HIWIN CGH-CA Linear Guideway with Cover Strip Rail

The HIWIN CGH-CA is the square, heavy load block of the CG series, a four-row ball guideway arranged in the O (back-to-back) configuration for high rolling-moment resistance. It has an integrated recirculation path, a metal scraper as standard and an optional stainless cover strip over the rail mounting holes, so it suits machine tools that produce hot chips and fine particles.

An O-arrangement guideway for large rolling moments

The catalog describes CG as a four-row arc-tooth contact guideway with high rigidity, high load and high torsional resistance, loaded equally in four directions. Its O (DB) arrangement has a longer moment range than the X (DF) arrangement and suits applications with a larger rolling moment. In HIWIN’s rigidity test the CG25C-ZA shows torsional rigidity more than 100 percent higher than the HG25C-ZA.

Other features are the better smoothness of the integrated recirculation component, a metal scraper that protects against hot chips and particles, a special stainless cover strip as a dust-protection alternative to bolt caps, and a lubrication design for short-stroke motion. HIWIN lists machine centres, NC lathes, grinding machines, precision machining and heavy cutting machines for the CGH block.

Technical specifications

Size range and load ratings of the CGH block

H is the assembled height, W the block width, L the block length, then C and C0 and the block and rail mass. The CGL low square and CGW flange blocks are in the catalog extract.

Ordering code, preload and selection

The code CGH25CAE2R1600EZAPII+DD+CS shows the fields: series, block type, size, load type, block mounting (A top, C top or bottom), blocks per rail, rail mounting, rail length, accuracy, preload, rails per axis and dust protection, here with double seals and a cover strip. The interchangeable type reaches up to P class accuracy and can be exchanged freely between blocks and rails.

Pick ZA for machining centres and precision tables, Z0 for light transport axes and ZB for heavy cutting with shock loads. Check the replenishment interval in the catalog: 3000 km for light loads, shorter when the load ratio is higher. Before ordering, confirm the size, block type, preload, accuracy, cover strip requirement, rail length and E values, and send the label data of the guideway you replace.

Selection considerations for the CGH-CA block

The first decision is the size, which follows from the loads and moments acting on each block and the required service life. Work out the forces from the machine weight, cutting or process forces and acceleration, distribute them over the blocks, and compare the result with the dynamic and static load ratings in the table with a safety margin suited to the duty. Where the axis carries an overhanging load or tool, the rolling-moment resistance of the O arrangement is the main reason for choosing the CG series, so check the moment case as well as the direct load.

Then choose the load type, accuracy class and preload to match the machine. A heavier preload increases rigidity but also the running resistance and the demands on mounting surface accuracy, so it should be balanced against the drive and the application. Decide early whether the cover strip, double seals or other dust protection is needed, because these are part of the ordering code.

Installation practice

Guideway accuracy depends on the mounting surfaces. Machine the reference faces flat and square, clean them carefully, and remove burrs before the rail is placed. Press the rail against its reference edge, tighten the mounting screws in sequence from one end, and follow the tightening values in the HIWIN catalog. Mount the blocks without hammering on them, keep the block and rail together as supplied when the set is not interchangeable, and check that the table runs smoothly over the full stroke before the drive is connected. Fit the cover strip after the rail screws are tightened, following the catalog instructions.

Lubrication and maintenance

Correct lubrication keeps rolling friction low and protects the raceways. Fill the blocks before running, then follow the replenishment interval from the catalog and shorten it for short-stroke motion, high loads or dirty environments. Inspect the scrapers and seals at each service, clean chips and dust from the rail top, and listen for changes in running noise, which often show contamination or lack of lubricant before damage occurs.

Linear guideways in GCC workshops

Machine shops and fabrication plants in Oman and the GCC face fine sand dust, high temperatures and humid coastal air. Dust is abrasive in the ball tracks, so effective scrapers, seals and the cover strip over the rail holes are worth specifying, and the machine enclosure should be kept closed. Store rails and blocks in their packaging in a dry place until installation, and protect exposed steel surfaces against corrosion. For an RFQ, state the full ordering code if known, or the size, block type, load type, rail length, accuracy, preload, dust protection, number of blocks and rails, and the quantity.

Documents and quotation

The linked PDF is the CG chapter of the HIWIN Linear Guideway Catalog G99TE24-2410, unchanged. More items are in our product range. Seven Star LLC is an independent supplier in Muscat; send the CG model number, rail length, quantity and delivery location with your RFQ.