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ASME B5.49-1998 — Glossary of Power Press Terms
📖 ASME B5.49-1998 is the American National Standard glossary of power press industry terminology, a revision of ANSI/ASME B5.49M-1984. It was developed by Technical Committee 30 (Mechanical Power Presses) of the American Society of Mechanical Engineers Committee on Machine Tools and Components (B5), with roots in the once widely used JIC (Joint Industry Conference) Press Room Standards. The Standard provides a unified, normative set of term definitions for the industries that manufacture or use mechanically and hydraulically powered presses, eliminating ambiguity in industry communication and fostering mutual understanding across design, manufacturing, procurement, operation, and maintenance.
💡 The soul of a glossary is “one concept, one preferred term”: when several words denote the same concept, the Standard gives a full definition only for the preferred term and lists synonymous terms as references to it, building one unified “language” for the whole industry.
1. Purpose, Scope, and Background 📌
In December 1973, the ASME Committee on Machine Tools and Components (B5) reestablished Technical Committee 30 to develop American National Standards addressing the interchangeability of bolsters, press tooling, and mounting provisions among general-purpose presses of comparable bed size, capacity, and type. The committee’s work was based on the JIC Press Room Standards — once the most widely used — and on basic data submitted by U.S. manufacturers of mechanical presses. Its first order of business was a glossary of industry terms: a “Glossary of Mechanical Press Terms” draft appeared in July 1977, and the 1998 edition continues and revises that system to cover both mechanical and hydraulic presses.
The scope of the Standard states that it provides a glossary of terms commonly used in the industries that manufacture or use mechanically and hydraulically powered presses. The terms span press structure, drives, controls, die mounting, safety devices, and auxiliary equipment.
⚠️ Usage note: the Standard follows the “define only the preferred term” rule — if two or more terms denote the same concept, only the preferred term is defined and synonymous terms are listed with a reference to it. Related terms are provided where applicable, following the definition, for easy tracing.
2. Term Organization and Representative Terms 🔧
The “Definitions” section of the Standard is alphabetically organized, with a concise normative definition for each term. The table below extracts a few representative terms by category (meanings summarized):
| Term | Category | Definition Summary |
|---|---|---|
| Bed | Structure | Basis surface of the press that supports the lower die shoe. |
| Slide | Structure | The member that reciprocates vertically on the guides, carries the upper die, and transmits force. |
| Stroke | Motion | The movement of the slide from one limiting position to the other, or the distance of that movement. |
| Adjustable Stroke | Motion | The capability of varying the length of the stroke of a slide. |
| Die Cushion (Air Cushion) | Auxiliary | A pneumatic/hydraulic device in the bed providing blank-holding or ejection force. |
| Automatic Die Change (ADC) | Control | A fully programmable procedure for changing dies without manual intervention. |
| Antirepeat | Safety control | A function limiting the press to a single cycle even while the actuating control is held operated. |
| Two-Hand Control | Safety device | A control requiring both hands to be used, keeping the hands clear of the danger zone. |
| Barrier Guard | Safety device | A guard fencing the danger zone around slide and die. |
| Pneumatic Power Press | Drive type | A press driven by compressed air (synonyms reference this preferred term). |
The table above is only a summary; the Standard defines many more entries — from “actuating control,” “adapter plate,” and “bed press” to “die clamping” and beyond — covering hundreds of items alphabetically. Many definitions also carry closely related terms, so a reader who looks up a single word can quickly navigate the whole concept family: for example, looking up “slide” leads to stroke, shut height, adjustment, and clutch/brake terminology, and each of those links onward in turn.
Press terminology is genuinely difficult for newcomers because the same machine part is called by different names in different shops and in different countries. “Ram” and “slide,” “bolster” and “bed,” “die” and “tooling,” “tonnage” and “capacity” — each pair is the same object seen from different traditions. The Standard cuts through this by designating one preferred term per concept and restricting definitions to those preferred terms, which is why it remains useful long after the specific press models it describes have changed.
🚨 Why terminology matters: in purchase contracts, safety assessments, and operating documents, misusing terms such as “antirepeat,” “two-hand control,” and “barrier guard” can leave safety requirements unmet. Contracts and technical documents should strictly use the Standard’s preferred terms.
3. Using the Glossary 🛠️
- 🔍 Prefer the preferred term: use the Standard’s preferred terms in specifications, manuals, and safety documents; when a synonym first appears, parenthesize its official name.
- 🔧 Follow related terms: use the related-term references at each definition to trace the full concept cluster instead of reading items in isolation.
- 📊 Cross-department consistency: letting design, purchasing, quality, and safety use the same glossary significantly reduces rework and disputes caused by “different names for the same thing.”
- 📋 Training material: adopt the glossary as a base text for operator and maintenance training so that concepts like stroke, tonnage, slide, and die shut height are understood consistently.
4. Frequently Asked Questions ❓
❓ Q: Does B5.49 apply only to mechanical presses?
A: No. The scope explicitly covers terms for industries that manufacture or use both mechanically and hydraulically powered presses; terms specific to one drive type naturally appear as well. Use the Standard as the authority.
A: No. The scope explicitly covers terms for industries that manufacture or use both mechanically and hydraulically powered presses; terms specific to one drive type naturally appear as well. Use the Standard as the authority.
❓ Q: Why aren’t synonymous terms each given their own definition?
A: To eliminate ambiguity and ensure consistency — if two names each had their own definition, the definitions could disagree. The Standard defines only the preferred term and references synonyms to it, guaranteeing “one concept, one definition.”
A: To eliminate ambiguity and ensure consistency — if two names each had their own definition, the definitions could disagree. The Standard defines only the preferred term and references synonyms to it, guaranteeing “one concept, one definition.”
❓ Q: How do I look up a term?
A: Entries are alphabetical, so search directly by letter; if you only recall a synonym, its entry will reference the preferred term’s definition.
A: Entries are alphabetical, so search directly by letter; if you only recall a synonym, its entry will reference the preferred term’s definition.
❓ Q: Are safety terms like antirepeat and two-hand control mandatory requirements?
A: B5.49 is a glossary and does not itself impose safety requirements; however, precise terminology is a prerequisite for correctly applying safety standards such as the ANSI B11 press-safety series. Use these standard terms accurately in safety documents.
A: B5.49 is a glossary and does not itself impose safety requirements; however, precise terminology is a prerequisite for correctly applying safety standards such as the ANSI B11 press-safety series. Use these standard terms accurately in safety documents.
