Scaffolding Accessories Adjustable Screw Base Jack Nut

Product Discription

base jack screw rod made from high strength steel rod structure with casting or forging scaffolding jack nut for scaffolding system as ringlock scaffolding system, cuplock scaffolding system, kwikstage scaffolding system, haki scaffolding system, tube&fitting scaffolding system and others.

The base jack nut must have an easy-grip design (usually with two raised handles/wings) for manual adjustment. At the same time, the clearance between the nut and the screw must meet Tolerance Class 6g/6H accuracy to prevent instability due to wobbling.

Base Jack FAQs

1.Q: Safety precautions for installing a base jack?

A: Level ground: The base plate must be in full contact with a solid surface or a wooden mat must be laid. It must not be suspended in mid-air.
    No excessive length: Do not overtighten the nut to increase height, as this can cause the bolt to bend and become unstable.
    Verticality: The bolt must be aligned with the axis of the upright. The tilt angle deviation should be controlled within 0.5%.
    Lubrication and maintenance: Apply grease to the threaded parts regularly to prevent rust and subsequent inability to adjust.

2.Q: What are the strict prohibitions during base jack installation?

A: Prohibit excessive elongation: Do not exceed the manufacturer's specified maximum adjustment height (generally, the length of the screw remaining inside the tube should not be less than 25% of the total length).
    Prohibit eccentric pressure: Ensure the upright is vertically pressed into the center of the base to avoid horizontal forces that could cause overturning.
    Prohibit unstable support blocks: Wooden blocks or channel steel must be used on soft ground; never place it directly on loose soil.

3.Q: What international standards should base jacks meet?

A: Base jacks manufactured by professional companies should meet the following mainstream international standards:
    EN 74-1 / EN 12811: European standards for performance testing of scaffolding accessories.
    ANSI/SSFI: American Scaffolding and Formwork Association's load testing specifications for adjustable base jacks.
    AS 1576: Australian/New Zealand scaffolding safety standard.

4.Q: What are the requirements for the base jack according to BS 1139?

A: The screw must be made of structural steel conforming to EN 10025 (such as S235 or S355). The base plate must be at least 5mm thick and typically has an area of at least 150mm x 150mm to ensure that the pressure distribution on the concrete or pad conforms to the calculated model.

5.Q: What are the requirements for Base Jack Nuts according to BS 1139 standard?

A: The nut must have an easy-grip design (usually with two raised handles/wings) for manual adjustment. At the same time, the clearance between the nut and the screw must meet Tolerance Class 6g/6H accuracy to prevent instability due to wobbling.