrosion – Intergranular corrosion – Selective corrosion – Erosion corrosion – Cavitation corrosion – Stress corrosion cracking (SCC) – Corrosion fatigue – Galvanic corrosion

膨張弁の選択

The expansion valve regulates the amount of compressed liquid refrigerant moving into the evaporator. It removes pressure from the liquid refrigerant to allow expansion or change of state from a liquid to a gas in the evaporator. In order to properly select Expansion Valves one should pay attention to the items that we mention in this post.

水管と火管ボイラー

Water tube boilers and fire tube boilers are two different types of steam boilers that are commonly used in industrial and commercial applications. Both types of boilers use a system of tubes to generate steam, but they differ in the way that the tubes are arranged and the way that the hot gases from the burner pass through the tubes.

Water Hammer (Part1)

Under unfavorable circumstances, damage due to water hammer may occur in pipelines measuring more than one hundred meters and conveying only several tenths of a liter per second. But even very short, unsupported pipelines in pumping stations can be damaged by resonant vibrations if they are not properly anchored. By contrast, the phenomenon is not very common in building services systems, e.g. in heating and drinking water supply pipelines, which typically are short in length and have a small cross-section.

キャピラリーチューブ冷凍

A refrigeration capillary tube is a small, narrow tube that is used in refrigeration systems to control the flow of refrigerant. It is typically made of copper or other highly conductive metal, and is used in conjunction with a compressor, evaporator, and condenser to transfer heat from one location to another. The capillary tube is placed between the evaporator and the compressor in the refrigeration system, and it acts as a metering device to control the flow of refrigerant.

冷蔵式と計算

These formulas are commonly used in the field of refrigeration and air conditioning to calculate various performance parameters of a refrigeration system such as compression work, compression power, coefficient of performance, net refrigeration effect, capacity, compressor displacement, heat of compression, volumetric efficiency, and compression ratio. These formulas are based on the thermodynamics principles and are generally used to evaluate the performance of the refrigeration system and to optimize its design.

The coefficient of velocity (Cv)

Cv, or coefficient of velocity, is a measure of the flow capacity of a valve. It represents the number of gallons per minute (GPM) of water at 60°F that will flow through a valve with a one-inch opening at a pressure drop of one pound per square inch (PSI). Cv can be calculated using various formulas, such as the one based on water at 60F and one that takes into account the specific gravity of the fluid. Cv is a theoretical value and it may vary depending on the actual conditions of the valve. When selecting a valve for a specific application, it is important to consider the Cv in relation to the flow rate and pressure drop requirements of the system, as well as other factors such as ease of maintenance, cost, and safety.

パイプ断熱ガイドライン

パイプの断熱は、エネルギー効率、温度制御、結露制御、騒音低減、安全性を維持するために非常に重要です。 ASHRAE は、規格 90.1 でさまざまなパイプ サイズと温度範囲に応じた特定の推奨厚さを提供しています。 ASHRAE 規格に基づいてパイプ断熱材を選択する場合は、温度、パイプのサイズ、環境への配慮、耐火性、エネルギー効率を考慮することが重要です。

冷媒配管 – パート 2

In this post, we will be continuing our comprehensive training on how to size refrigerant piping. We will cover all the important aspects of this process, including determining the pipe size, pressure drop, and other factors. We will also discuss topics such as sizing refrigerant lines, equivalent length for refrigerant lines, and how to determine equivalent length. With this training, you will have the knowledge and confidence to size refrigerant piping accurately and correctly in any situation.


標準とコンプライアンス

HVAC ダクト設計: ダクト継手の摩擦損失

Complete guide to HVAC duct fittings friction loss using Carrier standards covering loss coefficients, pressure drop calculations, and system optimization for efficient air distribution design.

HVACダクト設計:ダンパー、減衰器、コイル摩擦損失

Complete guide to HVAC dampers, attenuators, and coils friction loss using SMACNA standards covering pressure drop calculations, component selection, and system optimization for efficient air distribution design.

HVACダクト設計:ダクトラウンドから長方形の同等物

Complete guide to HVAC round-to-rectangular duct equivalency using ASHRAE standards covering conversion formulas, performance considerations, and system optimization for space-constrained installations.

HVACダクト設計:ダクト摩擦損失

Complete guide to HVAC duct friction loss calculations using ASHRAE standards covering friction charts, pressure drop analysis, and system optimization for efficient air distribution design.

HVACダクト設計:ダクト圧力分類

Complete guide to HVAC duct pressure classification using SMACNA standards covering pressure class selection, construction requirements, and testing protocols for safe and efficient ductwork systems.

HVACダクト設計 - 汚染物質抽出ダクトのサイジング(煙|グリース|ガス|乾燥&湿ったほこり)

ASHRAE’s Pocket Guide lists minimum conveying velocities that keep contaminants airborne while they travel through exhaust ductwork. Table 2.9 (2013 edition, Ch. 02, pp. 60

HVACダクト設計:商業用キッチンダクトサイジング

Complete guide to commercial kitchen duct sizing using ASHRAE and NFPA standards covering exhaust hood design, grease management, fire safety, and make-up air systems for food service operations.

HVACダクト設計:速度とノイズ基準(NC)によるダクトサイジング

Complete guide to HVAC duct sizing using velocity and noise criteria with ASHRAE and CIBSE standards covering acoustic design, velocity limits, and noise control for sensitive applications.

HVACダクト設計:等しい摩擦法によるダクトサイジング

Complete guide to HVAC duct sizing using the equal friction method with SMACNA and ASHRAE standards covering calculation procedures, friction rate selection, and system optimization for effective air distribution design.

HVACダクト設計:ダクトサイジングSmacnaの推奨

Complete guide to HVAC duct sizing using SMACNA recommendations covering equal friction, velocity, and static regain methods with design calculations and system optimization for effective air distribution.


デジタルツールとリソース

HVAC-R Load Calculator: Your Essential Tool for Accurate System Sizing

Our new web-based calculator combines sophisticated engineering principles with an intuitive interface, making accurate load calculations accessible to everyone from students to seasoned professionals. Unlike basic square-footage estimators, our tool considers the multitude of factors that influence heating and cooling requirements.

Interactive Psychrometric Chart

The aim of this web app is to create an interactive psychrometric chart on which you can project a range of comfort metrics as well as mapping weather data or room air conditions calculated using EnergyPlus. You can add or remove lines for a range of different metrics or highlight them individually to assist with dynamic explanations or presentations.

HVAC-R Financing Made Simple: Introducing Our Smart Equipment Calculator

we’ve developed a comprehensive HVAC-R Equipment Financing Calculator that goes beyond basic loan calculations to include industry-specific considerations like energy savings, equipment efficiency, and available tax incentives

Download Weather Design Conditions (ASHRAE)

Discover ASHRAE Handbook weather stations with our comprehensive search tool. Optimize HVAC and equipment design, sizing, distribution, and installation for residential, commercial, and industrial applications. Enhance your energy-related projects across various sectors, including agriculture, by leveraging accurate climatic data.