HIWIN WEH-CA Wide Rail Linear Guideway Block and Rail

The HIWIN WEH-CA is the square block of the WE series, a four-row wide rail ball linear guideway for single-rail axes and compact designs. The wide rail gives high moment rigidity with a low centre of gravity, so one rail can often replace the usual pair where space is limited or the load is carried off-centre.

A wide rail guideway for single-rail and low-profile axes

According to the catalog, the WE series has equal load ratings in the radial, reverse radial and lateral directions, with contact points at 45 degrees. The wide rail, together with this arrangement, gives high rated loads, moments and rigidity, and the self-aligning behaviour absorbs most installation error while still meeting high accuracy standards.

HIWIN names single-axis robots and single-axis equipment with high anti-rolling requirements, as well as automation devices, semiconductor equipment and blow moulding machines, among the main applications. The square block comes in sizes 17 to 50, and the flange WEW-CC block gives a wide mounting face for loads that tilt the carriage.

Technical specifications

Size range and load ratings

Square WEH-CA blocks are listed first; the flange WEW-CC blocks share the same ratings and differ in width and mounting. H is the assembled height, W the block width, L the block length, then C and C0 and the block and rail mass.

Flange WEW-CC blocks: WEW17CC W 60 mm, 0.13 kg; WEW21CC W 68 mm, 0.23 kg; WEW27CC W 80 mm, 0.43 kg; WEW35CC W 120 mm, 1.26 kg; WEW50CC W 162 mm, 3.71 kg.

Ordering code, preload and selection

A WE model number gives the series, block type (W flange or H square), size, load type, block mounting, blocks per rail, rail mounting, rail length, accuracy, preload, rails per axis and dust protection. Interchangeable blocks and rails are offered in C, H and P accuracy with Z0 or ZA preload; the non-interchangeable type adds ZB and the SP and UP accuracies.

Choose Z0 for a constant load direction and low precision, ZA for low load with high precision, and ZB where rigidity under vibration and shock is needed. The catalog asks for the grease to be checked every 100 km or every 3 to 6 months. Before ordering, confirm the size, block type, preload, accuracy, rail length and end distances, and give the label data of the part you replace. When one wide rail replaces a pair, check the moment loads against the catalog ratings.

Key features of the WEH-CA square block

• Wide rail, low profile: the broad rail spreads the load across a wider base, so the axis resists rolling moments well while the assembled height stays low.
• Four rows at 45° contact: equal ratings in radial, reverse radial and lateral directions mean the block behaves predictably whichever way the load acts.
• Self-aligning behaviour: small mounting errors are absorbed, which helps on frames that are machined but not ground.
• Square body, top mounting: the -CA block bolts from the top into a compact carriage, leaving the flange WEW-CC version for designs that need a wider mounting face.
• Sealing options: standard end and bottom seals can be upgraded with ZZ, KK, DD or the RC reinforced cap where contamination is heavy.

Selecting a size for a single-rail axis

Start from the load case rather than the rail width. Work out the largest radial, lateral and moment loads at the block, including acceleration forces on the moving mass, and compare them with the static rating C0 using a safety factor suited to the duty: higher factors apply where shock, vibration or overhung loads occur. Then estimate the rated life from the dynamic rating C and the expected travel per year. Where one wide rail replaces a pair of narrow rails, the rolling moment is usually the deciding value, so check it against the catalog moment ratings for the block length you select. Remember that preload adds an internal load that reduces life slightly while improving rigidity.

Installation guidance

• Clean the mounting surfaces and reference edges and remove burrs before placing the rail.
• Push the rail against its reference shoulder and tighten the rail bolts in sequence to the torque the catalog gives for the bolt size and material.
• Do not remove the block from the rail without the dummy rail supplied for that purpose, otherwise the balls can fall out.
• Fit end caps over the rail bolt holes when the axis is exposed to chips or dust, so debris does not collect in the counterbores.
• Lubricate before first running and follow the catalog check interval for grease.

Applications in Oman and GCC conditions

In packaging lines, single-axis robots, cutting tables and automated test rigs across Oman, the main enemies of linear guides are fine sand, high ambient temperature and humidity near the coast. Choose the double-lip or scraper seal options and enclose the axis with bellows or covers where airborne dust is present. Heat thins grease, so shorter relubrication intervals are sensible in summer, and a stored spare block should be kept on its dummy rail in a sealed bag with corrosion protection.

What to include in your RFQ

• Full WE model number, or the size, block type, preload and accuracy class.
• Number of blocks per rail and rails per axis.
• Rail length and the end distances at each end.
• Dust protection option and any lubrication accessory.
• Quantity and delivery location.

Documents and quotation

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