Product Description
Knob Plunger Positioning Bushing Introduction
● Product Introduction
This positioning bushing is precision turned and fully quenched from high-quality carbon steel, designed with a shoulder limiting structure. The outer flange surface is black oxide treated for rust prevention, while the inner bore is precision ground. It is a special wear-resistant bushing matched with pull index plungers and indexing plungers. Installed inside mounting holes of fixture plates and equipment frames, it serves as a guiding support for the reciprocating pin shaft of plungers, bears friction loss instead of base holes, effectively avoiding hole enlargement and deformation caused by long-term friction, and extending the service life of the whole positioning assembly.
● Structural Features
● Integrated Shoulder Positioning Structure
Built-in limiting flange shoulder realizes accurate positioning during installation, firm assembly without slipping or deviation, no extra retaining rings required.
Quenched Carbon Steel with Excellent Wear Resistance
The carbon steel base is integrally heat treated and quenched to achieve high hardness, outstanding anti-friction and anti-extrusion performance. It resists grooving and abrasion under frequent reciprocating sliding of plunger pins for long service life.
High-precision Internal & External Machining
The mirror-finished ground inner bore ensures high dimensional accuracy and smooth sliding for plunger pins without jamming; tight tolerance outer diameter ensures tight press-fit installation without loosening.
Black Oxide Anti-corrosion Treatment
Black oxide finish on the outer flange prevents oxidation and rust, keeping stable structure and appearance under conventional workshop oily and slightly humid environments.
Protection for Base Mounting Holes
Transfers sliding friction to the bushing itself, protecting fixture plates and frame holes from scratching and wear, preventing excessive clearance and positioning accuracy degradation caused by enlarged holes.
● Typical Applications
■ Supporting Use for Knob Index Plungers
Matched with hand knob plungers and indexing plungers inside mounting holes of welding jigs, assembly fixtures and inspection gauges to provide wear-resistant guiding support for plunger pins.
■ Positioning on Automated Production Equipment
Installed in station positioning holes and modular switching holes of assembly lines to prevent abrasion failure of frame holes under frequent plunger extension and retraction.
■ Reinforcement & Refurbishment for Machine Tool Fixtures
Press-fit into worn enlarged holes of old fixtures to restore original positioning accuracy; pre-installed on new fixtures to protect base holes from abrasion fundamentally.
■ Positioning Mechanisms of Heavy-duty Machinery
Guiding support for locating pin holes of construction machinery, limit holes of flip brackets and heavy-load locking pins under intensive reciprocating friction.
■ Locking Structures of Logistic Turnover Toolings
Installed at plunger positioning positions of storage racks and turnover toolings to maintain stable positioning accuracy during repeated locking and unlocking operations.
