Anyone who does instrument sizing knows the feeling: a project with hundreds of valves, each requiring Kv calculation,口径 selection, opening verification and accessory configuration. Manual calculation in Excel is error-prone even for copying formulas, let alone that different manufacturers use different catalog formats.
1. Three pain points of manual sizing
The biggest headache is not the single-valve calculation — anyone can do that. The headaches are: consistency — two engineers may get different results for the same valve because density is taken at different temperatures or FL is read from different references.
Manufacturer data formats are inconsistent — one catalog gives Cv, another gives Kv, a third mixes DN and inch units. Every conversion is a chance for error.
Verification steps get skipped — after calculating Kv you should verify opening, check口径 rounding and confirm choked/non-choked flow, but under schedule pressure these steps often get bypassed.
2. Three-step approach to batch sizing
Step one: build a unified data foundation. Standardize all manufacturer product data — valve type,口径 range, Kv tables, actuation method, optional accessories. We have collected data from 60+ manufacturers across 200+ series.
Step two: standardize the calculation engine. Implement liquid, gas and steam formula sets per IEC 60534-2-1 / GB/T 4213-2024, including automatic choked/non-choked flow discrimination, piping geometry correction, opening verification with characteristic curve correction, and口径 rounding rules.
Step three: batch import/export. Import project data tables directly, auto-match manufacturer products, batch-calculate and export the sizing result table.
3. Actual efficiency comparison
Using a real project (200 control valves) as comparison: manual sizing takes about 15 days with 5–10% error rate and poor traceability; tool-assisted sizing takes about 2 hours (including data preparation) with zero errors (automatic verification), full traceability to data sources, and identical results when re-run by a different person.
The greatest value is not 'calculating faster' but 'calculating reliably' — no skipping verification under schedule pressure, no wrong口径 from manual entry errors.
Dacheng's sizing tool supports 60+ manufacturer product data with complete calculation chains for liquid, gas and steam. For batch sizing projects or manufacturer data consolidation, contact through the WeChat mini program 'Wenfa' (search 问阀 in WeChat).
(This article is technical exchange; final selection shall be based on formal service-condition calculation, and technical parameters shall follow the latest product catalog.)
