Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
ASME PALD 2a-1988 — Transmission Jacks Safety Standard Addenda (a)
📦 ASME/ANSI PALD-2a-1988 is the first Addenda to the ASME/ANSI PALD-2-1987 Transmission Jacks volume. It was approved by ANSI on October 6, 1988, and issued on January 15, 1989. Addenda revise the base edition through replacement pages, with changes marked by the margin note (a); changes already made in the 1987 edition are marked (87). The emphasis of this Addenda is on the proof load definition, design testing paragraphs, and use/maintenance requirements, further improving the operability of the safety requirements for transmission jacks.
💡 Effect of an Addenda: revisions become effective 3 months after the Addenda issue date. Manufacturers, purchasers, and inspectors working with the 1987 edition must adopt this Addenda in parallel to keep products and practices compliant with the current requirements.
1. Summary of Changes 📌
| Page | Location | Change |
|---|---|---|
| iii | Foreword | Editorially revised in its entirety |
| 1–3 | Introduction | (1) Editorially revised in its entirety; (2) previous changes from the 1987 edition indicated by (87) |
| 5 | Section 2 — definition of “proof load” | Revised |
| 9 | Para. 3.1 | Revised |
| 9 | Para. 3.6 | Revised in its entirety |
| 10 | Para. 5.1.2.3 | Revised |
| 10 | Para. 5.1.2.4 | Revised |
| 11 | Para. 7.1.3(c) | Revised |
| 11 | Para. 7.1.5 | Revised |
2. Proof Load and Design Requirements 🔬
The “proof load” definition is the key criterion for design qualification testing; this Addenda revises it so that test load determination and acceptance are more explicit. In the Design section (Section 3), the revisions to paras. 3.1 and 3.6 further refine the design requirements for transmission jacks:
- Lift platform and load restraint: requirements for the platform assembly (including brackets, adapters, and load restraints) are clarified to ensure a contour-matching, secure grip on the transmission assembly.
- Tilt and locking mechanisms: design requirements cover smooth angle adjustment and reliable locking to prevent posture drift during alignment.
- Stability: resistance to tipping under rated and off-center loading is a core part of design verification.
⚠️ The “revised in its entirety” status of para. 3.6 means the Addenda text governs that design requirement. Any drawing, calculation, or test plan that cites PALD-2-1987 must be checked against the Addenda for paragraph numbering and content.
3. Revisions to Design Qualification Testing 📋
Design qualification testing (Section 5) is the critical step for verifying safety performance. The revisions to paras. 5.1.2.3 and 5.1.2.4 directly affect test method and acceptance:
- Refined test conditions: clearer requirements for load application method, load position, and loading rate so results do not depend on operator technique.
- Acceptance: after testing there must be no functional damage — no permanent deformation that causes loss of sealing capability, loss of load, or excursions beyond the qualification limits.
- Records: test results and acceptance records must be retained as evidence of traceability and conformity.
🚨 Qualification testing is not a one-time exercise. Variations in materials, processes, and quality control across a production run can leave individual units short of the qualified design; incoming inspection must still verify nameplate rated capacity and conformity documents.
4. Use, Maintenance, and Inspection Essentials 🛠️
The revisions to paras. 7.1.3(c) and 7.1.5 strengthen in-service requirements:
- 🔍 Pre-use inspection: check hydraulic leaks, locking mechanisms, and restraint condition before each use.
- 🔧 Load securing: the transmission must be fixed to the platform brackets and restraints before any raising or moving.
- 📐 Low center of gravity: position and secure the load at low level, then raise slowly.
- 📋 Periodic inspection: hydraulic oil, seals, and wear of locking and travel mechanisms on a scheduled basis, with records retained.
5. Frequently Asked Questions ❓
❓ Q: How does PALD-2a-1988 relate to the 1987 edition?
A: 2a-1988 is the first Addenda to the 1987 edition. The currently effective text is the 1987 base pages plus this Addenda’s replacement pages; cite the Standard as “including Addenda PALD-2a-1988.”
A: 2a-1988 is the first Addenda to the 1987 edition. The currently effective text is the 1987 base pages plus this Addenda’s replacement pages; cite the Standard as “including Addenda PALD-2a-1988.”
🔍 Q: What do the margin notes (a) and (87) mean?
A: (a) marks changes introduced by this Addenda (the first one); (87) marks content changed in the formal 1987 revision. The different markers let users trace each change to its source.
A: (a) marks changes introduced by this Addenda (the first one); (87) marks content changed in the formal 1987 revision. The different markers let users trace each change to its source.
❓ Q: When do Addenda revisions take effect?
A: Under the PALD series rules, Addenda revisions take effect 3 months after the Addenda issue date. Manufacturers must produce and test to the new requirements thereafter, and users must adopt them in inspection documents.
A: Under the PALD series rules, Addenda revisions take effect 3 months after the Addenda issue date. Manufacturers must produce and test to the new requirements thereafter, and users must adopt them in inspection documents.
❓ Q: What is the difference between proof load and rated capacity?
A: Rated capacity is the maximum load permitted in normal use; proof load is a test load above rated capacity applied during design qualification to demonstrate structural margin. The two must not be confused.
A: Rated capacity is the maximum load permitted in normal use; proof load is a test load above rated capacity applied during design qualification to demonstrate structural margin. The two must not be confused.
