How to write technical specifications for clean air equipment procurement?

When purchasing clean air equipment, technical specifications are the common basis for quotation, delivery and acceptance. If the specifications are written clearly, the cost of follow-up communication will be low and there will be fewer changes; if the specifications are written vaguely, problems such as inconsistent quotations, inconsistent delivery content, and disputes over acceptance conditions may easily occur.

Technical specifications do not simply list a few parameters, but transform project requirements into verifiable terms. The following will start from the use boundary, performance parameters, installation interface, control requirements, acceptance terms and version management.

From project tasks to verifiable parameters

The first step in the specification is to describe the purpose and protection boundaries of the equipment. include:

• What and where the equipment protects;

• Use environment and background conditions;

• The type and particle size of contaminants that need to be controlled;

• Running status and operation mode;

• Special requirements, such as anti-static, corrosion resistance, low vibration, etc.

These contents determine the direction of subsequent parameter selection. If the purpose is unclear, the parameters will have no basis. To determine the protection boundary, please refer to What are the prerequisites for purifying only key workstations? , first clarify the sensitive links and protection scope.

Describe component efficiency, complete machine air volume and site level respectively.

In technical specifications, there is confusion between component efficiency and field grade. The three should be described separately:

• Filter efficiency: described by adopted standards, test particle size and air volume;

• Air volume of the whole machine: described according to the operating point with filter and the static pressure outside the machine;

• Site cleanliness levels: described by region, particle size, status and sampling rules.

You cannot use one 'Level 100' or 'ISO 5' to cover all requirements. For the difference between filter efficiency and field grade, please refer to What is the difference between cleanliness level and filtration efficiency , and the difference between components and complete machine, please refer to Is FFU's nominal air volume tested with a filter?。

Performance parameters should correspond to the operating point

Parameters such as air volume, static pressure, power, noise, etc. should indicate the corresponding test conditions and working points. Only writing the maximum air volume or maximum pressure cannot reflect the actual use capacity.

Specifications should require:

• Filter configuration corresponding to air volume and static pressure;

• Power and noise at operating point;

• Speed ​​regulation range and operating mode;

• The working point of the filter at the initial resistance and final resistance.

For the method of determining the working point, please refer to Why should we look at the complete performance curve when selecting FFU? , the meaning of external static pressure can be referred to What does FFU external static pressure mean?。

Installation interface and site conditions

The specification should clarify the interface conditions between the equipment and the site, including:

• Overall dimensions and installation space;

• Ceiling module or installation basis;

• Air inlet and return air interface;

• power, communication and control interfaces;

• Maintenance access and filter replacement path.

Unclear installation interfaces may make it impossible to install or maintain the equipment after it arrives at the site. To determine ceiling matching, please refer to How does the FFU appearance size match the ceiling module? , for maintenance space considerations, please refer to What later expenses will be increased due to insufficient maintenance channels?。

Control and linkage requirements

The equipment control method and linkage logic should be specified in the specification:

• Independent control or centralized control;

• Speed ​​regulation method and operation mode;

• Linkage interface with equipment or production lines;

• Condition monitoring and alarm requirements;

• How to handle abnormal conditions.

For partition management of multiple devices, please refer to FFU group control system , understand the choice of control method.

Acceptance Terms and Delivery Documents

The specification should specify the acceptance conditions, including:

• Factory test projects and field test projects;

• Detect location, particle size and status;

• Judgment criteria;

• Information and records required to be submitted.

Factory testing and field testing have different conditions and cannot be substituted for each other. For relevant differences, please refer to What are the differences between factory testing and on-site acceptance? , for consideration of acceptance preparation, please refer to What preparations need to be completed before clean room acceptance?。

Technical version management

The specification should have a version number, and changes should be recorded. include:

• Initial and revised versions;

• Content and reason for change;

• Change confirmation party;

• Impact on quotations, delivery dates and acceptance.

Version management helps avoid inconsistencies in order, production and acceptance basis. When modularizing expansion, the unification of interfaces and versions is particularly important. Please refer to What are the expansion conditions for using independent modules in clean systems?。

Project judgment example

The specifications of a certain project only stated 'Level 100 FFU' and did not specify the air volume operating point and installation interface. The supplier's quotation varied greatly, and after delivery it was discovered that some equipment did not match the ceiling. Adjustment method: Supplement usage boundaries, working point parameters and installation interface terms, and reunify quotation and delivery requirements.

Another project separately lists filter efficiency, complete machine air volume and site grade requirements in the specification book. Suppliers quoted prices based on the same caliber, and the delivery and acceptance process went smoothly. How to adapt: ​​Use as a template for subsequent projects.

These two situations illustrate that the technical specifications should transform requirements into verifiable terms, and describe performance, interfaces and acceptance respectively.

Key points for selection and acceptance inspection

Aili industrial equipment supporting support

The technical specifications must be clearly written, provided that the supplier can match the configuration of filters, fans, motors, control systems and complete machine assembly. Aili Industrial has collaborative capabilities in all aspects of clean air equipment. It can check performance parameters, installation interfaces, control methods and acceptance data based on project usage, protection boundaries and operating conditions, and help write technical specifications into terms that can be matched for quotation, delivery and acceptance, reducing subsequent changes and caliber differences.