Scaffolding Screw Jack Manufacturer

One‑sentence abstract: Scaffolding screw jack is an adjustable load‑bearing metal component for scaffolding and formwork shoring systems, achieving vertical height calibration and uniform load transfer through threaded structural cooperation.

Product introduction:

Scaffolding screw jack is an independent supporting hardware unit applied to temporary construction support structures, consisting of threaded rod, adjusting nut, base plate or U‑shaped head, each structural part completes its own mechanical function without relying on other scaffolding accessories to realize basic supporting performance. The main raw material is structural carbon steel, and two rod‑body structures are available: solid steel bar and hollow seamless steel pipe. Solid rod bodies are formed by cutting and processing solid round steel, featuring high compression resistance and bending resistance, while hollow rod bodies are made of seamless steel pipe, presenting relatively light overall weight. Threads are mostly formed by cold rolling process, which improves surface hardness of thread teeth and reduces wear risk in repeated rotation. Adjusting nuts can be cast or forged, and the structural difference affects the anti‑shear performance under long‑term load. Base plate is welded to the bottom of rod body, and its enlarged plane increases contact area with ground or bearing surface, dispersing vertical pressure and reducing local subsidence probability on soft foundation.

Surface anti‑corrosion treatment includes hot‑dip galvanizing, electro‑galvanizing and paint coating. Hot‑dip galvanizing forms thick alloy protective layer covering rod body, thread and welding position, adapting to long‑term outdoor exposure and marine transportation environment. Electro‑galvanizing generates thin zinc layer on metal surface, suitable for short‑cycle turnover usage scenarios. Paint‑treated surfaces are prone to coating peeling when threads rotate and components collide, so they are rarely adopted for engineering projects with high turnover frequency. According to installation positions, screw jacks fall into base jack and U‑head jack. Base jack is arranged at the bottom of scaffolding vertical tubes, bearing total vertical load of frames and compensating elevation deviation of foundation surface. U‑head jack is installed at the top of supporting uprights, with U‑shaped groove clamping horizontal steel tubes or wood beams to transfer formwork and concrete gravity load.

Multiple dimensional parameters define mechanical performance of screw jacks. Rod outer diameter covers common specifications such as 30mm, 32mm, 34mm. Larger diameter corresponds to higher ultimate compression capacity. Effective adjustment stroke determines available height adjustment range, and the exposed thread section beyond effective stroke will lower structural rigidity. Base plate has multiple size options, and insufficient plate area will lead to excessive ground pressure. This component matches various scaffolding systems, including tube‑and‑coupler scaffolding, ringlock, cuplock and frame‑type shoring frames, and dimensional tolerance shall conform to corresponding international specification requirements during matching.

Before being put into use, visual inspection and sampling mechanical test are required as independent inspection items. Visual inspection checks rod bending, surface cracks, welding defects, thread tooth damage and anti‑corrosion layer peeling. Recycled screw jacks need more careful screening. Even if surface condition looks intact, metal fatigue may accumulate after multiple load cycles, which cannot be identified only by appearance. Sampling compression test verifies ultimate bearing capacity and anti‑deformation performance. Components with permanent deformation, thread slipping and structural cracks shall be eliminated and cannot be mixed for construction application. Random cutting, welding or hole punching on finished screw jacks is prohibited, as secondary processing will change original section characteristics and weaken load‑bearing performance.

Scaffolding screw jacks are designed for cyclic turnover. After dismantling of scaffolding and formwork, concrete mortar, dust and attachments on rod body and threads need to be thoroughly cleared. Residues staying in thread gaps will cause nut jamming and influence height adjustment and locking effect in subsequent deployment. Components shall be stored in dry and ventilated environment, classified by type and specification, avoiding long‑term soaking in rainwater and damp soil. In practical construction, excessive extension of threaded rod, placement on uneven ground and over‑limit load are all improper operation modes, which may induce local deformation of components. As a standalone supporting unit, its structural condition directly influences local stress state of temporary support frames, and its dimensional consistency and mechanical stability constitute important prerequisites for safe operation of scaffolding and formwork shoring systems.