MGF GSSW-02.1A Standard Duty 4-Leg Chain Instruction Manual
- October 30, 2023
- MGF
Table of Contents
GSSW-02.1A Standard Duty 4-Leg Chain Instruction Manual
GSSW-02.1A Standard Duty 4-Leg Chain
MGF Trench Boxes are simple assembly, robust, two sided excavation support systems, install with an excavator utilising the dig and push or excavate and lower in place techniques. This guide will detail a dig and push installation sequence.
Assembly of a box commences by lowering the first panel flat onto timber skids, using the provided MGF 4-leg chains.
Adjust the telescopic struts to the required length by sleeving the inner within the outer and securing them together using a pin and r-clip. Keep hands/fingers away from connection and pinch points.
Lower the struts into the panel pockets and secure using pins and r-clips. Pins should be inserted from outside the panel.
Lower the second panel onto the struts using an MGF 4 leg chain. Carefully align the panel pockets with the strut ends. Lock into position with pins and r-clips. Once secure, release the 4-leg chain.
Lift the assembled box into a vertical position by using the MGF chain.
Installation normally commences by excavating to a maximum of 1m below ground level (if site conditions permit).
Lower the box into the excavation using an MGF 4 leg chain. Release the chains. An operative on even ground should remove chains only if the box upstand is 1m above ground level.
Carefully dig and push each panel down using the excavator bucket on the corners of each panel. Push the box downwards in no more than 300mm increments. Excavating ahead of the panel cutting edges as required. Take care to avoid damage.
Carefully dig and push each panel down using the excavator bucket on the
corners of each panel. Push the box downwards in no more than 300mm
increments. Excavating ahead of the panel cutting edges as required. Take care
to avoid damage.
Once the base unit is at a sufficient depth a top unit can be added. Lower the
top onto base and connect together to form a single box ensuring all 4 top to
base connection points are fully secured.
The
pins are inserted from the outside and r-clips are fitted from the inside.
Always ensure a safe secure means of access is provided prior to entry.
Dig and push the assembled box to the required depth.
If an additional top is required repeat steps J to K.
On reaching the final depth secure the box by backfilling against the panels and if required batter back the open ends of the excavation. End safe panels or trench sheets can be used to secure the ends.
Shoring Safety Products can now be installed.
Subject to a final inspection the excavation is now safe to enter.
Note: Make sure the panels are installed plumb, square and level to each
other.
Extraction of the boxes normally commences by backfilling around the
installed structure. Any shoring safety products attached to the boxes should
now be removed.
Attach an extraction chain in turn, to each top extraction point.
Slowly apply an upward force to break any adhesion that may have occurred
between the panel and the ground.
Progressively backfill the excavation as
the box is removed.
Once the top unit is clear of the ground connect an MGF 4 leg chain
and remove the 4 pins at the connection points, before lifting the top clear
of the excavation.
Repeat the extraction process for the
base unit until the base can be removed. Backfill and compact the ground.
See MGF channel for installation guidance: https://www.youtube.com/user/MGFLtd
Only use chains supplied by MGF for handling, installing and removing MGF box
systems.
UNCONTROLLED WHEN PRINTED
go to www.mgf.co.ukfor latest version
GENERAL Current health and safety legislation requires that construction
equipment users formulate a site specific Safe System of Work (SSoW) to
undertake the works they are proposing This document is intended to provide
sufficient producl specific guidance on handling, installing. maintaining and
removing MGF equipment to allow the SSoW to be compiled It should always be
read in conjunction with the product specific technical tiles and the site
specific design information (including any residual risks to be managed on
site) provided by MGF or others. Users of this equipment should be both
familiar with and competent in its use. MGF can provide toolbox talks and
training material / advice on request. MGF excavation systems can be supplied
with a full range of site safety products and ancillaries. These products are
designed to comply with current best practice and meet the requirements of the
Lifting Operations & Lifting Equipment Regulations. Work at Height Regulations
and the Confined Spaces Regulations. For MGF contact details or further
information visit. www.mgf.co.uk
SAFETY TIPS
- If used in very weak, problematic or saturated ground always ensure a site specific temporary works design is provided.
- Always inspect lifting points prior to every lifting operation and ensure all personnel are well clear of operation.
- Flying of the box above the base of the excavation is not recommended.
- Only access the box via a suitable secured ladder placed within the box. Never enter via the ends/faces of an unsupported excavation.
- Always ensure all pins and retaining clips are correctly fitted prior to use.
- If box becomes stuck in the ground only use designated extraction chains to release each corner at a time. N.B. Extraction loads of up to 50t can be generated.
- Do not allow personnel to enter the box whilst excavator is moving box.
- Always ensure the box is evenly supported by the ground on opposite faces to avoid boxes becoming unstable.
- Always work from a position of safety. Avoid working above on an unsupported edge, an unprotected edge or under a suspended load.
- Very heavy equipment to be installed by competent groundwork contractors only.
- Take care to avoid accidently striking struts or using struts for lifting/moving the box.
- Avoid standing on steel panels especially when wet.
- Do not assemble panels on top of other panels or on sloping ground as they can potentially slide when attaching the top panel.
- Warning! Assembled boxes do not have fully rigid connections and panels can tilt or rotate during assembly or handling. Do not rest ladders against panels.
- Keep hands and fingers away from pinch points when making connections.
- Prior to permitting entry always ensure; panels are installed plumb, square and level to each other. All components are fitted and show no signs of damage or distress and a safe means of access/egress is provided from within the box.
IF IN DOUBT ASK!
MGF Design Services Ltd
mGF Grant House, to:kelt Road Asher In Maker6eld. Wigan. WN4 I. 01942 402 704
F 01942 402 766 E denegnamgt ltd uk
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Guidance for Safe Systems of Work: Trench Boxes
Drawing No. Rev GSSW/02.1A A4
Date of first issue 06.03.2012