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ASME PALD 12b-1988 — Shop Cranes Safety Standard Addenda (b)
🏗️ ASME/ANSI PALD-12b-1988 is the second addenda to the Shop Cranes volume, ASME/ANSI PALD-12-1986. Approved by ANSI on October 6, 1988 and issued on December 31, 1988, it continues the replacement-page mechanism: revisions are incorporated directly into the affected pages of the 1986 edition, marked with a margin note (b) for this addenda and (a) for changes from the previous addenda. The result is a continuous, auditable revision history that keeps the standard current between full editions.
💡 The addenda mechanism lets the PALD Committee publish revisions on a regular yearly basis in response to public review comments and committee actions. Each addenda keeps the standard in “latest-issued” status without waiting years for a new edition.
1. Background of the Standard 📜
This addenda records, for the first time in full, the origins of the PALD series: in June 1979 the Jack Institute asked the B30 Committee (covering cableways, cranes, derricks, hoists, hooks, jacks, and slings) either to develop an automotive jack standard or to fold the equipment into a revision of B30.1, Jacks. When B30 declined, the Jack Institute petitioned ANSI in July 1979 to form a dedicated committee, requesting ASME as sponsor. ASME’s Policy Board approved sponsorship in September 1979; membership was approved in May 1980; and the inaugural PALD Committee meeting took place in July 1980, where it was decided to structure the standard as separate volumes, each complete for design, marking, identification, testing, operation, inspection, and maintenance. The Shop Cranes volume was approved by ANSI as an American National Standard on October 16, 1986.
2. Principal Changes in This Addenda 🔧
The Summary of Changes of PALD-12b-1988 lists the following modifications:
| Page | Location | Change |
|---|---|---|
| iii | Foreword | Editorially revised in its entirety |
| 1–3 | Introduction | (1) Editorially revised in its entirety; (2) Introduction previously revised in Addenda (a) |
| 5 | Section 2 — Definitions | Definition of proof load revised |
| 7 | 3.1 Operating Controls | Revised |
| 7 | 3.4 Proof Load | Revised |
| 8 | 5.1.2 Travel Limit Test | Revised |
| 9 | 7.1.3 Inspection | (1) Subparagraph (c) redesignated as (d); (2) new subparagraph (c) added |
⚠️ Watch the subparagraph redesignation: in 7.1.3 the former item (c) became (d) and a new item (c) was added. Always cite the edition and addenda level when referencing clauses to avoid pointing at the wrong text.
3. Design and Testing Requirements 🔩
The revised definition of “proof load” is central to judging overload capacity. Under para. 3.4, shop cranes without internal load limiting devices must lift a proof load of 150% of rated capacity through the full range of travel without functional damage; “functional damage” means any permanent deformation of the structure and/or loss of sealing capacity in hydraulic components that prevents the crane from meeting the design qualification testing of this volume. The supporting qualification tests include:
- Proof Load Test (5.1.1): the specified proof load is applied to the hook, lifted, sustained, and lowered through full travel.
- Travel Limit Test (5.1.2): extend the boom to the travel limit with no external load and verify the limiting means prevents further extension.
- Instantaneous Load Loss Test (5.1.3): raise a rated load to the point of maximum momentum and remove it suddenly; the crane must leave the ground no more than 12 in. (300 mm).
- Load Sustaining Test (5.1.4): hold rated load at ~100% of lifting range; descent ≤ 1/8 in. (3 mm) in the first minute and ≤ 3/16 in. (4.8 mm) in 10 minutes.
- Release Test (5.1.6): descent rate no more than 3 in./sec (75 mm/s) to prevent uncontrolled lowering.
🚨 The purpose of the definition revision is to unify test practice: a proof load is a load greater than rated capacity, applied at the lifting points to confirm structural integrity. A shop crane that has not passed the 150% proof load test must not be represented as conforming to PALD-12.
4. Engineering Practice Essentials 🛠️
- 🔍 Version verification: confirm that the copy you use includes replacement pages from addenda (a) and (b), and distinguish revision layers by margin notes.
- 🔧 Control inspection: per revised 3.1, verify visibility and accessibility of controls and that release requires positive operator action to prevent accidental lowering.
- 📊 Inspection program: implement periodic inspection per revised 7.1.3, especially the newly added item (c), together with 7.1.4 checks on hydraulics, structure, and hook.
- 📋 Training and records: operators must be trained and qualified; retain the base edition and all addenda pages to form a traceable change chain.
💡 This addenda became effective 3 months after issuance, with prospective application only. For equipment already in service, compare old and new requirements and implement improvements by risk priority.
5. Frequently Asked Questions ❓
❓ Q: How do PALD-12b-1988 and PALD-12a-1987 relate?
A: Both are addenda to the 1986 Shop Cranes volume: 12a is the first revision and 12b the second, which builds on and cross-references the earlier one. Together with the later addenda (c), they form the complete 1986-edition revision chain.
A: Both are addenda to the 1986 Shop Cranes volume: 12a is the first revision and 12b the second, which builds on and cross-references the earlier one. Together with the later addenda (c), they form the complete 1986-edition revision chain.
❓ Q: Why revise the “proof load” definition in an addenda?
A: The definition underpins the 150% overload test. Clarifying that a proof load exceeds rated capacity and is applied at lifting points to confirm structural integrity removes ambiguity for manufacturers and inspectors.
A: The definition underpins the 150% overload test. Clarifying that a proof load exceeds rated capacity and is applied at lifting points to confirm structural integrity removes ambiguity for manufacturers and inspectors.
❓ Q: How can I tell whether my copy of PALD-12 includes this revision?
A: Check for margin notes (a) and (b) and verify the pages and locations in the Summary of Changes; the most reliable route is to request the current revision status from the issuing body.
A: Check for margin notes (a) and (b) and verify the pages and locations in the Summary of Changes; the most reliable route is to request the current revision status from the issuing body.
🔍 Q: After 7.1.3 was renumbered, does my reference to item (c) still hold?
A: The former item (c) is now (d), and the new (c) is newly added content. Cite the edition and addenda level explicitly when referencing clauses.
A: The former item (c) is now (d), and the new (c) is newly added content. Cite the edition and addenda level explicitly when referencing clauses.
