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ASME B107.23-2004 — Pliers: Multiple Position, Adjustable
🔧 ASME B107.23-2004 is the dedicated American National Standard for multiple position, adjustable pliers, replacing ASME B107.23M-1997. Commonly known in the trade as “water pump pliers,” these tools use a sliding joint or a multi-slot tongue-and-groove adjustment mechanism to vary the jaw opening continuously or in discrete steps over a wide range, making them indispensable for pipe installation, general mechanical repair, and automotive work where a variety of round or flat workpieces must be gripped. The Standard was developed by the ASME B107 Hand Tools and Accessories Standards Committee and approved by the American National Standards Institute (ANSI) as an American National Standard on February 19, 2004.
💡 After the B107 committee expanded its scope to include safety considerations in 1996, its plier standards adopted a common three-pillar structure — general and dimensional data, safety considerations, and test methods. B107.23-2004 is a typical product of that approach.
1. Scope and Classification 📌
This Standard defines the general and dimensional data and safety considerations specifically applicable to multiple position pliers, and specifies the test methods used to evaluate performance against the defined requirements. Products are classified into two types by joint construction and jaw form:
- Type I — Adjustable Joint: angle-nose designs with multiple-groove tongues. Class 1 includes Style A (straight, serrated jaws), Style B (curved, serrated jaws), Style C (parrot-nosed jaws), and Style D (straight, smooth jaws); Class 2 is the multiple-holes adjustment design.
- Type II — Slip Joint: combination jaws. Class 1 covers Style A (straight nose, regular) and Style B (straight nose, thin); Class 2 is the bent-nose design.
As in other B107 standards, the inclusion of dimensional data does not imply that all products described are stock production sizes — purchasers should consult manufacturers for lists of stock sizes.
⚠️ B107.23 covers multiple-position adjustable pliers only. Fixed pivot slip joint pliers and locking pliers are governed by B107.22M and B107.24 respectively. Always state the full Type/Class/Style designation in specifications and purchase orders to avoid confusion.
2. Dimensional and Technical Requirements 📏
The Standard provides complete dimensional tables (Tables 1 through 6) for every Type/Class/Style, covering overall length, jaw opening range, jaw length, tongue dimensions, and adjustment-slot positions, supported by figures (Figures 1 through 8) that illustrate the construction of each form. Dimensional tolerances ensure interchangeability and consistent function. The Standard also requires that pliers be proportioned in all parts so as to meet strength, durability, and ease-of-operation requirements.
| Designation | Construction Features | Typical Uses |
|---|---|---|
| Type I, Class 1, Style A | Adjustable joint, angle nose, multi-groove tongue, straight serrated jaws | General gripping and wrenching with slip-resistant contact |
| Type I, Class 1, Style B | Adjustable joint, angle nose, multi-groove tongue, curved serrated jaws | Gripping pipes, fittings, and curved surfaces |
| Type I, Class 1, Style C | Adjustable joint, parrot-nosed jaws | Gripping thin-walled or irregular workpieces |
| Type I, Class 1, Style D | Adjustable joint, straight smooth jaws | Gripping workpieces that must not be marred |
| Type I, Class 2 | Adjustable joint, multiple holes | Rapid multi-position adjustment with large opening |
| Type II, Class 1, Styles A/B | Slip joint, combination jaws, straight nose (regular/thin) | Light-to-medium gripping, cutting, and crimping assist |
| Type II, Class 2 | Slip joint, combination jaws, bent nose | Gripping and wrenching in confined spaces |
3. Material, Hardness, and Surface Quality 🛡️
Materials used in manufacturing must produce pliers that conform to all requirements of this Standard, with all parts proportioned for adequate strength, durability, and ease of operation. Handles are typically required to be through-hardened to 30 to 50 HRC, or case-hardened to a surface hardness of 75 to 86 HR15N with a case depth of at least 0.010 in (0.25 mm), combining bending strength with wear resistance. The jaw working areas must have appropriate hardness and gripping performance. All exterior surfaces must be free from pits, nodules, burrs, and cracks and receive a rust-preventive treatment; coatings must be adherent and uniform.
🚨 The adjustment mechanism (tongue, slot, or rack) is the most heavily loaded and wear-prone part of an adjustable plier. If the tool jumps out of adjustment, slips teeth, or the jaws close unexpectedly during use, the mechanism is worn or the lock has failed — stop using it immediately to prevent the workpiece from being dropped or the user being injured.
4. Test Procedures 📊
Section 6 of the Standard specifies the test procedures, including the handle load test (evaluating handle strength and permanent set), the jaw grip test, and checks of the opening-adjustment function. Table 7 (Test Parameters) lists the test parameters for each form, and Table 8 (Steel Wire Sizes for Wire Cut Test) gives the wire sizes used to verify the cutting capability of jaws that include a cutter. Test specimens must withstand the applicable procedures without cracking or breaking.
| Test Item | Procedure Focus | Acceptance Criterion |
|---|---|---|
| Handle load test | Apply initial and major loads per Table 7 | Permanent set within the allowed limit |
| Jaw grip test | Grip standard specimens within rated opening | Secure grip without slipping |
| Wire cut test | Shear wire of Table 8 sizes | Clean cut, no significant edge damage |
| Adjustment function check | Cycle through all adjustment positions | Accurate indexing, no jump-out |
5. Engineering Practice Essentials 🛠️
- 🔍 Selection: choose the Style by workpiece shape (round pipe, flat, irregular) and by whether slip resistance or surface protection matters; pick the overall length and adjustment positions from the maximum gripping size.
- 🔧 Use: pre-set the jaws close to the workpiece size, then grip and fine-adjust; for pipes, keep the jaw axis approximately perpendicular to the pipe axis and load along the handle plane — never pry sideways.
- 📋 Maintenance: clean oil and metal chips from the adjustment slot and sliding surfaces, and apply a light rust-preventive lubricant; inspect jaw wear and serration condition.
- 📊 Procurement: verify marking (manufacturer name or trademark and size designations) and request material and hardness documentation; sample-test to the Standard where needed.
6. Frequently Asked Questions ❓
❓ Q: Is “water pump pliers” the same thing as multiple position pliers?
A: In common trade language, yes — “water pump pliers” generally refer to this adjustable-joint, multiple-position tool. For formal procurement, use the standard title “Pliers: Multiple Position, Adjustable” together with the Type/Class/Style designation.
A: In common trade language, yes — “water pump pliers” generally refer to this adjustable-joint, multiple-position tool. For formal procurement, use the standard title “Pliers: Multiple Position, Adjustable” together with the Type/Class/Style designation.
❓ Q: How do I choose between Type I and Type II?
A: Type I adjustable-joint pliers offer a wide adjustment range and reliable indexing — well suited to pipe and fitting work. Type II slip-joint pliers are more compact, suiting light-to-medium gripping in confined spaces.
A: Type I adjustable-joint pliers offer a wide adjustment range and reliable indexing — well suited to pipe and fitting work. Type II slip-joint pliers are more compact, suiting light-to-medium gripping in confined spaces.
🔍 Q: What are the trade-offs between smooth jaws (Style D) and serrated jaws?
A: Smooth jaws protect the workpiece surface but grip less aggressively; serrated jaws grip firmly but may leave marks. Use smooth jaws where surface finish matters and serrated jaws where slip resistance is critical.
A: Smooth jaws protect the workpiece surface but grip less aggressively; serrated jaws grip firmly but may leave marks. Use smooth jaws where surface finish matters and serrated jaws where slip resistance is critical.
❓ Q: Does the Standard allow adding a cheater bar to increase clamping torque?
A: No. The safety requirements and limitations of use prohibit extending the handles to multiply torque beyond the design load, which can fracture the plier body or the adjustment mechanism.
A: No. The safety requirements and limitations of use prohibit extending the handles to multiply torque beyond the design load, which can fracture the plier body or the adjustment mechanism.
