DUE-60WKS-CE240/22PO 模块用于控制传输速度 Kollmorgen
eally价值工程；以小化生命周期为目标
成本经常受到影响。这个国家有足够的建筑物
华丽的装饰和不舒适的居住者证明了这一说法。正如约翰·罗斯金多年前所说：
付出太多是不明智的，但付出太少更糟糕。当你
付出太多你会损失一点钱。当你付得太少的时候，你有时会失去一切，因为你买的东西不能
做它被买来做的事。商业平衡的普通法
禁止付出一点而得到很多，这是不可能的。如果你处理
对于出价低的投标人，好为你的风险增加一些东西。
如果你这样做，你将有足够的钱买更好的东西。
4.销售佳解决方案。这又回到了许多人的弱点
工程师和设计师：他们有伟大的想法，但他们有困难
现在是实施这些想法的时候了。通过首先了解设备或系统的用途，然后产生好的数据来理解
当前的性能，以及终开发一个具有记录可行性的替代方案，极大地支持了销售工作。
气体强制通风炉是HVAC装置的一个示例，该装置具有：
随着时间的推移，通过价值工程进行了改进。的目的
熔炉现在和以前一样，是利用燃料的化学能来加热
环境，即加热房屋。但是，20世纪30年代的熔炉与今天的高科技熔炉有着天壤之别，它有铸铁或重金属耐火材料衬里的火箱和直径为4英尺的阀盖。尺寸减少，容量增加，重量增加
相对成本降低，燃料燃烧效率提高，可靠性提高。
泵和风扇的变速驱动装置具有：
已改进到通用应用的程度。经营成本
降低速度以“匹配负载”的优势已为人所知
在工业中使用了很长时间，但技术需要时间
为商用开发可靠、低成本、变速控制器
例如现在用于HVAC应用中的变频驱动器。
如果价值工程似乎与1.2节中的问题解决共享一些共同的分析技术，则双重呈现是有意的。这两种讨论都是解决问题和改善服务的方法。一个是对导师的例子的解释，
暖通空调工程基础：1部分
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暖通空调工程基础：1部分5
二种是公开记录的正式程序。暖通空调
如果系统设计师能够致力于
分析思维过程，定义问题，提出解决方案，确定佳方法，后以可信和令人信服的方式提出解决方案。
1.4规范和规定
任何暖通空调设计师都不应首先了解并熟悉管理和规范建筑施工、产品设计和制造、工程师资格的各种规范和条例，然后才承担设计任务
实践等。规范通常在以下基础上具有法律效力
保护公共安全和福利。可施加处罚
对于违反既定规范的人，以及违规装置
可能会被谴责，并被视为不适用于强制执行
当局。作为年轻的设计从业者，我们被建议“卷曲”
直到我们完全熟悉
它的戒律。
代码是particu
DUE-60WKS-CE240/22PO 模块用于控制传输速度 Kollmorgen
DUE-60WKS-CE240/22PO 模块用于控制传输速度 Kollmorgen
eally value engineering; for the objective of minimized life cycle
cost is often compromised. There are enough buildings in this country
with fancy finishes and uncomfortable occupants to attest to this assertion. As John Ruskin said many years ago:
It is unwise to pay too much but it is worse to pay too little. When you
pay too much you lose a little money. When you pay too little you sometimes lose everything, because the thing you bought was incapable of
doing the thing it was bought to do. The common law of business balance
prohibits paying a little and getting a lot—it can’t be done. If you deal
with the lowest bidder it is well to add something for the risk you run.
And if you do that you will have enough to pay for something better.
4. Sell the best solution. This ties back into a weakness of many
engineers and designers: They have great ideas, but they have a hard
time getting these ideas implemented. By first understanding the purpose of a device or system, then producing good data to understand
current performance, and finally developing an alternative with documented feasibility, the sales effort is greatly supported.
Gas forced-air furnaces are an example of an HVAC unit which has
been improved over time by value engineering. The purpose of the
furnace now, as before, is to use the chemical energy of a fuel to warm
the environment, i.e., to heat the house. But there is a world of difference between the furnace of the 1930s, with its cast-iron or heavymetal refractory-lined firebox and 4-ft-diameter bonnet, and the hightechnology furnaces of today. Size is down, capacity is up, weight is
down, relative cost is down, fuel combustion efficiency is up, and reliability is debatably up.
Variable-speed drives for pumps and fans are devices which have
been improved to the point of common application. The operating-cost
advantages of reduced speed to ‘‘match the load’’ have been known
and used in industry for a long time, but technology has taken its time
to develop reliable, low-cost, variable-speed controllers for commercial
motors, such as variable-frequency drives now used in HVAC applications.
If value engineering seems to share some common analytical technique with Sec. 1.2 on problem solving, the dual presentation is intentional. Both discussions are approaches to solving problems, to improving service. The first is an interpretation of a mentor’s example,
HVAC Engineering Fundamentals: Part 1
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HVAC Engineering Fundamentals: Part 1 5
the second is a publicly documented, formal procedure. The HVAC
system designer will benefit greatly if she or he can commit to an
analytical thought process which defines the problem, proposes solutions, identifies the optimum approach, and finally presents the solution in a credible and compelling way.
1.4 Codes and Regulations
No HVAC designer should undertake a design task without first having an awareness of and hopefully a working familiarity with the various codes and ordinances which govern and regulate building construction, product design and fabrication, qualification of engineers in
practice, etc. Codes generally are given the force of law on the basis
of protecting the public safety and welfare. Penalties may be applied
to those who violate established codes, and the offending installation
may be condemned and regarded as unsuitable for use by enforcement
authorities. As young design practitioners, we were advised to ‘‘curl
up with a good code book’’ until we became thoroughly familiar with
its precepts.
Codes are particu
DUE-60WKS-CE240/22PO 模块用于控制传输速度 Kollmorgen
