RFQ 準備用 PDF ワークシート
見積前の情報整理や、営業から顧客へ転送する用途に使える英語 PDF です。
これらの PDF は RFQ 準備用です。最終的な材料、形状、積層、疲労、取付条件は FeTech の技術レビューが必要です。
Why standard tightening alone is often not enough
In high-temperature or cycling service, a valve does not stay in the condition it had after tightening. Packing settles, bolt stress redistributes, metal expands and contracts, and vibration gradually consumes the load that was available at installation.
Without elastic reserve in the bolting system, the gland can lose sealing stress long before the planned maintenance date.
How disc spring live loading works
Disc springs are installed under the gland bolting or in a dedicated load stack. As packing consolidates or temperature changes the joint, the spring stack moves with the assembly instead of leaving the bolt to behave like a fixed-length spacer.
That is why Belleville washer stacks appear in emissions-sensitive valve systems, high-temperature service and valves that are expensive to retighten in the field.
- Compensates for packing consolidation and wear.
- Helps absorb thermal expansion mismatch.
- Maintains a more stable bolt load over time.
- Reduces the frequency of manual retightening in many applications.
Selection points that matter in real valve projects
A live loading stack only works when it fits the permitted gland load window. Too little load does not control leakage. Too much load can damage packing, raise stem friction or shorten service life.
For FeTech, the stack review starts with spring rate, available travel, bolt size, corrosion exposure and installation space instead of nominal washer dimensions alone.
- Required packing stress window.
- Operating temperature and thermal cycling severity.
- Corrosive media and environmental exposure.
- Space available above the gland or bolting location.
Where industrial valve springs are commonly specified
Industrial valve springs and live loading washer stacks are common in refineries, power plants, offshore platforms, LNG service and aggressive chemical process lines. These environments punish bolted joints that depend only on initial torque.
In export B2B projects, live loading is often paired with stainless or nickel alloy materials so the design can handle both load retention and corrosion risk.
Buyer terms that usually signal a real valve problem
Valve disc springs, disc springs for valves and live loading washer requests usually come from teams trying to reduce leakage, emissions, retightening work or actuator instability. Those are application problems, not product-name problems.
A good quotation connects the spring stack to packing stress, available travel, media exposure and the cost of downtime if sealing load falls below the safe window.
よくある質問
What is the difference between live loading washers and ordinary spring washers?
Live loading stacks are engineered as a defined elastic system with known travel and load characteristics. Ordinary spring washers are not a direct substitute when a valve design needs measurable preload retention.
When are nickel alloy disc springs worth the extra cost in valve service?
They become worthwhile when temperature, corrosion, sour service or long maintenance intervals make standard spring steel or common stainless grades too risky for the joint.
FeTech に皿ばね用途の確認を依頼しますか？
図面、積層スペース、目標荷重、温度、媒体、数量を送付してください。材料方向、積層ロジック、見積準備度を確認します。
- DIN 2093 置換または特注形状
- バルブ、フランジ、アクチュエータ、過酷用途の積層
- ステンレス、Inconel、Hastelloy、チタン、耐熱鋼の材料確認
最終形状、疲労寿命、K4 根拠、摩擦、支持面条件は技術確認が必要です。